Nanomaterials

17 pages, 5048 KiB

Open AccessArticle

Asymmetric Tilt-Induced Quantum Beating of Conductance Oscillation in Magnetically Modulated Dirac Matter Systems

by Nawapan Sukprasert, Patchara Rakrong, Chaiyawan Saipaopan, Wachiraporn Choopan and Watchara Liewrian

Nanomaterials 2024, 14(9), 811; https://doi.org/10.3390/nano14090811 - 6 May 2024

Viewed by 1371

Abstract

Herein, we investigate the effect of tilt mismatch on the quantum oscillations of spin transport properties in two-dimensional asymmetrically tilted Dirac cone systems. This study involves the examination of conductance oscillation in two distinct junction types: transverse- and longitudinal-tilted Dirac cones (TTDCs and [...] Read more.

Herein, we investigate the effect of tilt mismatch on the quantum oscillations of spin transport properties in two-dimensional asymmetrically tilted Dirac cone systems. This study involves the examination of conductance oscillation in two distinct junction types: transverse- and longitudinal-tilted Dirac cones (TTDCs and LTDCs). Our findings reveal an unusual quantum oscillation of spin-polarized conductance within the TTDC system, characterized by two distinct anomaly patterns within a single period, labeled as the linear conductance phase and the oscillatory conductance phase. Interestingly, these phases emerge in association with tilt-induced orbital pseudo-magnetization and exchange interaction. Our study also demonstrates that the structure of the LTDC can modify the frequency of spin conductance oscillation, and the asymmetric effect within this structure results in a quantum beating pattern in oscillatory spin conductance. We note that an enhancement in the asymmetric longitudinal tilt velocity ratio within the structure correspondingly amplifies the beating frequency. Our research potentially contributes valuable insights for detecting the asymmetry of tilted Dirac fermions in type-I Dirac semimetal-based spintronics and quantum devices. Full article

(This article belongs to the Special Issue Emerging Two-Dimensional Semiconductors and Magnetic Materials for Next-Generation Spintronics)

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21 pages, 19406 KiB

Open AccessArticle

A Phosphorylated Dendrimer-Supported Biomass-Derived Magnetic Nanoparticle Adsorbent for Efficient Uranium Removal

by Mingyang Ma, Qunyin Luo, Ruidong Han, Hongyi Wang, Junjie Yang and Chunyuan Liu

Nanomaterials 2024, 14(9), 810; https://doi.org/10.3390/nano14090810 - 6 May 2024

Viewed by 1267

Abstract

A novel biomass-based magnetic nanoparticle (Fe₃O₄-P-CMC/PAMAM) was synthesized by crosslinking carboxymethyl chitosan (CMC) and poly(amidoamine) (PAMAM), followed by phosphorylation with the incorporation of magnetic ferric oxide nanoparticles. The characterization results verified the successful functionalization and structural integrity of the [...] Read more.

A novel biomass-based magnetic nanoparticle (Fe₃O₄-P-CMC/PAMAM) was synthesized by crosslinking carboxymethyl chitosan (CMC) and poly(amidoamine) (PAMAM), followed by phosphorylation with the incorporation of magnetic ferric oxide nanoparticles. The characterization results verified the successful functionalization and structural integrity of the adsorbents with a surface area of ca. 43 m²/g. Batch adsorption experiments revealed that the adsorbent exhibited a maximum adsorption capacity of 1513.47 mg·g⁻¹ for U(VI) at pH 5.5 and 298.15 K, with Fe₃O₄-P-CMC/G1.5-2 showing the highest affinity among the series. The adsorption kinetics adhered to a pseudo-second-order model (R² = 0.99, q_e,exp = 463.81 mg·g⁻¹, k₂ = 2.15×10⁻² g·mg⁻¹·min⁻¹), indicating a chemically driven process. Thermodynamic analysis suggested that the adsorption was endothermic and spontaneous (ΔH° = 14.71 kJ·mol⁻¹, ΔG° = −50.63 kJ·mol⁻¹, 298. 15 K), with increasing adsorption capacity at higher temperatures. The adsorbent demonstrated significant selectivity for U(VI) in the presence of competing cations, with Fe₃O₄-P-CMC/G1.5-2 showing a high selectivity coefficient. The performed desorption and reusability tests indicated that the adsorbent could be effectively regenerated using 1M HCl, maintaining its adsorption capacity after five cycles. XPS analysis highlighted the role of phosphonate and amino groups in the complexation with uranyl ions, and validated the existence of bimodal U4f peaks at 380.1 eV and 390.1 eV belonging to U 4f_7/2 and U 4f_5/2. The results of this study underscore the promise of the developed adsorbent as an effective and selective material for the treatment of uranium-contaminated wastewater. Full article

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16 pages, 9116 KiB

Open AccessEditor’s ChoiceArticle

Interfacing Langmuir–Blodgett and Pickering Emulsions for the Synthesis of 2D Nanostructured Films: Applications in Copper Ion Adsorption

by Andrei Honciuc, Oana-Iuliana Negru and Mirela Honciuc

Nanomaterials 2024, 14(9), 809; https://doi.org/10.3390/nano14090809 - 6 May 2024

Viewed by 1215

Abstract

This research focuses on developing a 2D thin film comprising a monolayer of silica nanoparticles functionalized with polyethyleneimine (PEI), achieved through a novel integration of Langmuir–Blodgett (L-B) and Pickering emulsion techniques. The primary aim was to create a nanostructured film that exhibits dual [...] Read more.

This research focuses on developing a 2D thin film comprising a monolayer of silica nanoparticles functionalized with polyethyleneimine (PEI), achieved through a novel integration of Langmuir–Blodgett (L-B) and Pickering emulsion techniques. The primary aim was to create a nanostructured film that exhibits dual functionality: iridescence and efficient metal ion adsorption, specifically Cu(II) ions. The methodology combined L-B and Pickering emulsion polymerization to assemble and stabilize a nanoparticle monolayer at an oil/water interface, which was then polymerized under UV radiation to form an asymmetrically structured film. The results demonstrate that the film possesses a high adsorption efficiency for Cu(II) ions, with the enhanced mechanical durability provided by a reinforcing layer of polyvinyl alcohol/glycerol. The advantage of combining L-B and Pickering emulsion technology is the ability to generate 2D films from functional nanoparticle monolayers that are sufficiently sturdy to be deployed in applications. The 2D film’s practical applications in environmental remediation were confirmed through its ability to adsorb and recover Cu(II) ions from aqueous solutions effectively. We thus demonstrate the film’s potential as a versatile tool in water treatment applications owing to its combined photonic and adsorptive properties. This work paves the way for future research on the use of nanoengineered films in environmental and possibly photonic applications focusing on enhancing the film’s structural robustness and exploring its broader applicability to other pollutants and metal ions. Full article

(This article belongs to the Special Issue Morphological Design and Synthesis of Nanoparticles (Second Edition))

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13 pages, 9098 KiB

Open AccessArticle

Porous Ruthenium–Tungsten–Zinc Nanocages for Efficient Electrocatalytic Hydrogen Oxidation Reaction in Alkali

by Xiandi Sun, Zhiyuan Cheng, Hang Liu, Siyu Chen and Ya-Rong Zheng

Nanomaterials 2024, 14(9), 808; https://doi.org/10.3390/nano14090808 - 6 May 2024

Viewed by 1147

Abstract

With the rapid development of anion exchange membrane technology and the availability of high-performance non-noble metal cathode catalysts in alkaline media, the commercialization of anion exchange membrane fuel cells has become feasible. Currently, anode materials for alkaline anion-exchange membrane fuel cells still rely [...] Read more.

With the rapid development of anion exchange membrane technology and the availability of high-performance non-noble metal cathode catalysts in alkaline media, the commercialization of anion exchange membrane fuel cells has become feasible. Currently, anode materials for alkaline anion-exchange membrane fuel cells still rely on platinum-based catalysts, posing a challenge to the development of efficient low-Pt or Pt-free catalysts. Low-cost ruthenium-based anodes are being considered as alternatives to platinum. However, they still suffer from stability issues and strong oxophilicity. Here, we employ a metal–organic framework compound as a template to construct three-dimensional porous ruthenium–tungsten–zinc nanocages via solvothermal and high-temperature pyrolysis methods. The experimental results demonstrate that this porous ruthenium–tungsten–zinc nanocage with an electrochemical surface area of 116 m² g⁻¹ exhibits excellent catalytic activity for hydrogen oxidation reaction in alkali, with a kinetic density 1.82 times and a mass activity 8.18 times higher than that of commercial Pt/C, and a good catalytic stability, showing no obvious degradation of the current density after continuous operation for 10,000 s. These findings suggest that the developed catalyst holds promise for use in alkaline anion-exchange membrane fuel cells. Full article

(This article belongs to the Special Issue Advanced Nanostructured Electrode Materials for Energy Storage and Conversion Systems)

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17 pages, 2964 KiB

Open AccessArticle

Assessment of Ingested Micro- and Nanoplastic (MNP)-Mediated Genotoxicity in an In Vitro Model of the Small Intestinal Epithelium (SIE)

by Zhenning Yang, Glen M. DeLoid, Joshua Baw, Helmut Zarbl and Philip Demokritou

Nanomaterials 2024, 14(9), 807; https://doi.org/10.3390/nano14090807 - 6 May 2024

Viewed by 1497

Abstract

Micro- and nanoplastics (MNPs) have become ubiquitous contaminants of water and foods, resulting in high levels of human ingestion exposure. MNPs have been found in human blood and multiple tissues, suggesting that they are readily absorbed by the gastrointestinal tract (GIT) and widely [...] Read more.

Micro- and nanoplastics (MNPs) have become ubiquitous contaminants of water and foods, resulting in high levels of human ingestion exposure. MNPs have been found in human blood and multiple tissues, suggesting that they are readily absorbed by the gastrointestinal tract (GIT) and widely distributed. Growing toxicological evidence suggests that ingested MNPs may pose a serious health threat. The potential genotoxicity of MNPs, however, remains largely unknown. In this study, genotoxicity of primary and environmentally relevant secondary MNPs was assessed in a triculture small intestinal epithelium (SIE) model using the CometChip assay. Aqueous suspensions of 25 and 1000 nm carboxylated polystyrene spheres (PS25C and PS1KC), and incinerated polyethylene (PEI PM_0.1) were subjected to simulated GIT digestion to create physiologically relevant exposures (digestas), which were applied to the SIE model at final MNP concentrations of 1, 5, and 20 μg/mL for 24 or 48 h. PS25C and PS1KC induced DNA damage in a time- and concentration-dependent manner. To our knowledge, this is one of the first assessment of MNP genotoxicity in an integrated in vitro ingestion platform including simulated GIT digestion and a triculture SIE model. These findings suggest that ingestion of high concentrations of carboxylated PS MNPs could have serious genotoxic consequences in the SIE. Full article

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17 pages, 4424 KiB

Open AccessArticle

Boron and Nitrogen Co-Doped Porous Graphene Nanostructures for the Electrochemical Detection of Poisonous Heavy Metal Ions

by Yogesh Chaudhary, Shradha Suman, Benadict Rakesh, Gunendra Prasad Ojha, Uday Deshpande, Bishweshwar Pant and Kamatchi Jothiramalingam Sankaran

Nanomaterials 2024, 14(9), 806; https://doi.org/10.3390/nano14090806 - 6 May 2024

Cited by 3 | Viewed by 1725

Abstract

Heavy metal poisoning has a life-threatening impact on the human body to aquatic ecosystems. This necessitates designing a convenient green methodology for the fabrication of an electrochemical sensor that can detect heavy metal ions efficiently. In this study, boron (B) and nitrogen (N) [...] Read more.

Heavy metal poisoning has a life-threatening impact on the human body to aquatic ecosystems. This necessitates designing a convenient green methodology for the fabrication of an electrochemical sensor that can detect heavy metal ions efficiently. In this study, boron (B) and nitrogen (N) co-doped laser-induced porous graphene (LIG_BN) nanostructured electrodes were fabricated using a direct laser writing technique. The fabricated electrodes were utilised for the individual and simultaneous electrochemical detection of lead (Pb²⁺) and cadmium (Cd²⁺) ions using a square wave voltammetry technique (SWV). The synergistic effect of B and N co-doping results in an improved sensing performance of the electrode with better sensitivity of 0.725 µA/µM for Pb²⁺ and 0.661 µA/µM for Cd²⁺ ions, respectively. Moreover, the sensing electrode shows a low limit of detection of 0.21 µM and 0.25 µM for Pb²⁺ and Cd²⁺ ions, with wide linear ranges from 8.0 to 80 µM for Pb²⁺ and Cd²⁺ ions and high linearity of R² = 0.99 in case of simultaneous detection. This rapid and facile method of fabricating heteroatom-doped porous graphene opens a new avenue in electrochemical sensing studies to detect various hazardous metal ions. Full article

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14 pages, 3470 KiB

Open AccessArticle

A Tape-Wrapping Strategy towards Electrochemical Fabrication of Water-Dispersible Graphene

by Deyue Xiao, Peng He, Haolong Zheng, Shujing Yang, Siwei Yang and Guqiao Ding

Nanomaterials 2024, 14(9), 805; https://doi.org/10.3390/nano14090805 - 6 May 2024

Viewed by 1471

Abstract

Graphene has achieved mass production via various preparative routes and demonstrated its uniqueness in many application fields for its intrinsically high electron mobility and thermal conductivity. However, graphene faces limitations in assembling macroscopic structures because of its hydrophobic property. Therefore, balancing high crystal [...] Read more.

Graphene has achieved mass production via various preparative routes and demonstrated its uniqueness in many application fields for its intrinsically high electron mobility and thermal conductivity. However, graphene faces limitations in assembling macroscopic structures because of its hydrophobic property. Therefore, balancing high crystal quality and good aqueous dispersibility is of great importance in practical applications. Herein, we propose a tape-wrapping strategy to electrochemically fabricate water-dispersible graphene (w-Gr) with both excellent dispersibility (~4.5 mg/mL, stable over 2 months), and well-preserved crystalline structure. A large production rate (4.5 mg/min, six times faster than previous electrochemical methods), high yield (65.4% ≤5 atomic layers) and good processability are demonstrated. A mechanism investigation indicates that the rational design of anode configuration to ensure proper oxidation, deep exfoliation and unobstructed mass transfer is responsible for the high efficiency of this strategy. This simple yet efficient electrochemical method is expected to promote the scalable preparation and applications of graphene. Full article

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18 pages, 5015 KiB

Open AccessArticle

Na₃MnTi(PO₄)₃/C Nanofiber Free-Standing Electrode for Long-Cycling-Life Sodium-Ion Batteries

by Debora Maria Conti, Claudia Urru, Giovanna Bruni, Pietro Galinetto, Benedetta Albini, Vittorio Berbenni, Alessandro Girella and Doretta Capsoni

Nanomaterials 2024, 14(9), 804; https://doi.org/10.3390/nano14090804 - 5 May 2024

Viewed by 1508

Abstract

Self-standing Na₃MnTi(PO₄)₃/carbon nanofiber (CNF) electrodes are successfully synthesized by electrospinning. A pre-synthesized Na₃MnTi(PO₄)₃ is dispersed in a polymeric solution, and the electrospun product is heat-treated at 750 °C in nitrogen flow to [...] Read more.

Self-standing Na₃MnTi(PO₄)₃/carbon nanofiber (CNF) electrodes are successfully synthesized by electrospinning. A pre-synthesized Na₃MnTi(PO₄)₃ is dispersed in a polymeric solution, and the electrospun product is heat-treated at 750 °C in nitrogen flow to obtain active material/CNF electrodes. The active material loading is 10 wt%. SEM, TEM, and EDS analyses demonstrate that the Na₃MnTi(PO₄)₃ particles are homogeneously spread into and within CNFs. The loaded Na₃MnTi(PO₄)₃ displays the NASICON structure; compared to the pre-synthesized material, the higher sintering temperature (750 °C) used to obtain conductive CNFs leads to cell shrinkage along the a axis. The electrochemical performances are appealing compared to a tape-casted electrode appositely prepared. The self-standing electrode displays an initial discharge capacity of 124.38 mAh/g at 0.05C, completely recovered after cycling at an increasing C-rate and a coulombic efficiency ≥98%. The capacity value at 20C is 77.60 mAh/g, and the self-standing electrode exhibits good cycling performance and a capacity retention of 59.6% after 1000 cycles at 1C. Specific capacities of 33.6, 22.6, and 17.3 mAh/g are obtained by further cycling at 5C, 10C, and 20C, and the initial capacity is completely recovered after 1350 cycles. The promising capacity values and cycling performance are due to the easy electrolyte diffusion and contact with the active material, offered by the porous nature of non-woven nanofibers. Full article

(This article belongs to the Special Issue Advances in Nanostructured Electrode Materials: Design and Applications)

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15 pages, 3799 KiB

Open AccessArticle

Optimize Electron Beam Energy toward In Situ Imaging of Thick Frozen Bio-Samples with Nanometer Resolution Using MeV-STEM

by Xi Yang, Liguo Wang, Victor Smaluk and Timur Shaftan

Nanomaterials 2024, 14(9), 803; https://doi.org/10.3390/nano14090803 - 5 May 2024

Cited by 1 | Viewed by 1193

Abstract

To optimize electron energy for in situ imaging of large biological samples up to 10 μm in thickness with nanoscale resolutions, we implemented an analytical model based on elastic and inelastic characteristic angles. This model has been benchmarked by Monte Carlo simulations and [...] Read more.

To optimize electron energy for in situ imaging of large biological samples up to 10 μm in thickness with nanoscale resolutions, we implemented an analytical model based on elastic and inelastic characteristic angles. This model has been benchmarked by Monte Carlo simulations and can be used to predict the transverse beam size broadening as a function of electron energy while the probe beam traverses through the sample. As a result, the optimal choice of the electron beam energy can be realized. In addition, the impact of the dose-limited resolution was analysed. While the sample thickness is less than 10 μm, there exists an optimal electron beam energy below 10 MeV regarding a specific sample thickness. However, for samples thicker than 10 μm, the optimal beam energy is 10 MeV or higher depending on the sample thickness, and the ultimate resolution could become worse with the increase in the sample thickness. Moreover, a MeV-STEM column based on a two-stage lens system can be applied to reduce the beam size from one micron at aperture to one nanometre at the sample with the energy tuning range from 3 to 10 MeV. In conjunction with the state-of-the-art ultralow emittance electron source that we recently implemented, the maximum size of an electron beam when it traverses through an up to 10 μm thick bio-sample can be kept less than

10 n m

. This is a critical step toward the in situ imaging of large, thick biological samples with nanometer resolution. Full article

(This article belongs to the Special Issue The Interaction of Electron Phenomena on the Mesoscopic Scale)

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17 pages, 31276 KiB

Open AccessArticle

Disinfectant-Assisted Preparation of Hierarchical ZSM-5 Zeolite with Excellent Catalytic Stabilities in Propane Aromatization

by Peng Zhang, Jianguo Zhuang, Jisheng Yu, Yingjie Guan, Xuedong Zhu and Fan Yang

Nanomaterials 2024, 14(9), 802; https://doi.org/10.3390/nano14090802 - 5 May 2024

Viewed by 1053

Abstract

A series of quaternary ammonium or phosphonium salts were applied as zeolite growth modifiers in the synthesis of hierarchical ZSM-5 zeolite. The results showed that the use of methyltriphenylphosphonium bromide (MTBBP) could yield nano-sized hierarchical ZSM-5 zeolite with a “rice crust” morphology feature, [...] Read more.

A series of quaternary ammonium or phosphonium salts were applied as zeolite growth modifiers in the synthesis of hierarchical ZSM-5 zeolite. The results showed that the use of methyltriphenylphosphonium bromide (MTBBP) could yield nano-sized hierarchical ZSM-5 zeolite with a “rice crust” morphology feature, which demonstrates a better catalytic performance than other disinfect candidates. It was confirmed that the addition of MTBBP did not cause discernable adverse effects on the microstructures or acidities of ZSM-5, but it led to the creation of abundant meso- to marco- pores as a result of aligned tiny particle aggregations. Moreover, the generation of the special morphology was believed to be a result of the coordination and competition between MTBBP and Na⁺ cations. The as-synthesized hierarchical zeolite was loaded with Zn and utilized in the propane aromatization reaction, which displayed a prolonged lifetime (1430 min vs. 290 min compared with conventional ZSM-5) and an enhanced total turnover number that is four folds of the traditional one, owing to the attenuated hydride transfer reaction and slow coking rate. This work provides a new method to alter the morphological properties of zeolites with low-cost disinfectants, which is of great potential for industrial applications. Full article

(This article belongs to the Special Issue Nanostructured Materials for Carbon Neutrality)

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8 pages, 3815 KiB

Open AccessArticle

Study on Anomalous Hall Effect and Spin–Orbit Torque Effect of TbCo-Based Multilayer Films

by Menglu Yang, Yuanjing Qu, Tao He, Xiong He, Yunli Xu, Lizhi Yi, Liqing Pan and Guangduo Lu

Nanomaterials 2024, 14(9), 801; https://doi.org/10.3390/nano14090801 - 5 May 2024

Viewed by 1215

Abstract

The anomalous Hall effect and spin–orbit torque of TbCo-based multilayer films have been methodically studied in recent years. Many properties of the films can be obtained by the anomalous Hall resistance loops of the samples. We report on the effects of a structure [...] Read more.

The anomalous Hall effect and spin–orbit torque of TbCo-based multilayer films have been methodically studied in recent years. Many properties of the films can be obtained by the anomalous Hall resistance loops of the samples. We report on the effects of a structure composed of two heavy metals as the buffer layers on the anomalous Hall resistance loops of TbCo-based multilayers at different temperatures. The results showed that the coercivity increases dramatically with decreasing temperature, and the samples without perpendicular magnetic anisotropy at room temperature showed perpendicular magnetic anisotropy at low temperatures. We quantified the spin–orbit torque efficiency and Dzyaloshinskii–Moriya interaction effective field size of the films W/Pt/TbCo/Pt at room temperature by measuring the loop shift of anomalous Hall resistance. The results showed that the study of anomalous Hall resistance loops plays an important role in the study of spintronics, which can not only show the basic properties of the sample, but can also obtain other information about the sample through the shift of the loops. Full article

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13 pages, 3239 KiB

Open AccessArticle

Physiochemical and Electrochemical Properties of a Heat-Treated Electrode for All-Iron Redox Flow Batteries

by Nitika Devi, Jay N. Mishra, Prabhakar Singh and Yong-Song Chen

Nanomaterials 2024, 14(9), 800; https://doi.org/10.3390/nano14090800 - 5 May 2024

Viewed by 1553

Abstract

Iron redox flow batteries (IRFBs) are cost-efficient RFBs that have the potential to develop low-cost grid energy storage. Electrode kinetics are pivotal in defining the cycle life and energy efficiency of the battery. In this study, graphite felt (GF) is heat-treated at 400, [...] Read more.

Iron redox flow batteries (IRFBs) are cost-efficient RFBs that have the potential to develop low-cost grid energy storage. Electrode kinetics are pivotal in defining the cycle life and energy efficiency of the battery. In this study, graphite felt (GF) is heat-treated at 400, 500 and 600 °C, and its physicochemical and electrochemical properties are studied using XPS, FESEM, Raman and cyclic voltammetry. Surface morphology and structural changes suggest that GF heat-treated at 500 °C for 6 h exhibits acceptable thermal stability while accessing the benefits of heat treatment. Specific capacitance was calculated for assessing the wettability and electrochemical properties of pristine and treated electrodes. The 600 °C GF has the highest specific capacitance of 34.8 Fg⁻¹ at 100 mV s⁻¹, but the 500 °C GF showed the best battery performance. The good battery performance of the 500 °C GF is attributed to the presence of oxygen functionalities and the absence of thermal degradation during heat treatment. The battery consisting of 500 °C GF electrodes offered the highest voltage efficiency of ~74%, Coulombic efficiency of ~94%, and energy efficiency of ~70% at 20 mA cm⁻². Energy efficiency increased by 7% in a battery consisting of heat-treated GF in comparison to pristine GF. The battery is capable of operating for 100 charge–discharge cycles with an average energy efficiency of ~ 67% for over 100 cycles. Full article

(This article belongs to the Section Energy and Catalysis)

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12 pages, 4388 KiB

Open AccessArticle

Terahertz Biosensor Engineering Based on Quasi-BIC Metasurface with Ultrasensitive Detection

by Jun Peng, Xian Lin, Xiaona Yan, Xin Yan, Xiaofei Hu, Haiyun Yao, Lanju Liang and Guohong Ma

Nanomaterials 2024, 14(9), 799; https://doi.org/10.3390/nano14090799 - 4 May 2024

Cited by 2 | Viewed by 1874

Abstract

Terahertz (THz) sensors have attracted great attention in the biological field due to their nondestructive and contact-free biochemical samples. Recently, the concept of a quasi-bound state in the continuum (QBIC) has gained significant attention in designing biosensors with ultrahigh sensitivity. QBIC-based metasurfaces (MSs) [...] Read more.

Terahertz (THz) sensors have attracted great attention in the biological field due to their nondestructive and contact-free biochemical samples. Recently, the concept of a quasi-bound state in the continuum (QBIC) has gained significant attention in designing biosensors with ultrahigh sensitivity. QBIC-based metasurfaces (MSs) achieve excellent performance in various applications, including sensing, optical switching, and laser, providing a reliable platform for biomaterial sensors with terahertz radiation. In this study, a structure-engineered THz MS consisting of a “double C” array has been designed, in which an asymmetry parameter α is introduced into the structure by changing the length of one subunit; the Q-factor of the QBIC device can be optimized by engineering the asymmetry parameter α. Theoretical calculation with coupling equations can well reproduce the THz transmission spectra of the designed THz QBIC MS obtained from the numerical simulation. Experimentally, we adopt an MS with α = 0.44 for testing arginine molecules. The experimental results show that different concentrations of arginine molecules lead to significant transmission changes near QBIC resonant frequencies, and the amplitude change is shown to be 16 times higher than that of the classical dipole resonance. The direct limit of detection for arginine molecules on the QBIC MS reaches 0.36 ng/mL. This work provides a new way to realize rapid, accurate, and nondestructive sensing of trace molecules and has potential application in biomaterial detection. Full article

(This article belongs to the Special Issue Advances in Plasmonics, Metamaterials, Nanophotonics and Their Applications of Light Modulation and Detection)

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18 pages, 5831 KiB

Open AccessArticle

The Effects of Irradiation on the Improvement in Oxidation Behavior of MX-ODS Steel in Liquid Pb

by Yuwen Xu, Shijing Xie, Jie Qiu, Cunfeng Yao, Wei Yan, Yanfen Li, Chongdou Yang, Shaoqiang Guo, Long Gu and Di Yun

Nanomaterials 2024, 14(9), 798; https://doi.org/10.3390/nano14090798 - 4 May 2024

Viewed by 1063

Abstract

Lead-cooled fast reactors exhibit strong inherent safety performance and good economic features, while material degradation due to corrosion and irradiation is still challenging. Oxide dispersion-strengthened steels are one of the promising candidates for fuel cladding materials. The effects of both irradiation and corrosion [...] Read more.

Lead-cooled fast reactors exhibit strong inherent safety performance and good economic features, while material degradation due to corrosion and irradiation is still challenging. Oxide dispersion-strengthened steels are one of the promising candidates for fuel cladding materials. The effects of both irradiation and corrosion on ODS steel need to be further studied. In this work, MX-ODS steel was irradiated by Fe ions at 500 °C up to 46 dpa. Later, the as-received specimen and the irradiated specimen were used to conduct corrosion tests in oxygen-saturated Pb at 550 °C for 1 h. In the as-received specimen, discontinuous oxides penetrated by Pb and Pb in contact with steel matrix were observed, demonstrating unsatisfactory corrosion resistance of the material. However, in the irradiated specimen after corrosion experiment, a protective oxide layer formed and prevented Pb attack. The oxidation behavior differences between the two specimens can be attributed to the defects produced by irradiation and the structural discrepancy in oxides caused by the formation process. A possible mechanism of irradiation on the corrosion is discussed. In the as-received specimen, Fe atoms loss led to voids in the oxides, and lead penetrated the oxides through these voids. In the irradiated specimen, defects left by previous irradiation helped to form a more uniform oxide layer. The adhesive outer magnetite oxide and the Fe ions generated from where grain boundary oxidation developed retarded the presence of voids and made the oxide layer protective. Full article

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17 pages, 23851 KiB

Open AccessReview

Metal–Organic Framework Nanomaterials as a Medicine for Catalytic Tumor Therapy: Recent Advances

by Jiaojiao Zhang, Meiyu Li, Maosong Liu, Qian Yu, Dengfeng Ge and Jianming Zhang

Nanomaterials 2024, 14(9), 797; https://doi.org/10.3390/nano14090797 - 3 May 2024

Cited by 1 | Viewed by 1750

Abstract

Nanomaterials, with unique physical, chemical, and biocompatible properties, have attracted significant attention as an emerging active platform in cancer diagnosis and treatment. Amongst them, metal–organic framework (MOF) nanostructures are particularly promising as a nanomedicine due to their exceptional surface functionalities, adsorption properties, and [...] Read more.

Nanomaterials, with unique physical, chemical, and biocompatible properties, have attracted significant attention as an emerging active platform in cancer diagnosis and treatment. Amongst them, metal–organic framework (MOF) nanostructures are particularly promising as a nanomedicine due to their exceptional surface functionalities, adsorption properties, and organo-inorganic hybrid characteristics. Furthermore, when bioactive substances are integrated into the structure of MOFs, these materials can be used as anti-tumor agents with superior performance compared to traditional nanomaterials. In this review, we highlight the most recent advances in MOFs-based materials for tumor therapy, including their application in cancer treatment and the underlying mechanisms. Full article

(This article belongs to the Special Issue Advances in Nanomaterials for Energy Conversion and Environmental Catalysis)

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11 pages, 1846 KiB

Open AccessArticle

Redox-Modified Nanostructured Electrochemical Surfaces for Continuous Glucose Monitoring in Complex Biological Fluids

by Sajjad Janfaza, Nandhinee Radha Shanmugam, Pawan Jolly, Prashanthi Kovur, Upasana Singh, Scott Mackay, David Wishart and Donald E. Ingber

Nanomaterials 2024, 14(9), 796; https://doi.org/10.3390/nano14090796 - 3 May 2024

Viewed by 2375

Abstract

Continuous glucose monitoring is valuable for people with diabetes but faces limitations due to enzyme–electrode interactions and biofouling from biological samples that reduce sensor sensitivity and the monitoring performance. We created an enzyme-based electrochemical system with a unique nanocomposite coating that incorporates the [...] Read more.

Continuous glucose monitoring is valuable for people with diabetes but faces limitations due to enzyme–electrode interactions and biofouling from biological samples that reduce sensor sensitivity and the monitoring performance. We created an enzyme-based electrochemical system with a unique nanocomposite coating that incorporates the redox molecule, aminoferrocene (NH₂-Fc). This coating enhances stability via electroactivity and reduces nonspecific binding, as demonstrated through cyclic voltammetry. Our approach enables real-time glucose detection via chronoamperometry with a calculated linear range of 0.5 to 20 mM and a 1 mM detection limit. Validated with plasma and saliva, this platform shows promise for robust metabolite detection in clinical and research contexts. This versatile platform can be applied to accurately monitor a wide range of metabolites in various biological matrices, improving patient outcomes. Full article

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16 pages, 3896 KiB

Open AccessArticle

Super-Suppression of Long-Wavelength Phonons in Constricted Nanoporous Geometries

by P. Alex Greaney, S. Aria Hosseini, Laura de Sousa Oliveira, Alathea Davies and Neophytos Neophytou

Nanomaterials 2024, 14(9), 795; https://doi.org/10.3390/nano14090795 - 3 May 2024

Viewed by 1271

Abstract

In a typical semiconductor material, the majority of the heat is carried by long-wavelength, long-mean-free-path phonons. Nanostructuring strategies to reduce thermal conductivity, a promising direction in the field of thermoelectrics, place scattering centers of size and spatial separation comparable to the mean free [...] Read more.

In a typical semiconductor material, the majority of the heat is carried by long-wavelength, long-mean-free-path phonons. Nanostructuring strategies to reduce thermal conductivity, a promising direction in the field of thermoelectrics, place scattering centers of size and spatial separation comparable to the mean free paths of the dominant phonons to selectively scatter them. The resultant thermal conductivity is in most cases well predicted using Matthiessen’s rule. In general, however, long-wavelength phonons are not as effectively scattered as the rest of the phonon spectrum. In this work, using large-scale molecular-dynamics simulations, non-equilibrium Green’s function simulations, and Monte Carlo simulations, we show that specific nanoporous geometries that create narrow constrictions in the passage of phonons lead to anticorrelated heat currents in the phonon spectrum. This effect results in super-suppression of long-wavelength phonons due to heat trapping and reductions in the thermal conductivity to values well below those predicted by Matthiessen’s rule. Full article

(This article belongs to the Special Issue Nanoscale Heat Transfer Phenomena: Ballisticity, Rectification, Collective Modes, Thermohydrodynamics, Coherence)

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10 pages, 2513 KiB

Open AccessFeature PaperArticle

CdSe/ZnS Quantum Rods (QRs) and Phenyl Boronic Acid BODIPY as Efficient Förster Resonance Energy Transfer (FRET) Donor–Acceptor Pair

by Gianluca Salerno, Pasquale Palladino, Marcello Marelli, Laura Polito, Maria Minunni, Debora Berti, Simona Scarano, Giacomo Biagiotti and Barbara Richichi

Nanomaterials 2024, 14(9), 794; https://doi.org/10.3390/nano14090794 - 3 May 2024

Viewed by 1447

Abstract

The reversibility of the covalent interaction between boronic acids and 1,2- or 1,3-diols has put the spotlight on this reaction for its potential in the development of sensors and for the fishing of bioactive glycoconjugates. In this work, we describe the investigation of [...] Read more.

The reversibility of the covalent interaction between boronic acids and 1,2- or 1,3-diols has put the spotlight on this reaction for its potential in the development of sensors and for the fishing of bioactive glycoconjugates. In this work, we describe the investigation of this reaction for the reversible functionalization of the surface of CdSe/ZnS Quantum Rods (QRs). With this in mind, we have designed a turn-off Förster resonance energy transfer (FRET) system that ensures monitoring the extent of the reaction between the phenyl boronic residue at the meso position of a BODIPY probe and the solvent-exposed 1,2-diols on QRs’ surface. The reversibility of the corresponding boronate ester under oxidant conditions has also been assessed, thus envisioning the potential sensing ability of this system. Full article

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17 pages, 3574 KiB

Open AccessArticle

Electrochemical Sensing Device for Carboplatin Monitoring in Proof-of-Concept Drug Delivery Nanosystems

by Alexandra Pusta, Mihaela Tertis, Catalina Ardusadan, Simona Mirel and Cecilia Cristea

Nanomaterials 2024, 14(9), 793; https://doi.org/10.3390/nano14090793 - 2 May 2024

Cited by 1 | Viewed by 1671

Abstract

(1) Background: Carboplatin (CBP) is a chemotherapeutic drug widely used in the treatment of a variety of cancers. Despite its efficiency, CBP is associated with side effects that greatly limit its clinical use. To mitigate these effects, CBP can be encapsulated in targeted [...] Read more.

(1) Background: Carboplatin (CBP) is a chemotherapeutic drug widely used in the treatment of a variety of cancers. Despite its efficiency, CBP is associated with side effects that greatly limit its clinical use. To mitigate these effects, CBP can be encapsulated in targeted delivery systems, such as liposomes. Ensuring the adequate loading and release of CBP from these carriers requires strict control in pharmaceutical formulation development, demanding modern, rapid, and robust analytical methods. The aim of this study was the development of a sensor for the fast and accurate quantification of CBP and its application on proof-of-concept CBP-loaded nanosomes. (2) Methods: Screen-printed electrodes were obtained in-lab and the electrochemical behavior of CBP was tested on the obtained electrodes. (3) Results: The in-lab screen-printed electrodes demonstrated superior properties compared to commercial ones. The novel sensors demonstrated accurate detection of CBP on a dynamic range from 5 to 500 μg/mL (13.5–1350 μM). The method was successfully applied on CBP loaded and released from nanosomes, with strong correlations with a spectrophotometric method used as control. (4) Conclusions: This study demonstrates the viability of electrochemical techniques as alternative options during the initial phases of pharmaceutical formulation development. Full article

(This article belongs to the Special Issue Trends in Electrochemical Nanosensing)

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14 pages, 5060 KiB

Open AccessArticle

Heat-Annealed Zinc Oxide on Flexible Carbon Nanotube Paper and Exposed to Gradient Light to Enhance Its Photoelectric Response

by Jih-Hsin Liu and Pi-Yu Shen

Nanomaterials 2024, 14(9), 792; https://doi.org/10.3390/nano14090792 - 2 May 2024

Cited by 2 | Viewed by 1516

Abstract

Buckypaper (BP), a flexible and porous material, exhibits photovoltaic properties when exposed to light. In this study, we employed radio frequency (RF) sputtering of zinc oxide (ZnO) followed by rapid thermal annealing to enhance the photovoltaic response of BP. We investigated the impact [...] Read more.

Buckypaper (BP), a flexible and porous material, exhibits photovoltaic properties when exposed to light. In this study, we employed radio frequency (RF) sputtering of zinc oxide (ZnO) followed by rapid thermal annealing to enhance the photovoltaic response of BP. We investigated the impact of various sputtering parameters, such as the gas flow ratio of argon to oxygen and deposition time, on the morphology, composition, resistivity, and photovoltaic characteristics of ZnO-modified BP. Additionally, the photovoltaic performance of the samples under different illumination modes and wavelengths was compared. It was found that optimal sputtering conditions—argon to oxygen flow ratio of 1:2, deposition time of 20 min, and power of 100 watts—resulted in a ZnO film thickness of approximately 45 nanometers. After annealing at 400 °C for 10 min, the ZnO-modified BP demonstrated a significant increase in photocurrent and photovoltage, along with a reduction in resistivity, compared to unmodified BP. Moreover, under gradient illumination, the ZnO-modified BP exhibited a photovoltage enhancement of 14.70-fold and a photocurrent increase of 13.86-fold, compared to uniform illumination. Under blue light, it showed a higher photovoltaic response than under other colors. The enhancement in photovoltaic response is attributed to the formation of a Schottky junction between ZnO and BP, an increased carrier concentration gradient, and an expanded light absorption spectrum. Our results validate that ZnO sputtering followed by annealing is an effective method for modifying BP for photovoltaic applications such as solar cells and photodetectors. Full article

(This article belongs to the Special Issue Growth, Characterization and Applications of Nanotubes (2nd Edition))

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10 pages, 20028 KiB

Open AccessArticle

UV/Ozone-Treated and Sol–Gel-Processed Y₂O₃ Insulators Prepared Using Gelation-Delaying Precursors

by Sangwoo Lee, Yoonjin Cho, Seongwon Heo, Jin-Hyuk Bae, In-Man Kang, Kwangeun Kim, Won-Yong Lee and Jaewon Jang

Nanomaterials 2024, 14(9), 791; https://doi.org/10.3390/nano14090791 - 1 May 2024

Viewed by 1300

Abstract

In this study, a Y₂O₃ insulator was fabricated via the sol–gel process and the effect of precursors and annealing processes on its electrical performance was studied. Yttrium(III) acetate hydrate, yttrium(III) nitrate tetrahydrate, yttrium isopropoxide oxide, and yttrium(III) tris (isopropoxide) were [...] Read more.

In this study, a Y₂O₃ insulator was fabricated via the sol–gel process and the effect of precursors and annealing processes on its electrical performance was studied. Yttrium(III) acetate hydrate, yttrium(III) nitrate tetrahydrate, yttrium isopropoxide oxide, and yttrium(III) tris (isopropoxide) were used as precursors, and UV/ozone treatment and high-temperature annealing were performed to obtain Y₂O₃ films from the precursors. The structure and surface morphologies of the films were characterized via grazing-incidence X-ray diffraction and scanning probe microscopy. Chemical component analysis was performed via X-ray spectroscopy. Electrical insulator characteristics were analyzed based on current density versus electrical field data and frequency-dependent dielectric constants. The Y₂O₃ films fabricated using the acetate precursor and subjected to the UV/ozone treatment showed a uniform and flat surface morphology with the lowest number of oxygen vacancy defects and unwanted byproducts. The corresponding fabricated capacitors showed the lowest current density (J_g) value of 10⁻⁸ A/cm² at 1 MV/cm and a stable dielectric constant in a frequency range of 20 Hz–100 KHz. At 20 Hz, the dielectric constant was 12.28, which decreased to 10.5 at 10⁵ Hz. The results indicate that high-quality, high-k insulators can be fabricated for flexible electronics using suitable precursors and the suggested low-temperature fabrication methods. Full article

(This article belongs to the Special Issue Nano-Structured Thin Films: Growth, Characteristics, and Application)

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10 pages, 2877 KiB

Open AccessArticle

Klein Tunneling in β₁₂ Borophene

by Jinhao Lai, Lekang Wang, Fu Li, Hongbin Zhang and Qingtian Zhang

Nanomaterials 2024, 14(9), 790; https://doi.org/10.3390/nano14090790 - 1 May 2024

Viewed by 1241

Abstract

Motivated by the recent observation of Klein tunneling in 8-Pmmn borophene, we delve into the phenomenon in β₁₂ borophene by employing tight-binding approximation theory to establish a theoretical mode. The tight-binding model is a semi-empirical method for establishing the Hamiltonian based on [...] Read more.

Motivated by the recent observation of Klein tunneling in 8-Pmmn borophene, we delve into the phenomenon in β₁₂ borophene by employing tight-binding approximation theory to establish a theoretical mode. The tight-binding model is a semi-empirical method for establishing the Hamiltonian based on atomic orbitals. A single cell of β₁₂ borophene contains five atoms and multiple central bonds, so it creates the complexity of the tight-binding model Hamiltonian of β₁₂ borophene. We investigate transmission across one potential barrier and two potential barriers by changing the width and height of barriers and the distance between two potential barriers. Regardless of the change in the barrier heights and widths, we find the interface to be perfectly transparent for normal incidence. For other angles of incidence, perfect transmission at certain angles can also be observed. Furthermore, perfect and all-angle transmission across a potential barrier takes place when the incident energy approaches the Dirac point. This is analogous to the “super”, all-angle transmission reported for the dice lattice for Klein tunneling across a potential barrier. These findings highlight the significance of our theoretical model in understanding the complex dynamics of Klein tunneling in borophene structures. Full article

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20 pages, 4960 KiB

Open AccessArticle

Simultaneous Detection of Carbon Quantum Dots as Tracers for Interwell Connectivity Evaluation in a Pattern with Two Injection Wells

by Stephania Rosales, Karol Zapata, Farid B. Cortes, Benjamín Rojano, Carlos Diaz, Carlos Cortes, David Jaramillo, Adriana Vasquez, Diego Ramirez and Camilo A. Franco

Nanomaterials 2024, 14(9), 789; https://doi.org/10.3390/nano14090789 - 1 May 2024

Cited by 4 | Viewed by 1538

Abstract

This study aimed to develop and implement a nanotechnology-based alternative to traditional tracers used in the oil and gas industry for assessing interwell connectivity. A simple and rapid hydrothermal protocol for synthesizing carbon quantum dots (CQDs) using agroindustry waste was implemented. Three commercial [...] Read more.

This study aimed to develop and implement a nanotechnology-based alternative to traditional tracers used in the oil and gas industry for assessing interwell connectivity. A simple and rapid hydrothermal protocol for synthesizing carbon quantum dots (CQDs) using agroindustry waste was implemented. Three commercial CQDs were employed (CQDblue, CQDgreen, and CQDred); the fourth was synthesized from orange peel (CQDop). The CQDs from waste and other commercials with spherical morphology, nanometric sizes less than 11 nm in diameter, and surface roughness less than 3.1 nm were used. These tracers demonstrated high colloidal stability with a negative zeta potential, containing carbonyl-type chemical groups and unsaturations in aromatic structures that influenced their optical behavior. All materials presented high colloidal stability with negative values of charge z potential between −17.8 and −49.1. Additionally, individual quantification of these tracers is feasible even in scenarios where multiple CQDs are present in the effluent with a maximum percentage of interference of 15.5% for CQDop in the presence of the other three nanotracers. The CQDs were injected into the field once the technology was insured under laboratory conditions. Monitoring the effluents allowed the determination of connectivity for five first-line producer wells. This study enables the application of CQDs in the industry, particularly in fields where the arrangement of injector and producer wells is intricate, requiring the use of multiple tracers for a comprehensive description of the system. Full article

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11 pages, 3437 KiB

Open AccessArticle

Hydrogenation of Furfural over Biomass-Based Electron-Deficient Co-NC Nanotube Catalyst

by Zhu Zhu and Guangyue Xu

Nanomaterials 2024, 14(9), 788; https://doi.org/10.3390/nano14090788 - 1 May 2024

Viewed by 1133

Abstract

The conversion of furfural to furfuryl alcohol is one of the most significant reactions from industrial-scale produced biomass platform molecules to value-added chemicals. In this work, biomass-based chitosan was used as both a carbon source and nitrogen source to synthesize nitrogen-doped carbon. With [...] Read more.

The conversion of furfural to furfuryl alcohol is one of the most significant reactions from industrial-scale produced biomass platform molecules to value-added chemicals. In this work, biomass-based chitosan was used as both a carbon source and nitrogen source to synthesize nitrogen-doped carbon. With the addition of cobalt, the optimized 7.5Co-NC-900 catalyst had the largest surface area and the graphite nanotube structure with the least defects. It was employed for the hydrogenation of furfural to furfuryl alcohol and reached a nearly full conversion and an equivalent yield at 130 °C in 4 MPa initial H₂. The structure–function relationship study indicated that the N could interact with the neighbor Co in this catalyst and formed an electron-deficient Co center which was in favor of the adsorption of furfural in the nanotube and had high catalytic activity. The interactions between Co and N stabilized the catalyst so that it could remain stable in five runs of catalytic reactions. Full article

(This article belongs to the Special Issue Catalytic Nanomaterials for Environmental Protection and Sustainable Development)

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17 pages, 12065 KiB

Open AccessCommunication

Adjoint Algorithm Design of Selective Mode Reflecting Metastructure for BAL Applications

by Zean Li, Xunyu Zhang, Cheng Qiu, Yingshuai Xu, Zhipeng Zhou, Ziyuan Wei, Yiman Qiao, Yongyi Chen, Yubing Wang, Lei Liang, Yuxin Lei, Yue Song, Peng Jia, Yugang Zeng, Li Qin, Yongqiang Ning and Lijun Wang

Nanomaterials 2024, 14(9), 787; https://doi.org/10.3390/nano14090787 - 1 May 2024

Viewed by 1047

Abstract

Broad-area lasers (BALs) have found applications in a variety of crucial fields on account of their high output power and high energy transfer efficiency. However, they suffer from poor spatial beam quality due to multi-mode behavior along the waveguide transverse direction. In this [...] Read more.

Broad-area lasers (BALs) have found applications in a variety of crucial fields on account of their high output power and high energy transfer efficiency. However, they suffer from poor spatial beam quality due to multi-mode behavior along the waveguide transverse direction. In this paper, we propose a novel metasurface waveguide structure acting as a transverse mode selective back-reflector for BALs. In order to effectively inverse design such a structure, a digital adjoint algorithm is introduced to adapt the considerably large design area and the high degree of freedom. As a proof of the concept, a device structure with a design area of 40 × 20 μm² is investigated. The simulation results exhibit high fundamental mode reflection (above 90%), while higher-order transverse mode reflections are suppressed below 0.2%. This is, to our knowledge, the largest device structure designed based on the inverse method. We exploited such a device and the method and further investigated the device’s robustness and feasibility of the inverse method. The results are elaborately discussed. Full article

(This article belongs to the Section Theory and Simulation of Nanostructures)

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16 pages, 3376 KiB

Open AccessArticle

Enhancement of Peroxydisulfate Activation for Complete Degradation of Refractory Tetracycline by 3D Self-Supported MoS₂/MXene Nanocomplex

by Yuxia Song, Runhua Chen, Shihai Li, Shali Yu, Xiaoli Ni, Minglong Fang and Hanyun Xie

Nanomaterials 2024, 14(9), 786; https://doi.org/10.3390/nano14090786 - 30 Apr 2024

Cited by 1 | Viewed by 1502

Abstract

Antibiotic abuse, particularly the excessive use of tetracycline (TC), a drug with significant environmental risk, has gravely harmed natural water bodies and even posed danger to human health. In this study, a three-dimensional self-supported MoS₂/MXene nanohybrid with an expanded layer spacing [...] Read more.

Antibiotic abuse, particularly the excessive use of tetracycline (TC), a drug with significant environmental risk, has gravely harmed natural water bodies and even posed danger to human health. In this study, a three-dimensional self-supported MoS₂/MXene nanohybrid with an expanded layer spacing was synthesized via a facile one-step hydrothermal method and used to activate peroxydisulfate (PDS) for the complete degradation of TC. The results showed that a stronger •OH signal was detected in the aqueous solution containing MoS₂/MXene, demonstrating a superior PDS activation effect compared to MoS₂ or Ti₃C₂T_X MXene alone. Under the conditions of a catalyst dosage of 0.4 g/L, a PDS concentration of 0.4 mM, and pH = 5.0, the MoS₂/MXene/PDS system was able to fully eliminate TC within one hour, which was probably due to the presence of several reactive oxygen species (ROS) (•OH, SO₄^•−, and O₂^•−) in the system. The high TC degradation efficiency could be maintained under the influence of various interfering ions and after five cycles, indicating that MoS₂/MXene has good anti-interference and reusability performance. Furthermore, the possible degradation pathways were proposed by combining liquid chromatography–mass spectrometry (LC-MS) data and other findings, and the mechanism of the MoS₂/MXene/PDS system on the degradation process of TC was elucidated by deducing the possible mechanism of ROS generation in the reaction process. All of these findings suggest that the MoS₂/MXene composite catalyst has strong antibiotic removal capabilities with a wide range of application prospects. Full article

(This article belongs to the Special Issue Recent Advances and Research on Nanomaterials and Their Applications in Wastewater Treatment)

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20 pages, 4848 KiB

Open AccessArticle

Pyroclastic Dust from Arequipa-Peru Decorated with Iron Oxide Nanoparticles and Their Ecotoxicological Properties in Water Flea D. magna

by Juan A. Ramos-Guivar, Yacu V. Alca-Ramos, Erich V. Manrique-Castillo, F. Mendoza-Villa, Noemi-Raquel Checca-Huaman, Renzo Rueda-Vellasmin and Edson C. Passamani

Nanomaterials 2024, 14(9), 785; https://doi.org/10.3390/nano14090785 - 30 Apr 2024

Cited by 1 | Viewed by 1323

Abstract

A novel magnetic composite made of Peruvian pyroclastic dust material decorated with maghemite nanoparticles was synthesized and characterized using a variety of analytic techniques. The 13 nm maghemite nanoparticles were grown on the pyroclastic dust using the conventional coprecipitation chemical route. A short-term [...] Read more.

A novel magnetic composite made of Peruvian pyroclastic dust material decorated with maghemite nanoparticles was synthesized and characterized using a variety of analytic techniques. The 13 nm maghemite nanoparticles were grown on the pyroclastic dust using the conventional coprecipitation chemical route. A short-term acute assay was developed to study the ecotoxicological behavior of the water flea, Daphnia magna. A 24 h-lethal concentration (LC₅₀) value equal to 123.6 mg L⁻¹ was determined only for the magnetic composite. While the pyroclastic dust material did not exhibit a lethal concentration, it caused morphologically significant changes (p < 0.05) for heart and tail parameters at high concentrations. Morphologies exposed to the magnetic composite above the 24 h-LC₅₀ revealed less tolerance and significant changes in the body, heart, antenna, and eye. Hence, it affects biomarker growth and swimming. The reproduction rate was not affected by the raw pyroclastic dust material. However, the number of individuals showed a decrease with increasing composite concentrations. The present study indicates the LC₅₀ value, which can be used as a reference concentration for in-situ water cleaning with this material without damaging or changing the Daphnia magna ecosystem. Full article

(This article belongs to the Special Issue Toxicity of Engineered Nanomaterials: Current Understanding and Challenges)

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11 pages, 1427 KiB

Open AccessArticle

Towards a More Efficient Breast Cancer Therapy Using Active Human Cell Membrane-Coated Metal–Organic Frameworks

by Pablo Graván, Sara Rojas, Darina Francesca Picchi, Francisco Galisteo-González, Patricia Horcajada and Juan Antonio Marchal

Nanomaterials 2024, 14(9), 784; https://doi.org/10.3390/nano14090784 - 30 Apr 2024

Cited by 2 | Viewed by 1407

Abstract

The recent description of well-defined molecular subtypes of breast cancer has led to the clinical development of a number of successful molecular targets. Particularly, triple-negative breast cancer (TNBC) is an aggressive type of breast cancer with historically poor outcomes, mainly due to the [...] Read more.

The recent description of well-defined molecular subtypes of breast cancer has led to the clinical development of a number of successful molecular targets. Particularly, triple-negative breast cancer (TNBC) is an aggressive type of breast cancer with historically poor outcomes, mainly due to the lack of effective targeted therapies. Recent progresses in materials science have demonstrated the impressive properties of metal–organic framework nanoparticles (NPs) as antitumoral drug delivery systems. Here, in a way to achieve efficient bio-interfaces with cancer cells and improve their internalization, benchmarked MIL-100(Fe) NPs were coated with cell membranes (CMs) derived from the human TNBC cell line MDA-MB-468. The prepared CMs-coated metal–organic framework (CMs_MIL-100(Fe)) showed enhanced colloidal stability, cellular uptake, and cytotoxicity in MDA-MB-468 cells compared to non-coated NPs, paving the way for these human CMs-coated MIL-100(Fe) NPs as effective targeted therapies against the challenging TNBC. Full article

(This article belongs to the Section Inorganic Materials and Metal-Organic Frameworks)

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14 pages, 20281 KiB

Open AccessArticle

Optimizing Josephson Junction Reproducibility in 30 kV E-Beam Lithography: An Analysis of Backscattered Electron Distribution

by Arthur M. Rebello, Lucas M. Ruela, Gustavo Moreto, Naiara Y. Klein, Eldues Martins, Ivan S. Oliveira, João P. Sinnecker and Francisco Rouxinol

Nanomaterials 2024, 14(9), 783; https://doi.org/10.3390/nano14090783 - 30 Apr 2024

Viewed by 1623

Abstract

This paper explores methods to enhance the reproducibility of Josephson junctions, which are crucial elements in superconducting quantum technologies, when employing the Dolan technique in 30 kV e-beam processes. The study explores the influence of dose distribution along the bridge area on reproducibility, [...] Read more.

This paper explores methods to enhance the reproducibility of Josephson junctions, which are crucial elements in superconducting quantum technologies, when employing the Dolan technique in 30 kV e-beam processes. The study explores the influence of dose distribution along the bridge area on reproducibility, addressing challenges related to fabrication sensitivity. Experimental methods include e-beam lithography, with electron trajectory simulations shedding light on the behavior of backscattered electrons. Wedescribe the fabrication of various Josephson junction geometries and analyze the correlation between the success rates of different lithography patterns and the simulated distribution of backscattered electrons. Our findings demonstrate a success rate of up to 96.3% for the double-resist 1-step low-energy e-beam lithography process. As a means of implementation strategy, we provide a geometric example that takes advantage of simulated stability regions to administer a controlled, uniform dose across the junction area, introducing novel features to overcome the difficulties associated with fabricating bridge-like structures. Full article

(This article belongs to the Section Nanofabrication and Nanomanufacturing)

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15 pages, 2777 KiB

Open AccessArticle

Synthesis, Surface Modification and Magnetic Properties Analysis of Heat-Generating Cobalt-Substituted Magnetite Nanoparticles

by Miloš Ognjanović, Marko Bošković, Hristo Kolev, Biljana Dojčinović, Sanja Vranješ-Đurić and Bratislav Antić

Nanomaterials 2024, 14(9), 782; https://doi.org/10.3390/nano14090782 - 30 Apr 2024

Cited by 1 | Viewed by 2037

Abstract

Here, we present the results of the synthesis, surface modification, and properties analysis of magnetite-based nanoparticles, specifically Co_0.047Fe_2.953O₄ (S1) and Co_0.086Fe_2.914O₄ (S2). These nanoparticles were synthesized using the co-precipitation method at 80 °C [...] Read more.

Here, we present the results of the synthesis, surface modification, and properties analysis of magnetite-based nanoparticles, specifically Co_0.047Fe_2.953O₄ (S1) and Co_0.086Fe_2.914O₄ (S2). These nanoparticles were synthesized using the co-precipitation method at 80 °C for 2 h. They exhibit a single-phase nature and crystallize in a spinel-type structure (space group Fd

\bar{3}

m). Transmission electron microscopy analysis reveals that the particles are quasi-spherical in shape and approximately 11 nm in size. An observed increase in saturation magnetization, coercivity, remanence, and blocking temperature in S2 compared to S1 can be attributed to an increase in magnetocrystalline anisotropy due to the incorporation of Co ions in the crystal lattice of the parent compound (Fe₃O₄). The heating efficiency of the samples was determined by fitting the Box-Lucas equation to the acquired temperature curves. The calculated Specific Loss Power (SLP) values were 46 W/g and 23 W/g (under H_AC = 200 Oe and f = 252 kHz) for S1 and S2, respectively. Additionally, sample S1 was coated with citric acid (Co_0.047Fe_2.953O₄@CA) and poly(acrylic acid) (Co_0.047Fe_2.953O₄@PAA) to obtain stable colloids for further tests for magnetic hyperthermia applications in cancer therapy. Fits of the Box-Lucas equation provided SLP values of 21 W/g and 34 W/g for CA- and PAA-coated samples, respectively. On the other hand, X-ray photoelectron spectroscopy analysis points to the catalytically active centers Fe²⁺/Fe³⁺ and Co²⁺/Co³⁺ on the particle surface, suggesting possible applications of the samples as heterogeneous self-heating catalysts in advanced oxidation processes under an AC magnetic field. Full article

(This article belongs to the Collection Metallic and Metal Oxide Nanohybrids and Their Applications)

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