NEW JOURNAL OF CHEMISTRY
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2018
·Vol. 42
·期 23
·19008-19019
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IF 3.201
Yanhua Yang,Jing-Cheng Xia,Youxuan Zheng,Yingzhong Shen,Gaozhang Gou
An efficient and readily available novel asymmetric diamine monomer containing a strongly electron-donating triphenylamine moiety and a flexibility segment was designed and synthesized through a Suzuki coupling reaction. Then, two thermally stable and highly soluble polyimides (PI(TPA-PMDA) and PI(TPA-BPDA)) were prepared and characterized. The ITO/PI(TPA-PMDA)/Al memory device exhibited write-once read-many-times (WORM) memory behavior with a threshold voltage of −1.12 V, while the PI(TPA-BPDA) memory device demonstrated flash-type memory behavior with a turn-on voltage at −0.78 V and a turn-off voltage at +1.98 V. Both devices showed high ON/OFF current ratios beyond 103 and long retention times of 4 × 103 s. Space-charge limited-current (SCLC) conduction and local filament conduction governed the OFF- and ON-state current conduction of the two memory devices, respectively. The electrical memory switching behaviors were induced by a charge transfer process under an applied electric field, and the differences between the dihedral angles and dipole moments resulted in different memory types.
研究领域:
材料科学
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电子工程
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产品关联
DOI
高影响因子
ChemistrySelect
·
2025
·Vol. 10
·期 16
·e202500414
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IF 2
Qianqian Ma,Yilin Wang,Zonglin Yi,Lijing Xie,Fangyuan Su,Guohua Sun,Gongling Hui,Wei Xie,Chengmeng Chen,Yaqin Hou
Graphical This study prepares phenolic resin-based carbon microspheres featuring small size (2–4 µm), monodispersity, and narrow particle size distribution by regulating the catalyst content. Subsequently, it explores the differences in sodium storage behavior. The optimal sample exhibits a plateau region capacity proportion of 75.6% and an initial Coulombic efficiency (ICE) of 85.02%. Phenolic resin is considered a promising precursor for advanced hard carbon anodes in sodium-ion batteries (NIBs) due to its ease of design, structural stability, and high residual carbon yield. However, the practical application of hard carbon is affected by its closed-pore content and structure. Here, we achieve fine control over the cross-linking structure of phenolic resin precursors by adjusting the catalyst content in the system, followed by high-temperature carbonization to produce phenolic resin-based carbon microspheres with small sizes (2–4 µm), monodispersity, and a narrow spherical diameter distribution. Based on this, we deeply explore the intrinsic relationship between the microstructure of these resin-based carbon microspheres and their sodium storage performance in NIBs. This strategy can provide a feasible molecular cross-linking engineering approach for the development of closed pores in phenolic resin-based hard carbon to tune electrochemical properties such as the plateau region capacity.
研究领域:
材料科学
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电化学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Bin Wang,Yazhen Yao,Wanli Wang,Yujie Xu,Yi Sun,Qiang Li,Han Hu,Mingbo Wu
Hard carbon has emerged as a promising anode material for rechargeable sodium-ion batteries, owing to its abundant precursor sources and remarkable reversible charge storage capacity. The key to achieving an extended sodium storage capacity lies in the plateau capacity largely associated with the closed-pore structure, yet a comprehensive understanding in this area remains incomplete. In our study, we utilized electron paramagnetic resonance (EPR) spectra to discern the spin state of unpaired electrons within hard carbon materials, enabling the identification of sodium storage plateau regions. Hard carbon anodes with plateau capacity predominantly exhibit delocalized spins, evident in the EPR spectrum by limited spin density and a linewidth exceeding 100 G. These spins originate from the extended aromatic structure within small-sized but curved nano-graphite and the closed-pore walls, which are crucial for plateau capacity. Conversely, hard carbon anodes exclusively possessing slope capacity are characterized by localized spins, presenting a typical narrow and intense Lorentzian EPR signal. These localized spins arise from the edge defects of the nano-graphite structure, serving as favourable sites for sodium adsorption. Our development of a methodology to discern hard carbon plateau capacity behavior based on EPR spectra presents a facile and rapid approach for advancing high-performance hard carbon materials.
研究领域:
材料科学
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电化学
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DOI
高影响因子
Journal of Energy Storage
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2023
·
IF 9.4
Hui Yong,Yiwan Chen,Yanquan Ji,Shuai Wang,Jiangwei Ma,Baosheng Liu,Jifan Hu,Yanghuan Zhang
Solid-state magnesium-based hydrogen storage encounters challenges associated with sluggish hydrogen absorption and desorption kinetics. The incorporation of catalysts is considered a promising means to improve the hydrogen absorption and desorption kinetics of these alloys. In this experiment, we prepared the Mg 80 Ni 15 Y 5 alloy via vacuum melting and incorporated TiF 3 in varying weight percentages of 1, 3, 5, and 7 wt% through ball milling . The phase composition and microstructure of the samples were analyzed and measured using X-ray diffraction meter (XRD), Transmission Electron Microscope (TEM), Selected Area Electron Diffraction (SAED), and Scanning Electron Microscope (SEM) techniques. The results revealed that the TiF 3 introduced two catalytically phases, MgF and TiF 2 . And TiF 2 transforms into TiH 2 after hydrogen absorption, which covers the surface of MgH 2 and prolongs the nucleation time of MgH 2 .Furthermore, the addition of TiF 3 made the surface of alloy markedly coarser and more irregular and few cracks, providing channels for hydrogen diffusion. This behavior optimized the kinetic performance of the alloy. It was observed that the samples containing 7 wt%TiF 3 achieved 99.2 % hydrogen saturation even in low-temperature. It's worth mentioning that the addition of 7 wt% TiF 3 to the Mg 80 Ni 15 Y 5 alloy significantly reduced the dehydrogenation activation energy to 58.5 kJ/mol, as opposed to pure magnesium with an activation energy of 158.2 kJ/mol. This substantial reduction has effectively accelerated the hydrogen absorption and desorption rates of the alloy. However, it had only a negligible impact on the thermodynamic properties of the sample with 7 wt%TiF 3 .
研究领域:
材料科学
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能源储存
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DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
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2025
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IF 19
Jianyong Pan,Jingyang Hu,Xinning Dong,Yuhui Wang,Xiaoyu Zhang,Martyn A. McLachlan,Zhongrui Wang,Jiaqi Zhang,Lijun Zhang
Memristors based on perovskite materials demonstrate significant potential for applications in information encryption and storage. However, the stability and durability of their device structures remain major challenges for commercial deployment. In this study, Mn:CsPbCl 3 perovskite nanocrystals capped with short-chain ligands are synthesized at a controlled ratio using an in situ ligand passivation strategy. Compared with long-chain ligands, short-chain ligands possess higher surface adsorption energy, which enhances nanocrystal size uniformity and enables more effective attachment to the perovskite surface at adsorption sites. This process mitigates surface defects in the nanocrystals, thereby decreasing the randomness in conductive filaments formation and enhancing device stability. Furthermore, short-chain ligand capping improves the contact at the material-electrode interface correspondingly reducing leakage current. The fabricated short-chain Al/Mn:CsPbCl 3 /FTO memristor exhibits good reconfigurable storage behavior. By adjusting the compliance current, a transition from non-volatile to volatile storage modes is successfully achieved. Leveraging the device's electrical characteristics, binary image encryption, and storage functions are realized. Overall, this work demonstrates the importance of surface defects on the operational stability of nanocrystal memristors and provides a foundation for the application of perovskite memristors in information encryption and secure transmission.
研究领域:
材料科学
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信息科学
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产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
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2018
·
IF 5.116
Xia Wu,Shi-Xi Zhao,Lü-Qiang Yu,Jing-Wei Li,En-Lai Zhao,Ce-Wen Nan
MoO 3 -P 2 O 5 glasses were prepared by a simple melt quenching method. XRD and DSC investigations confirmed the amorphous state of 60Mo-40P, 70Mo-30P and 75Mo-25P glass. Interestingly, HRTEM images revealed the inherent crystallization behavior in Mo enriched glass. The existing nanocrystals performed a synergetic effect with the glass matrix to relax the stress caused by Li ions insertion/extraction. As a result, 75Mo-25P glass with distinct nanocrystals showed excellent long cycling stability. The structural transition of MoO 3 -P 2 O 5 glass and the valence change of Mo ions during cycling were discussed. Furthermore, CV and EIS measurements were performed to elucidate the difference of redox reaction , electrons transport and ions diffusion in 75Mo-25P glass and crystalline MoO 3 . This study provides an avenue to exploit new cathode materials with long cycling life for Li-ion batteries.
研究领域:
材料科学
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电化学
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DOI
高影响因子
Journal of Energy Storage
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2024
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IF 8.9
Qirui Wang,Hongen Nian,Xiaoling Tan,Xiang Wang,Yong Deng,Xiaobin Gu,Ayoub Gounni,Yujing Zhao,Zhaoying Wang,Yongquan Zhou
Filling thermally conductive materials (TCMs) is an effectivity way to enhance the thermal conduction of phase change materials (PCMs). However, it always has negative effects on heat storage behavior of PCMs. Balance of latent heat and thermal conduction capacity plays a vital role in practical application of thermal storage management. To study the effect of dimensional features of TCM on thermal characteristic of PCM, Ag nanomaterials (Ag NMs) which including 0-dimensional Ag nanoparticles (AgNP), 1-dimensional Ag nanowires (AgNW) and 2-dimensional Ag nanosheets (AgNS) acted as TCM, were used to modify the flaky expended vermiculate (EVM-Ag NMs), a series of CH 3 COONa·3H 2 O (SAT)/EVM-Ag NM composite PCMs (SAT/EVM-Ag NM CPCMs) were prepared. It was found that the Ag NMs contributed to the phase change behavior of hydrated salts. Wherein, the SAT/EVM-AgNW CPCM possessed high latent heat (∼200.9 J/g) and great thermal reliability (heat enthalpy loss was 6.9 % after 500 thermal cycles). Besides, Ag NMs also improved the thermal conductivity of the CPCMs. The Ag NWs formed interconnected thermal highways which was benefited to enhance thermal conductivity (0.8153 W·K −1 ·m −1 ). This work provides a new strategy for simultaneously improving the thermal conductivity and heat storage behavior of PCM, finds a new perspective to explore the mechanism of TCMs on phase change behavior and heat conduction of PCM.
研究领域:
材料科学
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热能工程
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2025
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IF 8.3
Xiaoyan Wang,Yu Yuan,Jingru Lai,Xiaoli Shi,Mingye Ding
Solar-driven water splitting for hydrogen production is a pivotal technique for sustainable energy conversion. However, its efficiency is constrained by intermittent solar irradiation and rapid charge recombination. To overcome these limitations, designing a round-the-clock photocatalyst with high charge storage capacity that can still operate effectively under low light flux after sunset and promote charge carrier separation is a promising strategy. Herein, by selecting SrAl 2 O 4 :Eu 2+ /Dy 3+ persistent phosphors as electron-trapped centers and g-C 3 N 4 semiconductor as visible-light photocatalyst, SrAl 2 O 4 :Eu 2+ /Dy 3+ @g-C 3 N 4 composite has been successfully synthesized via in-situ growth strategy to form a conventional type II heterojunction photocatalyst. Benefiting from the excellent ability of charge storage and release from electron traps and the improved electron-hole separation efficiency, the designed round-the-clock photocatalyst exhibits the improved hydrogen production from 153.8 μmol g −1 h −1 to 560 μmol g −1 h −1 under visible-light irradiation, infrared-light-driven H 2 production of 932 μmol g −1 for 3 h and a dark activity of 269.1 μmol g −1 h −1 lasing for 0.5 h. This work provides a promising strategy for designing a highly efficient photocatalyst for wide-spectral-responsive and all-weather photocatalytic hydrogen production.
研究领域:
材料科学
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能源化学
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DOI
高影响因子
Chemistry-An Asian Journal
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2018
·Vol. 13
·期 14
·1784-1790
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IF 3.692
Ming Wang,Qi-jian Zhang,Zhuang Li,Hua Li,Jian-Mei Lu
Graphical Remember this? A sandwich-structured device of indium tin oxide (ITO)/polymer/aluminum exhibited different electrical behavior and threshold voltages in different solvent mixtures of different ratios (see figure). This study suggests that polymeric memory behavior can be efficiently adjusted through the use of mixed solvents. The large polydispersity index of functional pendant polymers has hindered their application in semiconductors. Herein, a novel pendant polymer with perylenediimide (PDI) in the side chains was successfully synthesized through ring-opening metathesis polymerization (ROMP) with a very low polydispersity index. The synthesized polymers were spin-coated on indium tin oxide (ITO) substrate by using a mixture of 1,2-dichlorobenzene ( o -DCB) and methanol (MeOH) solvents. The surface morphologies and intermolecular π–π stacking of the fabricated film could be adjusted through tuning of the ratio of o -DCB and MeOH, and thus, the sandwich-structured device of ITO/polymer/aluminum exhibited different electrical behavior. The threshold voltages of the devices decreased as the MeOH content was increased from 0 to 30 % (v/v); however, the device changed from being unrewritable to rewritable if the MeOH content was increased to 40 %; a probable mechanism for this process is discussed. It is hoped that this new idea of synthesizing narrow polydispersity index pendant polymers, and the fabrication of high-quality films through the use of a mixture of solvents could allow high-performance memory devices to be prepared in the future.
研究领域:
材料科学
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电子工程
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产品关联
DOI
PubMed
高影响因子
Journal of Physical Chemistry C
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2024
·
IF 3.3
Haifeng Yu,Yijia Zhou,Yanting Du,Jiayu Li,Songhao Zhao,Shuhong Wang,Haiyang Chang
A D–A conjugated polymer was used in fabrication of memory devices. However, devices using polymers as active layers alone do not lead to satisfactory results. In this paper, we have synthesized a donor–acceptor conjugated polymer by the Suzuki coupling reaction. The memory devices prepared by the polymer exhibit a ternary memory behavior. MoO3 nanoparticles have a large number of oxygen vacancies on their surface that can act as charge traps. MoO3 nanoparticles (NPs) are mixed with polymers to prepare memory devices for improved memory performance. The relationship between the mass percentage of MoO3 NPs and the storage performance and mechanism of the storage device is studied. The first and second threshold voltages of the memory device are −0.5 and −0.75 V, respectively. A current ratio of 1:102.14:104.75 for the “0″, “1”, and “2” resistance states of the device indicates a low probability of read/write errors. This work shows that polymer-embedded nanoparticle materials have practical application value in the field of next-generation nonvolatile memories.
研究领域:
材料科学
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电子工程
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DOI
高影响因子
DYES AND PIGMENTS
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2022
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IF 5.122
Ying Song,Hongyan Yao,Ye Tian,Shiyang Zhu,Shaowei Guan
In this work, three donor-acceptor contained hyperbranched copolyimides (O30-coPI, O50-coPI and O70-coPI) with different linear segment length were synthesized by varying the feed ratio of monomers . The memory device based on O30-coPI showed an unstable volatile static random access memory (SRAM) behavior, while the devices based on O50-coPI and O70-coPI with longer linear segment exhibited stable non-volatile write once read many times memory (WORM) behavior. Theoretical simulations based on density functional theory (DFT) showed that the linear segment induce a twisted conformation, which helps to stabilize the charge-separation state. As the linear segment grows, the conformation becomes more distorted, resulting in a more stable charge-separated state. Compared to O30-coPI, O50-coPI and O70-coPI have longer linear segment and more twisted conformations, thus they exhibit non-volatile memory behavior. This work demonstrates that the memory behavior can be controlled by changing the linear segment length of HB-coPI, providing a practicable strategy for the design of polymer memory materials.
研究领域:
材料科学
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电子工程
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2016
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IF 6.333
Gang Peng,Xiayin Yao,Hongli Wan,Bingxin Huang,Jingyun Yin,Fei Ding,Xiaoxiong Xu
An insightful study on the fundamental lithium storage behavior of all-solid-state lithium battery with a structure of LiNi 0.8 Co 0.15 Al 0.05 O 2 (NCA)/Li 10 GeP 2 S 12 /Li-In is carried out in this work. The relationship between electrochemical performances and particle size, surface impurities and defects of the NCA positive material is systematically investigated. It is found that a ball-milling technique can decrease the particle size and remove surface impurities of the NCA cathode while also give rise to surface defects which could be recovered by a post-annealing process. The results indicate that the interfacial resistance between the NCA and Li 10 GeP 2 S 12 is obviously decreased during the ball-milling followed by a post-annealing. Consequently, the discharge capacity of NCA in the NCA/Li 10 GeP 2 S 12 /Li-In solid-state battery is significantly enhanced, which exhibits a discharge capacity of 146 mAh g −1 at 25 °C.
研究领域:
材料科学
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电化学
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能源存储
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固态离子学
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电池技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）