Molecules

Editorial

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7 pages, 220 KiB

Open AccessEditorial

Synthesis, Characterization, and Applications of Nanomaterials for Energy Conversion and Storage

by Jin Jia and Yucheng Lan

Molecules 2023, 28(21), 7383; https://doi.org/10.3390/molecules28217383 - 1 Nov 2023

Cited by 6 | Viewed by 2419

Abstract

Ever since the commencement of the Industrial Revolution in Great Britain in the mid-18th century, the annual global energy consumption from various fossil fuels, encompassing wood, coal, natural gas, and petroleum, has demonstrated an exponential surge over the past four centuries [...] Full article

(This article belongs to the Special Issue Synthesis, Characterization, and Applications of Nanomaterials for Energy Conversion and Storage)

Research

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15 pages, 4624 KiB

Open AccessArticle

Intensifying Electrochemical Activity of Ti₃C₂T_x MXene via Customized Interlayer Structure and Surface Chemistry

by Minmin Hu, Lihong Chen, Yunqi Jing, Yuanyuan Zhu, Jun Dai, Alan Meng, Changlong Sun, Jin Jia and Zhenjiang Li

Molecules 2023, 28(15), 5776; https://doi.org/10.3390/molecules28155776 - 31 Jul 2023

Cited by 7 | Viewed by 1740

Abstract

MXene, a new intercalation pseudocapacitive electrode material, possesses a high theoretical capacitance for supercapacitor application. However, limited accessible interlayer space and active sites are major challenges to achieve this high capacitance in practical application. In order to stimulate the electrochemical activity of MXene [...] Read more.

MXene, a new intercalation pseudocapacitive electrode material, possesses a high theoretical capacitance for supercapacitor application. However, limited accessible interlayer space and active sites are major challenges to achieve this high capacitance in practical application. In order to stimulate the electrochemical activity of MXene to a greater extent, herein, a method of hydrothermal treatment in NaOH solution with reducing reagent-citric acid is first proposed. After this treatment, the gravimetric capacitance of MXene exhibits a significant enhancement, about 250% of the original value, reaching 543 F g⁻¹ at 2 mV s⁻¹. This improved electrochemical performance is attributed to the tailoring of an interlayer structure and surface chemistry state. An expanded and homogenized interlayer space is created, which provides enough space for electrolyte ions storage. The –F terminations are replaced with O-containing groups, which enhances the hydrophilicity, facilitating the electrolyte’s accessibility to MXene’s surface, and makes MXene show stronger adsorption for electrolyte ion-H⁺, providing sufficient electrochemical active sites. The change in terminations further leads to the increase in Ti valence, which becomes more prone to reduction. This work establishes full knowledge of the rational MXene design for electrochemical energy storage applications. Full article

(This article belongs to the Special Issue Synthesis, Characterization, and Applications of Nanomaterials for Energy Conversion and Storage)

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14 pages, 4753 KiB

Open AccessArticle

N-Doped Porous Carbon-Nanofiber-Supported Fe₃C/Fe₂O₃ Nanoparticles as Anode for High-Performance Supercapacitors

by Li Li, Fengting Xie, Heyu Wu, Yuanyuan Zhu, Pinghua Zhang, Yanjiang Li, Hengzheng Li, Litao Zhao and Guang Zhu

Molecules 2023, 28(15), 5751; https://doi.org/10.3390/molecules28155751 - 30 Jul 2023

Cited by 6 | Viewed by 1624

Abstract

Exploring anode materials with an excellent electrochemical performance is of great significance for supercapacitor applications. In this work, a N-doped-carbon-nanofiber (NCNF)-supported Fe₃C/Fe₂O₃ nanoparticle (NCFCO) composite was synthesized via the facile carbonizing and subsequent annealing of electrospinning nanofibers containing [...] Read more.

Exploring anode materials with an excellent electrochemical performance is of great significance for supercapacitor applications. In this work, a N-doped-carbon-nanofiber (NCNF)-supported Fe₃C/Fe₂O₃ nanoparticle (NCFCO) composite was synthesized via the facile carbonizing and subsequent annealing of electrospinning nanofibers containing an Fe source. In the hybrid structure, the porous carbon nanofibers used as a substrate could provide fast electron and ion transport for the Faradic reactions of Fe₃C/Fe₂O₃ during charge–discharge cycling. The as-obtained NCFCO yields a high specific capacitance of 590.1 F g⁻¹ at 2 A g⁻¹, superior to that of NCNF-supported Fe₃C nanoparticles (NCFC, 261.7 F g⁻¹), and NCNFs/Fe₂O₃ (NCFO, 398.3 F g⁻¹). The asymmetric supercapacitor, which was assembled using the NCFCO anode and activated carbon cathode, delivered a large energy density of 14.2 Wh kg⁻¹ at 800 W kg⁻¹. Additionally, it demonstrated an impressive capacitance retention of 96.7%, even after 10,000 cycles. The superior electrochemical performance can be ascribed to the synergistic contributions of NCNF and Fe₃C/Fe₂O₃. Full article

(This article belongs to the Special Issue Synthesis, Characterization, and Applications of Nanomaterials for Energy Conversion and Storage)

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13 pages, 3813 KiB

Open AccessArticle

Phosphorus Doping Strategy-Induced Synergistic Modification of Interlayer Structure and Chemical State in Ti₃C₂T_x toward Enhancing Capacitance

by Lihong Chen, Yifan Bi, Yunqi Jing, Jun Dai, Zhenjiang Li, Changlong Sun, Alan Meng, Haijiao Xie and Minmin Hu

Molecules 2023, 28(13), 4892; https://doi.org/10.3390/molecules28134892 - 21 Jun 2023

Cited by 10 | Viewed by 1399

Abstract

Heteroatom doping is considered an effective method to substantially improve the electrochemical performance of Ti₃C₂T_x MXene for supercapacitors. Herein, a facile and controllable strategy, which combines heat treatment with phosphorous (P) doping by using sodium phosphinate (NaH₂ [...] Read more.

Heteroatom doping is considered an effective method to substantially improve the electrochemical performance of Ti₃C₂T_x MXene for supercapacitors. Herein, a facile and controllable strategy, which combines heat treatment with phosphorous (P) doping by using sodium phosphinate (NaH₂PO₂) as a phosphorus source, is used to modify Ti₃C₂T_x. The intercalated ions from NaH₂PO₂ act as “pillars” to expand the interlayer space of MXene, which is conducive to electrolyte ion diffusion. On the other hand, P doping tailors the surface electronic state of MXene, optimizing electronic conductivity and reducing the free energy of H⁺ diffusion on the MXene surface. Meanwhile, P sites with lower electronegativity owning good electron donor characteristics are easy to share electrons with H⁺, which is beneficial to charge storage. Moreover, the adopted heat treatment replaces –F terminations with O-containing groups, which enhances the hydrophilicity and provides sufficient active sites. The change in surface functional groups increases the content of high valence-stated Ti with a high electrochemical activity that can accommodate more electrons during discharge. Synergistic modification of interlayer structure and chemical state improves the possibility of Ti₃C₂T_x for accommodating more H⁺ ions. Consequently, the modified electrode delivers a specific capacitance of 510 F g⁻¹ at 2 mV s⁻¹, and a capacitance retention of 90.2% at 20 A g⁻¹ after 10,000 cycles. The work provides a coordinated strategy for the rational design of high-capacitance Ti₃C₂T_x MXene electrodes. Full article

(This article belongs to the Special Issue Synthesis, Characterization, and Applications of Nanomaterials for Energy Conversion and Storage)

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17 pages, 12332 KiB

Open AccessArticle

Effect of Electrode Spacing on the Performance of a Membrane-Less Microbial Fuel Cell with Magnetite as an Additive

by Nhlanganiso Ivan Madondo, Sudesh Rathilal, Babatunde Femi Bakare and Emmanuel Kweinor Tetteh

Molecules 2023, 28(6), 2853; https://doi.org/10.3390/molecules28062853 - 22 Mar 2023

Cited by 3 | Viewed by 2340

Abstract

A microbial fuel cell (MFC) is a bioelectrochemical system that can be employed for the generation of electrical energy under microbial activity during wastewater treatment practices. The optimization of electrode spacing is perhaps key to enhancing the performance of an MFC. In this [...] Read more.

A microbial fuel cell (MFC) is a bioelectrochemical system that can be employed for the generation of electrical energy under microbial activity during wastewater treatment practices. The optimization of electrode spacing is perhaps key to enhancing the performance of an MFC. In this study, electrode spacing was evaluated to determine its effect on the performance of MFCs. The experimental work was conducted utilizing batch digesters with electrode spacings of 2.0 cm, 4.0 cm, 6.0 cm, and 8.0 cm. The results demonstrate that the performance of the MFC improved when the electrode spacing increased from 2.0 to 6.0 cm. However, the efficiency decreased after 6.0 cm. The digester with an electrode spacing of 6.0 cm enhanced the efficiency of the MFC, which led to smaller internal resistance and greater biogas production of 662.4 mL/g VS_fed. The electrochemical efficiency analysis demonstrated higher coulombic efficiency (68.7%) and electrical conductivity (177.9 µS/cm) for the 6.0 cm, which was evident from the enrichment of electrochemically active microorganisms. With regards to toxic contaminant removal, the same digester also performed well, revealing removals of over 83% for chemical oxygen demand (COD), total solids (TS), total suspended solids (TSS), and volatile solids (VS). Therefore, these results indicate that electrode spacing is a factor affecting the performance of an MFC, with an electrode spacing of 6.0 cm revealing the greatest potential to maximize biogas generation and the degradability of wastewater biochemical matter. Full article

(This article belongs to the Special Issue Synthesis, Characterization, and Applications of Nanomaterials for Energy Conversion and Storage)

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17 pages, 3695 KiB

Open AccessArticle

Al Foil-Supported Carbon Nanosheets as Self-Supporting Electrodes for High Areal Capacitance Supercapacitors

by Jiaojiao Zheng, Bing Yan, Li Feng, Qian Zhang, Jingquan Han, Chunmei Zhang, Weisen Yang, Shaohua Jiang and Shuijian He

Molecules 2023, 28(4), 1831; https://doi.org/10.3390/molecules28041831 - 15 Feb 2023

Cited by 11 | Viewed by 2228

Abstract

Self-supporting electrode materials with the advantages of a simple operation process and the avoidance of the use any binders are promising candidates for supercapacitors. In this work, carbon-based self-supporting electrode materials with nanosheets grown on Al foil were prepared by combining hydrothermal reaction [...] Read more.

Self-supporting electrode materials with the advantages of a simple operation process and the avoidance of the use any binders are promising candidates for supercapacitors. In this work, carbon-based self-supporting electrode materials with nanosheets grown on Al foil were prepared by combining hydrothermal reaction and the one-step chemical vapor deposition method. The effect of the concentration of the reaction solution on the structures as well as the electrochemical performance of the prepared samples were studied. With the increase in concentration, the nanosheets of the samples became dense and compact. The CNS-120 obtained from a 120 mmol zinc nitrate aqueous solution exhibited excellent electrochemical performance. The CNS-120 displayed the highest areal capacitance of 6.82 mF cm⁻² at the current density of 0.01 mA cm⁻². Moreover, the CNS-120 exhibited outstanding rate performance with an areal capacitance of 3.07 mF cm⁻² at 2 mA cm⁻² and good cyclic stability with a capacitance retention of 96.35% after 5000 cycles. Besides, the CNS-120 possessed an energy density of 5.9 μWh cm⁻² at a power density of 25 μW cm⁻² and still achieved 0.3 μWh cm⁻² at 4204 μW cm⁻². This work provides simple methods to prepared carbon-based self-supporting materials with low-cost Al foil and demonstrates their potential for realistic application of supercapacitors. Full article

(This article belongs to the Special Issue Synthesis, Characterization, and Applications of Nanomaterials for Energy Conversion and Storage)

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10 pages, 2398 KiB

Open AccessArticle

Flower-Shaped Carbon Nanomaterials for Highly Efficient Solar-Driven Water Evaporation

by Nan Wang, Haifeng Xu, Jixin Yao, Bo Yang, Guang Li and Zhi Bai

Molecules 2022, 27(21), 7163; https://doi.org/10.3390/molecules27217163 - 23 Oct 2022

Cited by 5 | Viewed by 1892

Abstract

Solar-driven interface water evaporation is an energy-saving, environmentally friendly, and efficient seawater desalination and wastewater treatment technology. However, some challenges still restrict its further industrial development, such as its complex preparation, heavy metal pollution, and insufficient energy utilization. In this study, a photothermal [...] Read more.

Solar-driven interface water evaporation is an energy-saving, environmentally friendly, and efficient seawater desalination and wastewater treatment technology. However, some challenges still restrict its further industrial development, such as its complex preparation, heavy metal pollution, and insufficient energy utilization. In this study, a photothermal layer based on flower-shaped carbon nanoparticles is presented for highly efficient solar-driven interface evaporation for water treatment applications. The results show that the surface of the prepared carbon nanomaterials presents a flower-shaped structure with an excellent light absorption capacity and a large specific surface area. Moreover, the C-5.4 (Carbon-5.4) sample has an evaporation rate of 1.87 kg/m²/h and an evaporation efficiency of 87%—far higher than most photothermal materials. In addition, carbon nanomaterials have an excellent ion scavenging capacity, dye purification capacity, and outdoor practical performance. This study provides a new solution for the application of carbon nanomaterials in the field of water purification. Full article

(This article belongs to the Special Issue Synthesis, Characterization, and Applications of Nanomaterials for Energy Conversion and Storage)

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10 pages, 4474 KiB

Open AccessArticle

Mo-Doped Cu₂S Multilayer Nanosheets Grown In Situ on Copper Foam for Efficient Hydrogen Evolution Reaction

by Yajie Xie, Jianfeng Huang, Rui Xu, Danyang He, Mengfan Niu, Xiaoyi Li, Guoting Xu, Liyun Cao and Liangliang Feng

Molecules 2022, 27(18), 5961; https://doi.org/10.3390/molecules27185961 - 13 Sep 2022

Cited by 8 | Viewed by 2473

Abstract

Metal sulfide electrocatalyst is developed as a cost-effective and promising candidate for hydrogen evolution reaction (HER). In this work, we report a novel Mo-doped Cu₂S self-supported electrocatalyst grown in situ on three-dimensional copper foam via a facile sulfurization treatment method. Interestingly, [...] Read more.

Metal sulfide electrocatalyst is developed as a cost-effective and promising candidate for hydrogen evolution reaction (HER). In this work, we report a novel Mo-doped Cu₂S self-supported electrocatalyst grown in situ on three-dimensional copper foam via a facile sulfurization treatment method. Interestingly, Mo-Cu₂S nanosheet structure increases the electrochemically active area, and the large fleecy multilayer flower structure assembled by small nanosheet facilitates the flow of electrolyte in and out. More broadly, the introduction of Mo can adjust the electronic structure, significantly increase the volmer step rate, and accelerate the reaction kinetics. As compared to the pure Cu₂S self-supported electrocatalyst, the Mo-Cu₂S/CF show much better alkaline HER performance with lower overpotential (18 mV at 10 mA cm⁻², 322 mV at 100 mA cm⁻²) and long-term durability. Our work constructs a novel copper based in-situ metal sulfide electrocatalysts and provides a new idea to adjust the morphology and electronic structure by doping for promoting HER performance. Full article

(This article belongs to the Special Issue Synthesis, Characterization, and Applications of Nanomaterials for Energy Conversion and Storage)

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17 pages, 4111 KiB

Open AccessArticle

Polynaphthylimide–Azomethines Containing Triphenylamine or Carbazole Moieties with Tuned Optoelectronic Properties through Molecular Design

by Marius Soroceanu, Catalin-Paul Constantin and Mariana-Dana Damaceanu

Molecules 2022, 27(18), 5761; https://doi.org/10.3390/molecules27185761 - 6 Sep 2022

Cited by 4 | Viewed by 1611

Abstract

Polyazomethines containing electron-donor triphenylamine (TPA) or carbazole (Cbz) and electron-acceptor naphthyl(di)imide were synthesized and investigated with regard to thermal, optical and electronic features, with a focus on their modulation by molecular design. The polycondesation of an imido-based diamine with a Cbz- or TPA-based [...] Read more.

Polyazomethines containing electron-donor triphenylamine (TPA) or carbazole (Cbz) and electron-acceptor naphthyl(di)imide were synthesized and investigated with regard to thermal, optical and electronic features, with a focus on their modulation by molecular design. The polycondesation of an imido-based diamine with a Cbz- or TPA-based dialdehyde led to donor-acceptor polymers with good thermostability, up to 318 °C. These displayed good solubility in organic solvents, which enabled easy polymer processability in thin films with different molecular assemblies. The molecular order improved the charge carrier’s mobility, with a direct impact on the bandgap energy. The optical properties studied by UV–Vis absorption and fluorescence experiments showed solvent-dependence, characteristic for donor-acceptor systems. The structural parameters exerted a strong influence on the light-emissive behavior, with the prevalence of intrinsic or intramolecular charge transfer fluorescence contingent on the donor-acceptor strength and polymer geometry. All polymers showed good electroactivity, supporting both electrons and holes transport. The exchange of Cbz with TPA proved to be an efficient tool with which to decrease the bandgap energy, while that of naphthyl(di)imide with bis(naphthylimide) was beneficial for fluorescence enhancement. This study may contribute to a deeper understanding of the physico-chemistry of electronic materials so as to make them more competitive in the newest energy-related or other optoelectronic devices. Full article

(This article belongs to the Special Issue Synthesis, Characterization, and Applications of Nanomaterials for Energy Conversion and Storage)

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11 pages, 8353 KiB

Open AccessArticle

The Influence of Yb Doping and Sintering Conditions on the Magnetocaloric and Mechanical Properties of EuS

by Liang Li, Yuqi Chen, Junbao He and Aiguo Zhou

Molecules 2022, 27(17), 5660; https://doi.org/10.3390/molecules27175660 - 2 Sep 2022

Viewed by 1303

Abstract

For this work, europium monosulfide (EuS) powders were prepared by sulfurizing Eu₂O₃ powder with CS₂ gas. The synthesized EuS powders were sintered by SPS at temperatures in the 800–1600 °C range for 0.33–1 h at 50 MPa under vacuum [...] Read more.

For this work, europium monosulfide (EuS) powders were prepared by sulfurizing Eu₂O₃ powder with CS₂ gas. The synthesized EuS powders were sintered by SPS at temperatures in the 800–1600 °C range for 0.33–1 h at 50 MPa under vacuum conditions. The influences of Yb doping and sintering conditions on the magnetocaloric and mechanical properties of EuS were investigated systematically. An increase in sintering temperature caused the rise of lattice parameters of EuS, whereas Yb doping caused them to drop. SEM showed that the grain size of the EuS increased with sintering temperatures in the 1000–1400 °C range. Higher sintering temperatures can enlarge the magnetizability and saturation magnetization of EuS compact. On the contrary, Yb doping can weaken the magnetizability and saturation magnetization of EuS compact. All sintered polycrystalline EuS compacts had weaker thermomagnetic irreversibility and lower magnetic anisotropy. Full article

(This article belongs to the Special Issue Synthesis, Characterization, and Applications of Nanomaterials for Energy Conversion and Storage)

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14 pages, 4561 KiB

Open AccessArticle

Magnetic CuFe₂O₄ Nanoparticles with Pseudocapacitive Properties for Electrical Energy Storage

by Wenyu Liang, Wenjuan Yang, Sadman Sakib and Igor Zhitomirsky

Molecules 2022, 27(16), 5313; https://doi.org/10.3390/molecules27165313 - 20 Aug 2022

Cited by 21 | Viewed by 2066

Abstract

This investigation is motivated by increasing interest in the development of magnetically ordered pseudocapacitors (MOPC), which exhibit interesting magnetocapacitive effects. Here, advanced pseudocapacitive properties of magnetic CuFe₂O₄ nanoparticles in negative potential range are reported, suggesting that CuFe₂O₄ [...] Read more.

This investigation is motivated by increasing interest in the development of magnetically ordered pseudocapacitors (MOPC), which exhibit interesting magnetocapacitive effects. Here, advanced pseudocapacitive properties of magnetic CuFe₂O₄ nanoparticles in negative potential range are reported, suggesting that CuFe₂O₄ is a promising MOPC and advanced negative electrode material for supercapacitors. A high capacitance of 2.76 F cm⁻² is achieved at a low electrode resistance in a relatively large potential window of 0.8 V. The cyclic voltammograms and galvanostatic charge–discharge data show nearly ideal pseudocapacitive behavior. Good electrochemical performance is achieved at a high active mass loading due to the use of chelating molecules of ammonium salt of purpuric acid (ASPA) as a co-dispersant for CuFe₂O₄ nanoparticles and conductive multiwalled carbon nanotube (MCNT) additives. The adsorption of ASPA on different materials is linked to structural features of ASPA, which allows for different interaction and adsorption mechanisms. The combination of advanced magnetic and pseudocapacitive properties in a negative potential range in a single MOPC material provides a platform for various effects related to the influence of pseudocapacitive/magnetic properties on magnetic/pseudocapacitive behavior. Full article

(This article belongs to the Special Issue Synthesis, Characterization, and Applications of Nanomaterials for Energy Conversion and Storage)

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11 pages, 2829 KiB

Open AccessArticle

Nitrogen-Doped Porous MXene (Ti₃C₂) for Flexible Supercapacitors with Enhanced Storage Performance

by Xin Tao, Linlin Zhang, Xuedong He, Lingzi Fang, Hongyan Wang, Li Zhang, Lianghao Yu and Guang Zhu

Molecules 2022, 27(15), 4890; https://doi.org/10.3390/molecules27154890 - 30 Jul 2022

Cited by 12 | Viewed by 3326

Abstract

Flexible supercapacitors (FSCs) are limited in flexible electronics applications due to their low energy density. Therefore, developing electrode materials with high energy density, high electrochemical activity, and remarkable flexibility is challenging. Herein, we designed nitrogen-doped porous MXene (N-MXene), using melamine-formaldehyde (MF) microspheres as [...] Read more.

Flexible supercapacitors (FSCs) are limited in flexible electronics applications due to their low energy density. Therefore, developing electrode materials with high energy density, high electrochemical activity, and remarkable flexibility is challenging. Herein, we designed nitrogen-doped porous MXene (N-MXene), using melamine-formaldehyde (MF) microspheres as a template and nitrogen source. We combined it with an electrospinning process to produce a highly flexible nitrogen-doped porous MXene nanofiber (N-MXene-F) as a self-supporting electrode material and assembled it into a symmetrical supercapacitor (SSC). On the one hand, the interconnected mesh structure allows the electrolyte to penetrate the porous network to fully infiltrate the material surface, shortening the ion transport channels; on the other hand, the uniform nitrogen doping enhances the pseudocapacitive performance. As a result, the as-assembled SSC exhibited excellent electrochemical performance and excellent long-term durability, achieving an energy density of 12.78 Wh kg⁻¹ at a power density of 1080 W kg⁻¹, with long-term cycling stability up to 5000 cycles. This work demonstrates the impact of structural design and atomic doping on the electrochemical performance of MXene and opens up an exciting possibility for the fabrication of highly FSCs. Full article

(This article belongs to the Special Issue Synthesis, Characterization, and Applications of Nanomaterials for Energy Conversion and Storage)

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Review

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49 pages, 4293 KiB

Open AccessReview

An Overview of the Nano-Enhanced Phase Change Materials for Energy Harvesting and Conversion

by José Pereira, Ana Moita and António Moreira

Molecules 2023, 28(15), 5763; https://doi.org/10.3390/molecules28155763 - 30 Jul 2023

Cited by 6 | Viewed by 3347

Abstract

This review offers a critical survey of the published studies concerning nano-enhanced phase change materials to be applied in energy harvesting and conversion. Also, the main thermophysical characteristics of nano-enhanced phase change materials are discussed in detail. In addition, we carried out an [...] Read more.

This review offers a critical survey of the published studies concerning nano-enhanced phase change materials to be applied in energy harvesting and conversion. Also, the main thermophysical characteristics of nano-enhanced phase change materials are discussed in detail. In addition, we carried out an analysis of the thermophysical properties of these types of materials as well as of some specific characteristics like the phase change duration and the phase change temperature. Moreover, the fundamental improving techniques for the phase change materials for solar thermal applications are described in detail, including the use of nano-enhanced phase change materials, foam skeleton-reinforced phase change materials, phase change materials with extended surfaces, and the inclusion of high-thermal-conductivity nanoparticles in nano-enhanced phase change materials, among others. Those improvement techniques can increase the thermal conductivity of the systems by up to 100%. Furthermore, it is also reported that the exploration of phase change materials enhances the overall efficiency of solar thermal energy storage systems and photovoltaic-nano-enhanced phase change materials systems. Finally, the main limitations and guidelines for future research in the field of nano-enhanced phase change materials are summarized. Full article

(This article belongs to the Special Issue Synthesis, Characterization, and Applications of Nanomaterials for Energy Conversion and Storage)

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45 pages, 12047 KiB

Open AccessReview

Electromagnetic Radiation Effects on MgO-Based Magnetic Tunnel Junctions: A Review

by Dereje Seifu, Qing Peng, Kit Sze, Jie Hou, Fei Gao and Yucheng Lan

Molecules 2023, 28(10), 4151; https://doi.org/10.3390/molecules28104151 - 17 May 2023

Cited by 4 | Viewed by 2563

Abstract

Magnetic tunnel junctions (MTJs) have been widely utilized in sensitive sensors, magnetic memory, and logic gates due to their tunneling magnetoresistance. Moreover, these MTJ devices have promising potential for renewable energy generation and storage. Compared with Si-based devices, MTJs are more tolerant to [...] Read more.

Magnetic tunnel junctions (MTJs) have been widely utilized in sensitive sensors, magnetic memory, and logic gates due to their tunneling magnetoresistance. Moreover, these MTJ devices have promising potential for renewable energy generation and storage. Compared with Si-based devices, MTJs are more tolerant to electromagnetic radiation. In this review, we summarize the functionalities of MgO-based MTJ devices under different electromagnetic irradiation environments, with a focus on gamma-ray radiation. We explore the effects of these radiation exposures on the MgO tunnel barriers, magnetic layers, and interfaces to understand the origin of their tolerance. This review enhances our knowledge of the radiation tolerance of MgO-based MTJs, improves the design of these MgO-based MTJ devices with better tolerances, and provides information to minimize the risks of irradiation under various irradiation environments. This review starts with an introduction to MTJs and irradiation backgrounds, followed by the fundamental properties of MTJ materials, such as the MgO barrier and magnetic layers. Then, we review and discuss the MTJ materials and devices’ radiation tolerances under different irradiation environments, including high-energy cosmic radiation, gamma-ray radiation, and lower-energy electromagnetic radiation (X-ray, UV–vis, infrared, microwave, and radiofrequency electromagnetic radiation). In conclusion, we summarize the radiation effects based on the published literature, which might benefit material design and protection. Full article

(This article belongs to the Special Issue Synthesis, Characterization, and Applications of Nanomaterials for Energy Conversion and Storage)

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