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Nanomaterials
Volume 14
Issue 11
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Nanomaterials, Volume 14, Issue 11 (June-1 2024) – 93 articles

Cover Story (view full-size image): Polarisation-insensitive semiconductor optical amplifiers (SOAs) have the potential to enhance the transmission rates of all-optical networks. In this paper, we design low-polarisation SOAs with ridge widths of 4 µm, 5 µm, and 6 µm. These devices exhibit a gain bandwidth of >140 nm at 4 µm and greater output power and gain at 6 µm. The device shows a saturated output power of 233 mW at an input power of 10 dBm, as well as a polarisation sensitivity of <3 dB at −20 dBm. The device can be further optimised for a wide range of applications in all-optical networks. View this paper
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12 pages, 2649 KiB  
Article
Synthesis and Optical Properties of CdSeTe/CdZnS/ZnS Core/Shell Nanorods
by Geyu Jin, Yicheng Zeng, Xiao Liu, Qingya Wang, Jing Wei, Fangze Liu and Hongbo Li
Nanomaterials 2024, 14(11), 989; https://doi.org/10.3390/nano14110989 - 6 Jun 2024
Cited by 1 | Viewed by 1206
Abstract
Semiconductor nanorods (NRs) have great potential in optoelectronic devices for their unique linearly polarized luminescence which can break the external quantum efficiency limit of light-emitting diodes (LEDs) based on spherical quantum dots. Significant progress has been made for developing red, green, and blue [...] Read more.
Semiconductor nanorods (NRs) have great potential in optoelectronic devices for their unique linearly polarized luminescence which can break the external quantum efficiency limit of light-emitting diodes (LEDs) based on spherical quantum dots. Significant progress has been made for developing red, green, and blue light-emitting NRs. However, the synthesis of NRs emitting in the deep red region, which can be used for accurate red LED displays and promoting plant growth, is currently less explored. Here, we report the synthesis of deep red CdSeTe/CdZnS/ZnS dot-in-rod core/shell NRs via a seeded growth method, where the doping of Te in the CdSe core can extend the NR emission to the deep red region. The rod-shaped CdZnS shell is grown over CdSeTe seeds. By growing a ZnS passivation shell, the CdSeTe/CdZnS/ZnS NRs exhibit a photoluminescence emission peak at 670 nm, a full width at a half maximum of 61 nm and a photoluminescence quantum yield of 45%. The development of deep red NRs can greatly extend the applications of anisotropic nanocrystals. Full article
(This article belongs to the Special Issue Recent Advances in Halide Perovskite Nanomaterials)
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15 pages, 3445 KiB  
Article
Field Emission Properties of Cu-Filled Vertically Aligned Carbon Nanotubes Grown Directly on Thin Cu Foils
by Chinaza E. Nwanno, Arun Thapa, John Watt, Daniel Simkins Bendayan and Wenzhi Li
Nanomaterials 2024, 14(11), 988; https://doi.org/10.3390/nano14110988 - 6 Jun 2024
Cited by 1 | Viewed by 1417
Abstract
Copper-filled vertically aligned carbon nanotubes (Cu@VACNTs) were grown directly on Cu foil substrates of 0.1 mm thicknesses at different temperatures via plasma-enhanced chemical vapor deposition (PECVD). By circumventing the need for additional catalyst layers or intensive substrate treatments, our in-situ technique offers a [...] Read more.
Copper-filled vertically aligned carbon nanotubes (Cu@VACNTs) were grown directly on Cu foil substrates of 0.1 mm thicknesses at different temperatures via plasma-enhanced chemical vapor deposition (PECVD). By circumventing the need for additional catalyst layers or intensive substrate treatments, our in-situ technique offers a simplified and potentially scalable route for fabricating Cu@VACNTs with enhanced electrical and thermal properties on thin Cu foils. Comprehensive analysis using field emission scanning microscopy (FESEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS) mappings, and X-ray diffraction (XRD) revealed uniform Cu filling within the VACNTs across a range of synthesis temperatures (650 °C, 700 °C, and 760 °C). Field emission (FE) measurements of the sample synthesized at 700 °C (S700) showed low turn-on and threshold fields of 2.33 V/μm and 3.29 V/μm, respectively. The findings demonstrate the viability of thin Cu substrates in creating dense and highly conductive Cu-filled VACNT arrays for advanced electronic and nanoelectronics applications. Full article
(This article belongs to the Special Issue Advances in Carbon Nanotubes: Synthesis, Properties, and Cutting-Edge Applications)
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10 pages, 3361 KiB  
Article
Simple Synthesis of Cellulose-Based Nanocomposites as SERS Substrates for In Situ Detection of Thiram
by Boya Shi, Lian Kan, Yuliang Zhao, Shangzhong Jin and Li Jiang
Nanomaterials 2024, 14(11), 987; https://doi.org/10.3390/nano14110987 - 6 Jun 2024
Viewed by 856
Abstract
There is a growing interest in the use of flexible substrates for label-free and in situ Surface-enhanced Raman Spectroscopy (SERS) applications. In this study, a flexible SERS substrate was prepared using self-assembled Au/Ti3C2 nanocomposites deposited on a cellulose (CS) paper. [...] Read more.
There is a growing interest in the use of flexible substrates for label-free and in situ Surface-enhanced Raman Spectroscopy (SERS) applications. In this study, a flexible SERS substrate was prepared using self-assembled Au/Ti3C2 nanocomposites deposited on a cellulose (CS) paper. The Au/Ti3C2 nanocomposites uniformly wrapped around the cellulose fibers to provide a three-dimensional plasma SERS platform. The limit of detection (LOD) of CS/Au/Ti3C2 was as low as 10−9 M for 4-mercaptobenzoic acid(4-MBA) and crystal violet (CV), demonstrating good SERS sensitivity. CS/Au/Ti3C2 was used for in situ SERS detection of thiram on apple surfaces by simple swabbing, and a limit of detection of 0.05 ppm of thiram was achieved. The results showed that CS/Au/Ti3C2 is a flexible SERS substrate that can be used for the detection of thiram on apple surfaces. These results demonstrate that CS/Au/Ti3C2 can be used for the non-destructive, rapid and sensitive detection of pesticides on fruit surfaces. Full article
(This article belongs to the Special Issue Nanostructured Optoelectronic Devices and Their Applications)
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20 pages, 5344 KiB  
Review
Perspectives of Ferroelectric Wurtzite AlScN: Material Characteristics, Preparation, and Applications in Advanced Memory Devices
by Haiming Qin, Nan He, Cong Han, Miaocheng Zhang, Yu Wang, Rui Hu, Jiawen Wu, Weijing Shao, Mohamed Saadi, Hao Zhang, Youde Hu, Yi Liu, Xinpeng Wang and Yi Tong
Nanomaterials 2024, 14(11), 986; https://doi.org/10.3390/nano14110986 - 6 Jun 2024
Viewed by 2246
Abstract
Ferroelectric, phase-change, and magnetic materials are considered promising candidates for advanced memory devices. Under the development dilemma of traditional silicon-based memory devices, ferroelectric materials stand out due to their unique polarization properties and diverse manufacturing techniques. On the occasion of the 100th anniversary [...] Read more.
Ferroelectric, phase-change, and magnetic materials are considered promising candidates for advanced memory devices. Under the development dilemma of traditional silicon-based memory devices, ferroelectric materials stand out due to their unique polarization properties and diverse manufacturing techniques. On the occasion of the 100th anniversary of the birth of ferroelectricity, scandium-doped aluminum nitride, which is a different wurtzite structure, was reported to be ferroelectric with a larger coercive, remanent polarization, curie temperature, and a more stable ferroelectric phase. The inherent advantages have attracted widespread attention, promising better performance when used as data storage materials and better meeting the needs of the development of the information age. In this paper, we start from the characteristics and development history of ferroelectric materials, mainly focusing on the characteristics, preparation, and applications in memory devices of ferroelectric wurtzite AlScN. It compares and analyzes the unique advantages of AlScN-based memory devices, aiming to lay a theoretical foundation for the development of advanced memory devices in the future. Full article
(This article belongs to the Special Issue Dielectric, Ferroelectric and Piezoelectric Properties of Nanomaterials)
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14 pages, 10988 KiB  
Article
Effect of Nanoporous Molecular Sieves TS-1 on Electrical Properties of Crosslinked Polyethylene Nanocomposites
by Lirui Shi, Chong Zhang, Zhaoliang Xing, Yuanyi Kang, Weihua Han, Meng Xin and Chuncheng Hao
Nanomaterials 2024, 14(11), 985; https://doi.org/10.3390/nano14110985 - 6 Jun 2024
Cited by 1 | Viewed by 873
Abstract
Crosslinked polyethylene (XLPE) is an important polyethylene modification material which is widely used in high-voltage direct current (HVDC) transmission systems. Low-density polyethylene (LDPE) was used as a matrix to improve the thermal and electrical properties of XLPE composites through the synergistic effect of [...] Read more.
Crosslinked polyethylene (XLPE) is an important polyethylene modification material which is widely used in high-voltage direct current (HVDC) transmission systems. Low-density polyethylene (LDPE) was used as a matrix to improve the thermal and electrical properties of XLPE composites through the synergistic effect of a crosslinking agent and nanopore structure molecular sieve, TS-1. It was found that the electrical and thermal properties of the matrices were different due to the crosslinking degree and crosslinking efficiency, and the introduction of TS-1 enhanced the dielectric constants of the two matrices to 2.53 and 2.54, and the direct current (DC) resistivities were increased to 3 × 1012 and 4 × 1012 Ω·m, with the enhancement of the thermal conductivity at different temperatures. As the applied voltage increases, the DC breakdown field strength is enhanced from 318 to 363 kV/mm and 330 to 356 kV/mm. The unique nanopore structure of TS-1 itself can inhibit the injection and accumulation in the internal space of crosslinked polyethylene composites, and the pore size effect of the filler can limit the development of electron impact ionization, inhibit the electron avalanche breakdown, and improve the strength of the external applied electric field (breakdown field) that TS-1/XLPE nanocomposites can withstand. This provides a new method for the preparation of nanocomposite insulating dielectric materials for HVDC transmission systems with better performance. Full article
(This article belongs to the Special Issue Advanced Porous Nanomaterials: Synthesis, Properties, and Application)
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15 pages, 8609 KiB  
Review
A Mini Review: Phase Regulation for Molybdenum Dichalcogenide Nanomaterials
by Xiaosong Han, Zhihong Zhang and Rongming Wang
Nanomaterials 2024, 14(11), 984; https://doi.org/10.3390/nano14110984 - 6 Jun 2024
Viewed by 904
Abstract
Atomically thin two-dimensional transition metal dichalcogenides (TMDCs) have been regarded as ideal and promising nanomaterials that bring broad application prospects in extensive fields due to their ultrathin layered structure, unique electronic band structure, and multiple spatial phase configurations. TMDCs with different phase structures [...] Read more.
Atomically thin two-dimensional transition metal dichalcogenides (TMDCs) have been regarded as ideal and promising nanomaterials that bring broad application prospects in extensive fields due to their ultrathin layered structure, unique electronic band structure, and multiple spatial phase configurations. TMDCs with different phase structures exhibit great diversities in physical and chemical properties. By regulating the phase structure, their properties would be modified to broaden the application fields. In this mini review, focusing on the most widely concerned molybdenum dichalcogenides (MoX2: X = S, Se, Te), we summarized their phase structures and corresponding electronic properties. Particularly, the mechanisms of phase transformation are explained, and the common methods of phase regulation or phase stabilization strategies are systematically reviewed and discussed. We hope the review could provide guidance for the phase regulation of molybdenum dichalcogenides nanomaterials, and further promote their real industrial applications. Full article
(This article belongs to the Section 2D and Carbon Nanomaterials)
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9 pages, 3430 KiB  
Article
Enhancement of Light Efficiency of Deep-Ultraviolet Light-Emitting Diodes by Encapsulation with a 3D Photonic Crystal Reflecting Layer
by Chun-Feng Lai, Chun-Peng Lin and Yu-Chun Lee
Nanomaterials 2024, 14(11), 983; https://doi.org/10.3390/nano14110983 - 5 Jun 2024
Viewed by 1129
Abstract
Recently, UVC LEDs, which emit deep ultraviolet light, have found extensive applications across various fields. This study demonstrates the design and implementation of thin films of three-dimensional photonic crystals (3D PhCs) as reflectors to enhance the light output power (LOP) of UVC LEDs. [...] Read more.
Recently, UVC LEDs, which emit deep ultraviolet light, have found extensive applications across various fields. This study demonstrates the design and implementation of thin films of three-dimensional photonic crystals (3D PhCs) as reflectors to enhance the light output power (LOP) of UVC LEDs. The 3D PhC reflectors were prepared using the self-assembly of silica nanospheres on a UVC LED lead frame substrate via the evaporation-induced method (side) and the gravitational sedimentation method (bottom), respectively. These PhCs with the (111) crystallographic plane were deposited on the side wall and bottom of the UVC LED lead frame, acting as functional materials to reflect UVC light. The LOP of UVC LEDs with 3D PhC reflectors at a driving current of 100 mA reached 19.6 mW. This represented a 30% enhancement compared to commercial UVC LEDs with Au-plated reflectors, due to the UVC light reflection by the photonic band gaps of 3D PhCs in the (111) crystallographic plane. Furthermore, after aging tests at 60 °C and 60% relative humidity for 1000 h, the relative LOP of UVC LEDs with 3D PhC reflectors decreased by 7%, which is better than that of commercial UVC LEDs. Thus, this study offers potential methods for enhancing the light output efficiency of commercial UVC light-emitting devices. Full article
(This article belongs to the Special Issue Optical, Physical, Chemical Characteristics and Functional Modulation of Novel Quantum Materials)
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15 pages, 2965 KiB  
Article
Degradation of Perfluorododecyl-Iodide Self-Assembled Monolayers upon Exposure to Ambient Light
by Lauren Colbeck Kirby, Jayant K. Lodha, Simon Astley, Dave Skelton, Silvia Armini, Andrew Evans and Anita Brady-Boyd
Nanomaterials 2024, 14(11), 982; https://doi.org/10.3390/nano14110982 - 5 Jun 2024
Cited by 1 | Viewed by 4598 | Correction
Abstract
Perfluorododecyl iodide (I-PFC12) is of interest for area-selective deposition (ASD) applications as it exhibits intriguing properties such as ultralow surface energy, the ability to modify silicon’s band gap, low surface friction, and suitability for micro-contact patterning. Traditional photolithography is struggling to reach the [...] Read more.
Perfluorododecyl iodide (I-PFC12) is of interest for area-selective deposition (ASD) applications as it exhibits intriguing properties such as ultralow surface energy, the ability to modify silicon’s band gap, low surface friction, and suitability for micro-contact patterning. Traditional photolithography is struggling to reach the required critical dimensions. This study investigates the potential of using I-PFC12 as a way to produce contrast between the growth area and non-growth areas of a surface subsequent to extreme ultraviolet (EUV) exposure. Once exposed to EUV, the I-PFC12 molecule should degrade with the help of the photocatalytic substrate, allowing for the subsequent selective deposition of the hard mask. The stability of a vapor-deposited I-PFC12 self-assembled monolayer (SAM) was examined when exposed to ambient light for extended periods of time by using X-ray photoelectron spectroscopy (XPS). Two substrates, SiO2 and TiO2, are investigated to ascertain the suitability of using TiO2 as a photocatalytic active substrate. Following one month of exposure to light, the atomic concentrations showed a more substantial fluorine loss of 10.2% on the TiO2 in comparison to a 6.2% loss on the SiO2 substrate. This more pronounced defluorination seen on the TiO2 is attributed to its photocatalytic nature. Interestingly, different routes to degradation were observed for each substrate. Reference samples preserved in dark conditions with no light exposure for up to three months show little degradation on the SiO2 substrate, while no change is observed on the TiO2 substrate. The results reveal that the I-PFC12 SAM is an ideal candidate for resistless EUV lithography. Full article
(This article belongs to the Special Issue Trends and Prospects in Nanoscale Thin Films and Coatings)
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9 pages, 2907 KiB  
Article
Determination of Low Concentrations of Mercury Based on the Electrodeposition Time
by Kenshin Takemura, Wataru Iwasaki, Nobutomo Morita, Shinya Ohmagari, Yasunori Takaki, Hitomi Fukaura and Kazuya Kikunaga
Nanomaterials 2024, 14(11), 981; https://doi.org/10.3390/nano14110981 - 5 Jun 2024
Viewed by 1334
Abstract
Soil plays a crucial role in human health through its impact on food and habitation. However, it often contains toxic heavy metals, with mercury being particularly hazardous when methylated. Currently, high-sensitivity, rapid detection of mercury is achievable only through electrochemical measurements. These measurements [...] Read more.
Soil plays a crucial role in human health through its impact on food and habitation. However, it often contains toxic heavy metals, with mercury being particularly hazardous when methylated. Currently, high-sensitivity, rapid detection of mercury is achievable only through electrochemical measurements. These measurements require pretreatment of the soil sample and the preparation of a calibration curve tailored to the sample’s condition. In this study, we developed a method to determine the environmental standard value of mercury content in soil by significantly reducing the pretreatment process. Our approach involves analyzing current peaks from electrodeposition times using specific electrodes and solvent settings. This method demonstrates low error rates under low concentration conditions and can detect mercury levels as low as 0.5 ppb in soil leachate and reagent dilution series. This research facilitates the determination of low mercury concentrations in solutions containing various soil micro-compounds without the need for calibration curves. Full article
(This article belongs to the Special Issue Nanomaterials: Electrochemistry and Electro-Analytical Application)
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20 pages, 5756 KiB  
Article
The Janus Structure of Graphene Oxide and Its Large-Size Conductive Film Strip Pattern
by Lu Yi, Xiangnan Chen, Heng Su and Chaocan Zhang
Nanomaterials 2024, 14(11), 980; https://doi.org/10.3390/nano14110980 - 5 Jun 2024
Viewed by 711
Abstract
In this paper, the oxidation–exfoliation process of graphite is studied experimentally by the mixed-solvent method, the oxidation–exfoliation process of graphite is simulated theoretically, and it is found that Graphene Oxide (GO) is a Janus structure with inconsistent oxidation on both surfaces; hydrophilic on [...] Read more.
In this paper, the oxidation–exfoliation process of graphite is studied experimentally by the mixed-solvent method, the oxidation–exfoliation process of graphite is simulated theoretically, and it is found that Graphene Oxide (GO) is a Janus structure with inconsistent oxidation on both surfaces; hydrophilic on one side and hydrophobic on the other side. This layer structure and layer spacing are due to the inconsistent oxidation on both sides which changes with the polarity of different solvent mixtures. We used a two-phase system of benzyl alcohol and water, as well as controlling the polarity of the surface of the substrate, to achieve (using a mixed solution of GO which has a selectivity more inclined to the oil phase when the aqueous phase is present) the preparation of reduced graphene oxide patterns. We also used a complex solution of hydrogen iodide and a sodium–iodide complex solution for secondary reduction to enhance its conductivity to 8653 S/m. Full article
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12 pages, 3481 KiB  
Article
Enhanced Tunability of Dual-Band Chiral Metasurface in the Mid-Infrared Range via Slotted Nanocircuit Design
by Shengyi Wang, Hanzhuo Kuang, Wenjie Li, Yanni Wang, Hao Luo, Chengjun Li, Hua Ge, Qiu Wang and Bowen Jia
Nanomaterials 2024, 14(11), 979; https://doi.org/10.3390/nano14110979 - 5 Jun 2024
Viewed by 1085
Abstract
Multi-band circular dichroism (CD) response and tunability on the chiral metasurface are crucial for this device’s applications in sensing and detection. This work proposes a dual-band CD Au-CaF2-Au dimer elliptical metasurface absorber, where chiroptical sensing is realized by breaking the geometric [...] Read more.
Multi-band circular dichroism (CD) response and tunability on the chiral metasurface are crucial for this device’s applications in sensing and detection. This work proposes a dual-band CD Au-CaF2-Au dimer elliptical metasurface absorber, where chiroptical sensing is realized by breaking the geometric symmetry between two ellipses. The proposed metasurface can achieve high CD values of 0.8 and −0.74 for the dual-band within the 3–5 μm region, and the CD values can be manipulated by independently adjusting the geometric parameters of the metasurface. Furthermore, a slotted nanocircuit is introduced onto the metasurface to enhance its tunability by manipulating the geometry parameter in the design process, and the related mechanism is explained using an equivalent circuit model. The simulation of the sensing model revealed that the slotted nanocircuit enhances the sensor’s tunability and significantly improves its bandwidth and sensitivity, achieving peak enhancements at approximately 753 nm and 1311 nm/RIU, respectively. Due to the strong dual-band positive (and negative) responses of the CD values, flexible wavelength tunability, and nonlinear sensitivity enhancement, this design provides a new approach for the development and application of mid-infrared chiroptical devices. Full article
(This article belongs to the Special Issue Optical Composites, Nanophotonics and Metamaterials)
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10 pages, 4041 KiB  
Article
A 1.6 kV Ga2O3 Schottky Barrier Diode with a Low Reverse Current of 1.2 × 10−5 A/cm2 Enabled by Field Plates and N Ion-Implantation Edge Termination
by Xinlong Zhou, Jining Yang, Hao Zhang, Yinchi Liu, Genran Xie and Wenjun Liu
Nanomaterials 2024, 14(11), 978; https://doi.org/10.3390/nano14110978 - 5 Jun 2024
Viewed by 989
Abstract
In this work, by employing field plate (FP) and N ion-implantation edge termination (NIET) structure, the electrical performance of the β-Ga2O3 Schottky barrier diode (SBD) was greatly improved. Ten samples of vertical SBDs were fabricated to investigate the influence [...] Read more.
In this work, by employing field plate (FP) and N ion-implantation edge termination (NIET) structure, the electrical performance of the β-Ga2O3 Schottky barrier diode (SBD) was greatly improved. Ten samples of vertical SBDs were fabricated to investigate the influence of the relative positions of field plates (FPs) and ion implantation on the device performance. The device with the FP of 15 μm and the ion implantation at the edge of the Schottky electrode exhibited a breakdown voltage (Vbr) of 1616 V, a specific on-resistance (Ron,sp) of 5.11 mΩ·cm2, a power figure of merit (PFOM) of 0.511 GW/cm2, and a reverse current density of 1.2 × 10−5 A/cm2 @ −1000 V. Compared to the control device, although the Ron,sp increased by 1 mΩ·cm2, the Vbr of the device increased by 183% and the PFOM increased by 546.8%. Moreover, the reverse leakage current of the device with the FP and NIET structure decreased by three orders of magnitude. The TCAD simulation revealed that the peak electric field at the interface decreased from 7 MV/cm @ −500 V to 4.18 MV/cm @ −1000 V. These results demonstrate the great potential for the β-Ga2O3 SBD with a FP and NIET structure in power electronic applications. Full article
(This article belongs to the Special Issue Wide-Bandgap and Ultrawide-Bandgap Semiconductor Nanomaterials)
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11 pages, 3653 KiB  
Article
Defects in Nitrogen-Doped ZnO Nanoparticles and Their Effect on Light-Emitting Diodes
by Raj Deep, Toshiyuki Yoshida and Yasuhisa Fujita
Nanomaterials 2024, 14(11), 977; https://doi.org/10.3390/nano14110977 - 5 Jun 2024
Cited by 2 | Viewed by 1511
Abstract
In this study, the effect of defects on the acceptor properties of nitrogen-doped ZnO nanoparticles (NPs) was investigated through the fabrication of light-emitting diodes (LEDs). Nitrogen-doped ZnO NPs were synthesized by an arc discharge in-gas evaporation method and post-annealed at 800 °C in [...] Read more.
In this study, the effect of defects on the acceptor properties of nitrogen-doped ZnO nanoparticles (NPs) was investigated through the fabrication of light-emitting diodes (LEDs). Nitrogen-doped ZnO NPs were synthesized by an arc discharge in-gas evaporation method and post-annealed at 800 °C in an oxygen and nitrogen atmosphere. The annealed ZnO NPs were characterized by X-ray diffraction, scanning electron microscopy, Raman spectroscopy, and photoluminescence spectroscopy. It was found that the annealing of nitrogen-doped ZnO NPs in a nitrogen environment increased the number of zinc vacancies, while annealing in an oxygen environment increased the number of oxygen vacancies due to nitrogen desorption. The output characteristics of LEDs fabricated with oxygen-annealed NPs were degraded, while those with nitrogen-annealed NPs were significantly improved. From these results, the contribution of zinc vacancies to acceptor formation in ZnO NPs was confirmed for the first time in actual pn junction devices. Full article
(This article belongs to the Special Issue Synthesis, Characterization, and Application of Luminescent Nanomaterials)
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18 pages, 2250 KiB  
Review
Emerging Trends in Nanotechnology for Endometriosis: Diagnosis to Therapy
by Souvanik Talukdar, Santosh K. Singh, Manoj K. Mishra and Rajesh Singh
Nanomaterials 2024, 14(11), 976; https://doi.org/10.3390/nano14110976 - 5 Jun 2024
Cited by 1 | Viewed by 2245
Abstract
Endometriosis, an incurable gynecological disease that causes abnormal growth of uterine-like tissue outside the uterine cavity, leads to pelvic pain and infertility in millions of individuals. Endometriosis can be treated with medicine and surgery, but recurrence and comorbidities impair quality of life. In [...] Read more.
Endometriosis, an incurable gynecological disease that causes abnormal growth of uterine-like tissue outside the uterine cavity, leads to pelvic pain and infertility in millions of individuals. Endometriosis can be treated with medicine and surgery, but recurrence and comorbidities impair quality of life. In recent years, nanoparticle (NP)-based therapy has drawn global attention, notably in medicine. Studies have shown that NPs could revolutionize conventional therapeutics and imaging. Researchers aim to enhance the prognosis of endometriosis patients with less invasive and more effective NP-based treatments. This study evaluates this potential paradigm shift in endometriosis management, exploring NP-based systems for improved treatments and diagnostics. Insights into nanotechnology applications, including gene therapy, photothermal therapy, immunotherapy, and magnetic hyperthermia, offering a theoretical reference for the clinical use of nanotechnology in endometriosis treatment, are discussed in this review. Full article
(This article belongs to the Special Issue Advanced Nanomaterials in Biomedical Application (2nd Edition))
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12 pages, 3514 KiB  
Article
Long-Term Stable Cycling of Dendrite-Free Lithium Metal Batteries Using ZIF-90@PP Composite Separator
by Shuilan LYU, Xin Zhang, Sheng Huang, Shuanjin Wang, Min Xiao, Dongmei Han and Yuezhong Meng
Nanomaterials 2024, 14(11), 975; https://doi.org/10.3390/nano14110975 - 4 Jun 2024
Cited by 1 | Viewed by 1395
Abstract
Lithium metal batteries (LMBs) are anticipated to meet the demand for high energy density, but the growth of lithium dendrites seriously hinders its practical application. Herein, we constructed a kind of composite separator (ZIF-90@PP) consisting of zeolite imidazole framework-90 (ZIF-90) and polypropylene (PP) [...] Read more.
Lithium metal batteries (LMBs) are anticipated to meet the demand for high energy density, but the growth of lithium dendrites seriously hinders its practical application. Herein, we constructed a kind of composite separator (ZIF-90@PP) consisting of zeolite imidazole framework-90 (ZIF-90) and polypropylene (PP) to promote the uniform deposition of Li+ and inhibit the growth of lithium dendrites. The aldehyde groups interacting with TFSI− and the nitrogen-containing negative groups attracting Li+ of ZIF-90 can facilitate the dissociation of LiTFSI to release more Li+, thus alleviating the influence of space charge near the electrode surface and accelerating the transfer of Li+. Not only does the excellent electrolyte wettability of ZIF-90 enhance the electrolyte retention capacity of the separator, but the orderly nano-channels in ZIF-90 also restrict the free migration of anions and homogenize the distribution of Li+. Consequently, the functional separator achieves a long-term stable Li plating/stripping cycling for over 780 h at 2 mA cm−2. Moreover, an impressive average coulombic efficiency of 98.67% at 0.5 C after 300 cycles is realized by Li || LFP full cells based on ZIF-90@PP with a capacity retention rate of 71.22%. The high-rate and long cycling performance of the modified Li || LFP cells further demonstrates the advantages of the ZIF-90@PP composite separator. Full article
(This article belongs to the Topic Applications of Nanomaterials in Energy Systems, 2nd Volume)
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20 pages, 6421 KiB  
Article
Comparative Study of Callistemon citrinus (Bottlebrush) and Punica granatum (Pomegranate) Extracts for Sustainable Synthesis of Silver Nanoparticles and Their Oral Antimicrobial Efficacy
by Enas Ismail, Abubaker Mohamed, Amir Elzwawy, Ernest Maboza, Mokhotjwa Simon Dhlamini and Razia Z. Adam
Nanomaterials 2024, 14(11), 974; https://doi.org/10.3390/nano14110974 - 4 Jun 2024
Cited by 1 | Viewed by 1197
Abstract
A comparative study was applied to investigate the potential of Callistemon citrinus (bottlebrush) flower extract (BBE) and Punica granatum (pomegranate) peel extracts (PPE) for the sustainable synthesis of the silver nanoparticles, Ag-BBE and Ag-PPE, respectively. The synthesis process of Ag NPs using the [...] Read more.
A comparative study was applied to investigate the potential of Callistemon citrinus (bottlebrush) flower extract (BBE) and Punica granatum (pomegranate) peel extracts (PPE) for the sustainable synthesis of the silver nanoparticles, Ag-BBE and Ag-PPE, respectively. The synthesis process of Ag NPs using the selected extracts was applied under optimized conditions. Hence, the effect of the selected plant’s type on the different characteristics of the synthesized green Ag NPs was investigated. The UV-Vis spectroscopy revealed the presence of the characteristic silver peaks at 419 and 433 nm of the Ag-BBE and Ag-PPE, respectively. The XRD spectra reported the fcc phase formation of Ag NPs. The TEM results highlighted the morphological features of the synthesized Ag NPs. with a size range of 20–70 nm, and with 10–30 nm for Ag-BBE and Ag-PPE, correspondingly. The Raman spectra revealed characteristic silver bands in the Ag-PPE and reflected some bands related to the natural extract in the Ag-BBE sample. The antimicrobial activity and statistical analysis investigation were conducted against four selected oral pathogens (Staphylococcus aureus (SA), Candida albicans (CA), Staphylococcus epidermidis (S. epi), and Enterococcus faecalis (EF)). Both tested extracts, BBE, and PPE, revealed potential effectivity as reducing and capping agents for Ag NP green synthesis. However, the synthesized NPs demonstrated different features, depending on the used extract, reflecting the influence of the plant’s biomolecules on the nanoparticles’ properties. Full article
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16 pages, 2884 KiB  
Article
Enhanced Adsorptivity of Hexavalent Chromium in Aqueous Solutions Using CTS@nZVI Modified Wheat Straw-Derived Porous Carbon
by Tiantian Deng, Hansheng Li, Su Ding, Feng Chen, Jingbao Fu and Junwei Zhao
Nanomaterials 2024, 14(11), 973; https://doi.org/10.3390/nano14110973 - 3 Jun 2024
Cited by 1 | Viewed by 915
Abstract
Using KOH-modified wheat straw as the precursor, wheat straw biochar was produced through carbonization at 500 °C. Subsequently, a synthetic material containing nano-zero-valent iron (nZVI) was prepared via liquid phase reduction (nZVI-WSPC). To enhance its properties, chitosan (CTS) was used by crosslinking to [...] Read more.
Using KOH-modified wheat straw as the precursor, wheat straw biochar was produced through carbonization at 500 °C. Subsequently, a synthetic material containing nano-zero-valent iron (nZVI) was prepared via liquid phase reduction (nZVI-WSPC). To enhance its properties, chitosan (CTS) was used by crosslinking to form the new adsorbent named CTS@nZVI-WSPC. The impact of CTS on parameters such as mass ratio, initial pH value, and adsorbent dosage on the adsorption efficiency of Cr(VI) in solution was investigated through one-factor experiments. Isotherm adsorption and thermodynamic analysis demonstrated that the adsorption of Cr(VI) by CTS@nZVI-WSPC conforms to the Langmuir model, with a maximum adsorption capacity of 147.93 mg/g, and the adsorption process is endothermic. Kinetic analysis revealed that the adsorption process follows a pseudo-second-order kinetic model. The adsorption mechanism, as elucidated by SEM, FTIR, XPS, and XRD, suggests that the process may involve multiple mechanisms, including pore adsorption, electrostatic adsorption, chemical reduction, and surface chelation. The adsorption capacity of Cr(VI) by CTS@nZVI-WSPC remains high after five cycles. The adsorbent is simple to operate, economical, efficient, and reusable, making it a promising candidate for the treatment of Cr(VI) in water. Full article
(This article belongs to the Special Issue Nanomaterials in Water Applications)
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9 pages, 2451 KiB  
Article
Harnessing Quantum Capacitance in 2D Material/Molecular Layer Junctions for Novel Electronic Device Functionality
by Bhartendu Papnai, Ding-Rui Chen, Rapti Ghosh, Zhi-Long Yen, Yu-Xiang Chen, Khalil Ur Rehman, Hsin-Yi Tiffany Chen, Ya-Ping Hsieh and Mario Hofmann
Nanomaterials 2024, 14(11), 972; https://doi.org/10.3390/nano14110972 - 3 Jun 2024
Viewed by 998
Abstract
Two-dimensional (2D) materials promise advances in electronic devices beyond Moore’s scaling law through extended functionality, such as non-monotonic dependence of device parameters on input parameters. However, the robustness and performance of effects like negative differential resistance (NDR) and anti-ambipolar behavior have been limited [...] Read more.
Two-dimensional (2D) materials promise advances in electronic devices beyond Moore’s scaling law through extended functionality, such as non-monotonic dependence of device parameters on input parameters. However, the robustness and performance of effects like negative differential resistance (NDR) and anti-ambipolar behavior have been limited in scale and robustness by relying on atomic defects and complex heterojunctions. In this paper, we introduce a novel device concept that utilizes the quantum capacitance of junctions between 2D materials and molecular layers. We realized a variable capacitance 2D molecular junction (vc2Dmj) diode through the scalable integration of graphene and single layers of stearic acid. The vc2Dmj exhibits NDR with a substantial peak-to-valley ratio even at room temperature and an active negative resistance region. The origin of this unique behavior was identified through thermoelectric measurements and ab initio calculations to be a hybridization effect between graphene and the molecular layer. The enhancement of device parameters through morphology optimization highlights the potential of our approach toward new functionalities that advance the landscape of future electronics. Full article
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13 pages, 5349 KiB  
Article
Structural Characterization and Magnetic Behavior Due to the Cationic Substitution of Lanthanides on Ferrite Nanoparticles
by Cristóbal Pinto García, Arianne Maine, Rodrigo A. Valenzuela-Fernández, Álvaro Aliaga Cerón, Patricia Barahona Huenchumil, Octavio Peña, Inmaculada Álvarez-Serrano, Andrés Ibáñez, Francisco Melo and Antonio Galdámez Silva
Nanomaterials 2024, 14(11), 971; https://doi.org/10.3390/nano14110971 - 3 Jun 2024
Viewed by 964
Abstract
A new series of [Fe3−xLnx]O4 nanoparticles, with Ln = Gd; Dy; Lu and x = 0.05; 0.1; 0.15, was synthesized using the coprecipitation method. Analyses by X-ray diffraction (XRD), Rietveld refinement, and high-resolution transmission electron microscopy (HRTEM) [...] Read more.
A new series of [Fe3−xLnx]O4 nanoparticles, with Ln = Gd; Dy; Lu and x = 0.05; 0.1; 0.15, was synthesized using the coprecipitation method. Analyses by X-ray diffraction (XRD), Rietveld refinement, and high-resolution transmission electron microscopy (HRTEM) indicate that all phases crystallized in space group Fd3¯m, characteristic of spinels. The XRD patterns, HRTEM, scanning electron microscopy analysis (SEM-EDS), and Raman spectra showed single phases. Transmission electron microscopy (TEM), Rietveld analysis, and Scherrer’s calculations confirm that these materials are nanoparticles with sizes in the range of ~6 nm to ~13 nm. Magnetic measurements reveal that the saturation magnetization (Ms) of the as-prepared ferrites increases with lanthanide chemical substitution (x), while the coercivity (Hc) has low values. The Raman analysis confirms that the compounds are ferrites and the Ms behavior can be explained by the relationship between the areas of the signals. The magnetic measurements indicate superparamagnetic behavior. The blocking temperatures (TB) were estimated from ZFC-FC measurements, and the use of the Néel equation enabled the magnetic anisotropy to be estimated. Full article
(This article belongs to the Section Inorganic Materials and Metal-Organic Frameworks)
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17 pages, 6436 KiB  
Article
The Enhanced Photoluminescence Properties of Carbon Dots Derived from Glucose: The Effect of Natural Oxidation
by Pei Zhang, Yibo Zheng, Linjiao Ren, Shaojun Li, Ming Feng, Qingfang Zhang, Rubin Qi, Zirui Qin, Jitao Zhang and Liying Jiang
Nanomaterials 2024, 14(11), 970; https://doi.org/10.3390/nano14110970 - 3 Jun 2024
Cited by 2 | Viewed by 1131
Abstract
The investigation of the fluorescence mechanism of carbon dots (CDs) has attracted significant attention, particularly the role of the oxygen-containing groups. Dual-CDs exhibiting blue and green emissions are synthesized from glucose via a simple ultrasonic treatment, and the oxidation degree of the CDs [...] Read more.
The investigation of the fluorescence mechanism of carbon dots (CDs) has attracted significant attention, particularly the role of the oxygen-containing groups. Dual-CDs exhibiting blue and green emissions are synthesized from glucose via a simple ultrasonic treatment, and the oxidation degree of the CDs is softly modified through a slow natural oxidation approach, which is in stark contrast to that aggressively altering CDs’ surface configurations through chemical oxidation methods. It is interesting to find that the intensity of the blue fluorescence gradually increases, eventually becoming the dominant emission after prolonging the oxidation periods, with the quantum yield (QY) of the CDs being enhanced from ~0.61% to ~4.26%. Combining the microstructure characterizations, optical measurements, and ultrafiltration experiments, we hypothesize that the blue emission could be ascribed to the surface states induced by the C–O and C=O groups, while the green luminescence may originate from the deep energy levels associated with the O–C=O groups. The distinct emission states and energy distributions could result in the blue and the green luminescence exhibiting distinct excitation and emission behaviors. Our findings could provide new insights into the fluorescence mechanism of CDs. Full article
(This article belongs to the Special Issue Photofunctional Nanomaterials and Nanostructures)
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25 pages, 21401 KiB  
Article
Low-Polarization, Broad-Spectrum Semiconductor Optical Amplifiers
by Meng Zhang, Tianyi Zhang, Hui Tang, Lei Liang, Yongyi Chen, Li Qin, Yue Song, Yuxin Lei, Peng Jia, Yubing Wang, Cheng Qiu, Yuntao Cao, Yongqiang Ning and Lijun Wang
Nanomaterials 2024, 14(11), 969; https://doi.org/10.3390/nano14110969 - 2 Jun 2024
Viewed by 1327
Abstract
Polarization-insensitive semiconductor optical amplifiers (SOAs) in all-optical networks can improve the signal-light quality and transmission rate. Herein, to reduce the gain sensitivity to polarization, a multi-quantum-well SOA in the 1550 nm band is designed, simulated, and developed. The active region mainly comprises the [...] Read more.
Polarization-insensitive semiconductor optical amplifiers (SOAs) in all-optical networks can improve the signal-light quality and transmission rate. Herein, to reduce the gain sensitivity to polarization, a multi-quantum-well SOA in the 1550 nm band is designed, simulated, and developed. The active region mainly comprises the quaternary compound InGaAlAs, as differences in the potential barriers and wells of the components cause lattice mismatch. Consequently, a strained quantum well is generated, providing the SOA with gain insensitivity to the polarization state of light. In simulations, the SOA with ridge widths of 4 µm, 5 µm, and 6 µm is investigated. A 3 dB gain bandwidth of >140 nm is achieved with a 4 µm ridge width, whereas a 6 µm ridge width provides more output power and gain. The saturated output power is 150 mW (21.76 dB gain) at an input power of 0 dBm but increases to 233 mW (13.67 dB gain) at an input power of 10 dBm. The polarization sensitivity is <3 dBm at −20 dBm. This design, which achieves low polarization sensitivity, a wide gain bandwidth, and high gain, will be applicable in a wide range of fields following further optimization. Full article
(This article belongs to the Section Nanophotonics Materials and Devices)
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8 pages, 3217 KiB  
Article
Preparation of Few-Layered MoS2 by One-Pot Hydrothermal Method for High Supercapacitor Performance
by Qingling Jia, Qi Wang, Lingshuai Meng, Yujie Zhao, Jing Xu, Meng Sun, Zijian Li, Han Li, Huiyu Chen and Yongxing Zhang
Nanomaterials 2024, 14(11), 968; https://doi.org/10.3390/nano14110968 - 2 Jun 2024
Cited by 1 | Viewed by 864
Abstract
Molybdenum disulfide (MoS2), a typical layered material, has important applications in various fields, such as optoelectronics, catalysis, electronic devices, sensors, and supercapacitors. Extensive research has been carried out on few-layered MoS2 in the field of electrochemistry due to its large [...] Read more.
Molybdenum disulfide (MoS2), a typical layered material, has important applications in various fields, such as optoelectronics, catalysis, electronic devices, sensors, and supercapacitors. Extensive research has been carried out on few-layered MoS2 in the field of electrochemistry due to its large specific surface area, abundant active sites and short electron transport path. However, the preparation of few-layered MoS2 is a significant challenge. This work presents a simple one-pot hydrothermal method for synthesizing few-layered MoS2. Furthermore, it investigates the exfoliation effect of different amounts of sodium borohydride (NaBH4) as a stripping agent on the layer number of MoS2. Na+ ions, as alkali metal ions, can intercalate between layers to achieve the purpose of exfoliating MoS2. Additionally, NaBH4 exhibits reducibility, which can effectively promote the formation of the metallic phase of MoS2. Few-layered MoS2, as an electrode for supercapacitor, possesses a wide potential window of 0.9 V, and a high specific capacitance of 150 F g−1 at 1 A g−1. This work provides a facile method to prepare few-layered two-dimensional materials for high electrochemical performance. Full article
(This article belongs to the Special Issue Nanomaterials for Supercapacitors)
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15 pages, 14126 KiB  
Article
The Role of Oxygen Vacancies in Phase Transition and the Optical Absorption Properties within Nanocrystalline ZrO2
by Jing Ouyang, Yonghui Peng, Wentao Zhou, Xianfeng Liang, Gang Wang, Qi Zhang and Bo Yuan
Nanomaterials 2024, 14(11), 967; https://doi.org/10.3390/nano14110967 - 2 Jun 2024
Cited by 1 | Viewed by 1144
Abstract
Zirconia (ZrO2) nanoparticles were synthesized using a solvothermal method under varying synthesis conditions, namely acidic, neutral, and alkaline. X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) were leveraged to investigate the phase evolution and topographical features in detail. The [...] Read more.
Zirconia (ZrO2) nanoparticles were synthesized using a solvothermal method under varying synthesis conditions, namely acidic, neutral, and alkaline. X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) were leveraged to investigate the phase evolution and topographical features in detail. The resulting crystal phase structures and grain sizes exhibited substantial variation based on these conditions. Notably, the acidic condition fostered a monoclinic phase in ZrO2, while the alkaline condition yielded a combination of tetragonal and monoclinic phases. In contrast, ZrO2 obtained under neutral conditions demonstrated a refinement in grain sizes, constrained within a 1 nm scale upon an 800 °C thermal treatment. This was accompanied by an important transformation from a monoclinic phase to tetragonal phase in the ZrO2. Furthermore, a rigorous examination of XPS data and a UV-visible spectrometer (UV-vis) analysis revealed the significant role of oxygen vacancies in phase stabilization. The notable emergence of new energy bands in ZrO2, in stark contrast to the intrinsic bands observed in a pure monoclinic sample, are attributed to these oxygen vacancies. This research offers valuable insights into the novel energy bands, phase stability, and optical absorption properties influenced by oxygen vacancies in ZrO2. Moreover, it proposes an innovative energy level model for zirconia, underpinning its applicability in diverse technological areas. Full article
(This article belongs to the Special Issue Synthesis and Application of Optical Nanomaterials)
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11 pages, 3884 KiB  
Article
Encapsulation and Evolution of Polyynes Inside Single-Walled Carbon Nanotubes
by Kunpeng Tang, Yinong Li, Yingzhi Chen, Weili Cui, Zhiwei Lin, Yifan Zhang and Lei Shi
Nanomaterials 2024, 14(11), 966; https://doi.org/10.3390/nano14110966 - 2 Jun 2024
Viewed by 1056
Abstract
Polyyne is an sp-hybridized linear carbon chain (LCC) with alternating single and triple carbon–carbon bonds. Polyyne is very reactive; thus, its structure can be easily damaged through a cross-linking reaction between the molecules. The longer the polyyne is, the more unstable it becomes. [...] Read more.
Polyyne is an sp-hybridized linear carbon chain (LCC) with alternating single and triple carbon–carbon bonds. Polyyne is very reactive; thus, its structure can be easily damaged through a cross-linking reaction between the molecules. The longer the polyyne is, the more unstable it becomes. Therefore, it is difficult to directly synthesize long polyynes in a solvent. The encapsulation of polyynes inside carbon nanotubes not only stabilizes the molecules to avoid cross-linking reactions, but also allows a restriction reaction to occur solely at the ends of the polyynes, resulting in long LCCs. Here, by controlling the diameter of single-walled carbon nanotubes (SWCNTs), polyynes were filled with high yield below room temperature. Subsequent annealing of the filled samples promoted the reaction between the polyynes, leading to the formation of long LCCs. More importantly, single chiral (6,5) SWCNTs with high purity were used for the successful encapsulation of polyynes for the first time, and LCCs were synthesized by coalescing the polyynes in the (6,5) SWCNTs. This method holds promise for further exploration of the synthesis of property-tailored LCCs through encapsulation inside different chiral SWCNTs. Full article
(This article belongs to the Special Issue Preparation, Properties, and Applications of One-Dimensional Carbon Nanomaterials)
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18 pages, 2939 KiB  
Article
Structural, Electrical, and Optical Properties of Single-Walled Carbon Nanotubes Synthesized through Floating Catalyst Chemical Vapor Deposition
by Melorina Dolafi Rezaee, Biplav Dahal, John Watt, Mahir Abrar, Deidra R. Hodges and Wenzhi Li
Nanomaterials 2024, 14(11), 965; https://doi.org/10.3390/nano14110965 - 2 Jun 2024
Viewed by 2113
Abstract
Single-walled carbon nanotube (SWCNT) thin films were synthesized by using a floating catalyst chemical vapor deposition (FCCVD) method with a low flow rate (200 sccm) of mixed gases (Ar and H2). SWCNT thin films with different thicknesses can be prepared by [...] Read more.
Single-walled carbon nanotube (SWCNT) thin films were synthesized by using a floating catalyst chemical vapor deposition (FCCVD) method with a low flow rate (200 sccm) of mixed gases (Ar and H2). SWCNT thin films with different thicknesses can be prepared by controlling the collection time of the SWCNTs on membrane filters. Transmission electron microscopy (TEM) showed that the SWCNTs formed bundles and that they had an average diameter of 1.46 nm. The Raman spectra of the SWCNT films suggested that the synthesized SWCNTs were very well crystallized. Although the electrical properties of SWCNTs have been widely studied so far, the Hall effect of SWCNTs has not been fully studied to explore the electrical characteristics of SWCNT thin films. In this research, Hall effect measurements have been performed to investigate the important electrical characteristics of SWCNTs, such as their carrier mobility, carrier density, Hall coefficient, conductivity, and sheet resistance. The samples with transmittance between 95 and 43% showed a high carrier density of 1021–1023 cm−3. The SWCNTs were also treated using Brønsted acids (HCl, HNO3, H2SO4) to enhance their electrical properties. After the acid treatments, the samples maintained their p-type nature. The carrier mobility and conductivity increased, and the sheet resistance decreased for all treated samples. The highest mobility of 1.5 cm2/Vs was obtained with the sulfuric acid treatment at 80 °C, while the highest conductivity (30,720 S/m) and lowest sheet resistance (43 ohm/square) were achieved with the nitric acid treatment at room temperature. Different functional groups were identified in our synthesized SWCNTs before and after the acid treatments using Fourier-Transform Infrared Spectroscopy (FTIR). Full article
(This article belongs to the Special Issue Advances in Carbon Nanotubes: Synthesis, Properties, and Cutting-Edge Applications)
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15 pages, 4613 KiB  
Article
Photonic Nanochains for Continuous Glucose Monitoring in Physiological Environment
by Gongpu Shi, Luying Si, Jinyang Cai, Hao Jiang, Yun Liu, Wei Luo, Huiru Ma and Jianguo Guan
Nanomaterials 2024, 14(11), 964; https://doi.org/10.3390/nano14110964 - 1 Jun 2024
Viewed by 885
Abstract
Diabetes is a common disease that seriously endangers human health. Continuous glucose monitoring (CGM) is important for the prevention and treatment of diabetes. Glucose-sensing photonic nanochains (PNCs) have the advantages of naked-eye colorimetric readouts, short response time and noninvasive detection of diabetes, showing [...] Read more.
Diabetes is a common disease that seriously endangers human health. Continuous glucose monitoring (CGM) is important for the prevention and treatment of diabetes. Glucose-sensing photonic nanochains (PNCs) have the advantages of naked-eye colorimetric readouts, short response time and noninvasive detection of diabetes, showing immense potential in CGM systems. However, the developed PNCs cannot disperse in physiological environment at the pH of 7.4 because of their poor hydrophilicity. In this study, we report a new kind of PNCs that can continuously and reversibly detect the concentration of glucose (Cg) in physiological environment at the pH of 7.4. Polyacrylic acid (PAA) added to the preparation of PNCs forms hydrogen bonds with polyvinylpyrrolidone (PVP) in Fe3O4@PVP colloidal nanoparticles and the hydrophilic monomer N-2-hydroxyethyl acrylamide (HEAAm), which increases the content of PHEAAm in the polymer shell of prepared PNCs. Moreover, 4-(2-acrylamidoethylcarbamoyl)-3-fluorophenylboronic acid (AFPBA), with a relatively low pKa value, is used as the glucose-sensing monomer to further improve the hydrophilicity and glucose-sensing performances of PNCs. The obtained Fe3O4@(PVP-PAA)@poly(AFPBA-co-HEAAm) PNCs disperse in artificial serum and change color from yellow-green to red when Cg increases from 3.9 mM to 11.4 mM, showing application potential for straightforward CGM. Full article
(This article belongs to the Section Nanofabrication and Nanomanufacturing)
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11 pages, 2151 KiB  
Article
Influence of Hole Transport Layers on Buried Interface in Wide-Bandgap Perovskite Phase Segregation
by Fangfang Cao, Liming Du, Yongjie Jiang, Yangyang Gou, Xirui Liu, Haodong Wu, Junchuan Zhang, Zhiheng Qiu, Can Li, Jichun Ye, Zhen Li and Chuanxiao Xiao
Nanomaterials 2024, 14(11), 963; https://doi.org/10.3390/nano14110963 - 1 Jun 2024
Viewed by 935
Abstract
Light-induced phase segregation, particularly when incorporating bromine to widen the bandgap, presents significant challenges to the stability and commercialization of perovskite solar cells. This study explores the influence of hole transport layers, specifically poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine (PTAA) and [4-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphonic acid (Me-4PACz), on the dynamics of [...] Read more.
Light-induced phase segregation, particularly when incorporating bromine to widen the bandgap, presents significant challenges to the stability and commercialization of perovskite solar cells. This study explores the influence of hole transport layers, specifically poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine (PTAA) and [4-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphonic acid (Me-4PACz), on the dynamics of phase segregation. Through detailed characterization of the buried interface, we demonstrate that Me-4PACz enhances perovskite photostability, surpassing the performance of PTAA. Nanoscale analyses using in situ Kelvin probe force microscopy and quantitative nanomechanical mapping techniques elucidate defect distribution at the buried interface during phase segregation, highlighting the critical role of substrate wettability in perovskite growth and interface integrity. The integration of these characterization techniques provides a thorough understanding of the impact of the buried bottom interface on perovskite growth and phase segregation. Full article
(This article belongs to the Special Issue Advancing the Sustainable Application of Nanostructured Materials in Solar Cells)
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16 pages, 3407 KiB  
Article
Performance Projection of Vacuum Gate Dielectric Doping-Free Carbon Nanoribbon/Nanotube Field-Effect Transistors for Radiation-Immune Nanoelectronics
by Khalil Tamersit, Abdellah Kouzou, José Rodriguez and Mohamed Abdelrahem
Nanomaterials 2024, 14(11), 962; https://doi.org/10.3390/nano14110962 - 1 Jun 2024
Cited by 1 | Viewed by 958
Abstract
This paper investigates the performance of vacuum gate dielectric doping-free carbon nanotube/nanoribbon field-effect transistors (VGD-DL CNT/GNRFETs) via computational analysis employing a quantum simulation approach. The methodology integrates the self-consistent solution of the Poisson solver with the mode space non-equilibrium Green’s function (NEGF) in [...] Read more.
This paper investigates the performance of vacuum gate dielectric doping-free carbon nanotube/nanoribbon field-effect transistors (VGD-DL CNT/GNRFETs) via computational analysis employing a quantum simulation approach. The methodology integrates the self-consistent solution of the Poisson solver with the mode space non-equilibrium Green’s function (NEGF) in the ballistic limit. Adopting the vacuum gate dielectric (VGD) paradigm ensures radiation-hardened functionality while avoiding radiation-induced trapped charge mechanisms, while the doping-free paradigm facilitates fabrication flexibility by avoiding the realization of a sharp doping gradient in the nanoscale regime. Electrostatic doping of the nanodevices is achieved via source and drain doping gates. The simulations encompass MOSFET and tunnel FET (TFET) modes. The numerical investigation comprehensively examines potential distribution, transfer characteristics, subthreshold swing, leakage current, on-state current, current ratio, and scaling capability. Results demonstrate the robustness of vacuum nanodevices for high-performance, radiation-hardened switching applications. Furthermore, a proposal for extrinsic enhancement via doping gate voltage adjustment to optimize band diagrams and improve switching performance at ultra-scaled regimes is successfully presented. These findings underscore the potential of vacuum gate dielectric carbon-based nanotransistors for ultrascaled, high-performance, energy-efficient, and radiation-immune nanoelectronics. Full article
(This article belongs to the Section Nanoelectronics, Nanosensors and Devices)
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11 pages, 1432 KiB  
Article
Effects of Composition and Polymerization Conditions on the Electro-Optic Performance of Liquid Crystal–Polymer Composites Doped with Ferroelectric Nanoparticles
by Gaby Nordendorf, Gisela Jünnemann-Held, Alexander Lorenz and Heinz-Siegfried Kitzerow
Nanomaterials 2024, 14(11), 961; https://doi.org/10.3390/nano14110961 - 31 May 2024
Cited by 1 | Viewed by 705
Abstract
The presence of a polymer network and/or the addition of ferroelectric nanoparticles to a nematic liquid crystal are found to lower transition temperatures and birefringence, which indicates reduced orientational order. In addition, the electro-optic switching voltage is considerably increased when a polymer network [...] Read more.
The presence of a polymer network and/or the addition of ferroelectric nanoparticles to a nematic liquid crystal are found to lower transition temperatures and birefringence, which indicates reduced orientational order. In addition, the electro-optic switching voltage is considerably increased when a polymer network is formed by in situ polymerization in the nematic state. However, the resulting polymer network liquid crystal switches at similar voltages as the neat liquid crystal when polymerization is performed at an elevated temperature in the isotropic state. When nanoparticle dispersions are polymerized at an applied DC voltage, the transition temperatures and switching voltages are reduced, yet they are larger than those observed for polymer network liquid crystals without nanoparticles polymerized in the isotropic phase. Full article
(This article belongs to the Special Issue Nanoelectronics: Materials, Devices and Applications)
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14 pages, 2659 KiB  
Article
Synthesis, Structural Characterization, and Infrared Analysis of Double Perovskites Pr2NiMnO6, Gd2NiMnO6, and Er2NiMnO6 Functional Nano-Ceramics
by Mebark Elhamel, Zoulikha Hebboul, Djamal Benbertal, Pablo Botella and Daniel Errandonea
Nanomaterials 2024, 14(11), 960; https://doi.org/10.3390/nano14110960 - 30 May 2024
Viewed by 873
Abstract
We synthesized Pr2NiMnO6, Gd2NiMnO6, and Er2NiMnO6 double perovskites in a nano-ceramic form by a sol–gel method. By means of room-temperature X-ray powder diffraction measurements, we determined the crystal structure of the three [...] Read more.
We synthesized Pr2NiMnO6, Gd2NiMnO6, and Er2NiMnO6 double perovskites in a nano-ceramic form by a sol–gel method. By means of room-temperature X-ray powder diffraction measurements, we determined the crystal structure of the three compounds, which is monoclinic, corresponding to a double perovskite structure, described by space group P21/n structure. From the determined structures, the bulk moduli were estimated to be 173–179 GPa. The average size particle of nanoparticles was determined from X-ray diffraction by the Langford method plot and by the Scherrer formula. The morphology and homogeneity of nanoparticles were analyzed by scanning electron microscopy. We found that they form compact agglomerations of approximately 200 nm in diameter. Fourier transform infrared spectroscopy measurements were performed, determining the absorption spectrum. The assignment of the measured infrared absorption bands is discussed. Full article
(This article belongs to the Section Nanocomposite Materials)
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