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Nano Research 2021年第11期14卷 3773-3794页

作者： Yong Xu Muhan Cao Shaoming Huang Guangzhou Key Laboratory of Low-Dimensional materials and energy Storage Devices Collaborative Innovation Center of Advanced Energy MaterialsSchool of Materials and EnergyGuangdong University of TechnologyGuangzhou510006China Institute of Functional Nano&Soft materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials and DevicesSoochow UniversitySuzhou215123China

Metal halide perovskite nanocrystals have attracted great attention of researchers due to their unique optoelectronic properties such as high photoluminescence quantum yield (PLQY), narrow full width at half-maximum (FWHM), long exciton diffusion length and high carrier mobility, which have been widely used in diverse fields including solar cells, photodetectors, light-emitting diodes, and lasers. Very recently, metal halide perovskites have emerged as a new class of materials in photocatalysis due to their promising photocatalytic performance. In this review, we summarize the recent advances on synthesis, modification and functionalization, with a specific focus on the photocatalytic application of metal halide perovskite nanocrystals. Finally, a brief outlook is proposed to point out the challenges in this emerging area. The goal of this view is to introduce the photocatalytic application of the metal halide perovskites and motivate researchers from different fields to explore more potentials in catalysis.

关键词： metal halide perovskite nanocrystals synthesis modification functionalization photocatalytic application

Thermal shock damage behavior of CVD ZnS by oxygen propane flame: A numerical and experimental study

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Chinese Journal of Aeronautics 2014年第2期27卷 266-271页

作者： Liu Yuanchun He Yurong Tian Fenglin Zhu Jiaqi School of energy Science & Engineering Harbin Institute of Technology center of Composite materials Harbin Institute of Technology

Chemical vapor deposition zinc sulfide （CVD ZnS） is widely used as an infrared window material to transmit infrared signals, keep the aerodynamic shape and protect its imaging system, which often suffers high temperature and complicated thermal stresses. The purpose of this paper is to investigate the thermal shock damage of CVD ZnS through a finite element method and oxygen propane flame experiments. The finite element model is developed to simulate the temperature and thermal stress fields by an oxygen propane flame. Then, the thermal shock experiments are performed to investigate the thermal shock damage behavior. The results show that the temperature rising rate of the shock surface is fast during the initial heating stage resulting in high thermal stress. After the thermal shock experiment, the scanning electron microscope （SEM） photographs shows that the shock surface of the specimen becomes rough and the microcracks occur in the thermal shock zone. Good agreements are achieved between the numerical solutions and the experimental results.

关键词： CVD ZnS Damage behavior Finite element method,Oxygen propane flame Thermal shock

Effect of Y_2O_3 on the crystallization kinetics of TiO_2 nucleated LAS glass for the production of nanocrystalline transparent glass ceramics

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International Journal of Minerals,Metallurgy and materials 2013年第5期20卷 450-455页

作者： Mohammad Sadegh Shakeri materials and energy Research center (MERC) P.O. Box 31779-83634KarajIran

Crystallization kinetics of metastable B-quartz solid solution as a desirable phase for the production of trans- parent lithium aluminosilicate （LAS） glass ceramics was investigated in the presence of Y203. Accordingly, differential thermal analysis scans were performed thoroughly to study the mechanism of crystallization kinetics. The aim of this investigation is to discover the complicated mechanism of crystallization process in the presence of co-additives and ac- cordingly find a way for increasing the transparency of glass ceramics. It is shown that the bulk （3D） growth is intensively increased by the enhancement of Y203. Then again, reducing nucleation and increasing growth mechanisms were recog- nized for the LAS system in the presence of Y2O3. Results of the investigation illustrate that when co-additives are added to glasses, it is necessary to nucleate the optical component separately before the growth process.

关键词： glass ceramics lithium aluminosilicate yttria crystallization kinetics nanocrystals transparency

Static and dynamic properties of polymer brush with topological ring structures: Molecular dynamic simulation

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Chinese Physics B 2016年第10期25卷 252-258页

作者：万吴兵吕红红候格吴晨旭 Institute of Softmatter and Biometrics Xiamen University Collaborative Innovation center of Chemistry for energy materials Xiamen University

By defining a topological constraint value（rn）,the static and dynamic properties of a polymer brush composed of moderate or short chains with different topological ring structures are studied using molecular dynamics simulation,and a comparison with those of linear polymer brush is also *** the center-of-mass height of the ring polymer brush scaled by chain length h;,there is no significant difference of exponent from that of a linear brush in the small topological constraint ***,as the topological constraint becomes stronger,one obtains a smaller *** is found that there exists a master scaling power law of the total stretching energy scaled by chain length N for moderate chain length regime,F;p;,for ring polymer brushes,but with a larger exponent v than 5/6,indicating an influence of topological constraint to the dynamic properties of the system.A topological invariant of free energy scaled by（c）;is found.

关键词： ring polymer topological invariant scaling

Magnetic properties of Sn-substituted Ni-Zn ferrites synthesized from nano-sized powders of NiO, ZnO, Fe2O3, and SnO2

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Chinese Physics B 2017年第7期26卷 377-382页

作者： M A Ali M M Uddin M N I Khan F U Z Chowdhury S M Hoque S I Liba Department of Physics Chittagong University of Engineering and Technology (CUET) materials Science Division Atomic Energy Center

A series of Ni0.6-x/2Zn0.4-x/2SnxFe2O4(x = 0.0, 0.05, 0.1, 0.15, 0.2, and 0.3)(NZSFO) ferrite composities have been synthesized from nano powders using a standard solid state reaction technique. The spinel cubic structure of the investigated samples has been confirmed by x-ray diffraction(XRD). The magnetic properties such as saturation magnetization(Ms),remanent magnetization(Mr), coercive field(Hc), and Bohr magneton(μ) are calculated from the hysteresis loops. The value of Msis found to decrease with increasing Sn content in the samples. This change is successfully explained by the variation of A-B interaction strength due to Sn substitution in different sites. The compositional stability and quality of the prepared ferrite composites have also been endorsed by the fairly constant initial permeability(μ’) over a wide range of frequency. The decreasing trend of μ’ with increasing Sn content has been observed. Curie temperature TChas been found to increase with the increase in Sn content. A wide spread frequency utility zone indicates that the NZSFO can be considered as a good candidate for use in broadband pulse transformers and wide band read-write heads for video recording. The composition of x = 0.05 shows unusual results and the possible reason is also mentioned with the established formalism.

关键词： magnetic properties saturation magnetization permeability Curie temperature

Synthesis ofα-Li FeO_(2)/Graphene nanocomposite via layer by layer self-assembly strategy for lithium-ion batteries with excellent electrochemical performance

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Journal of materials Science & Technology 2020年第20期52卷 173-181页

作者： Youzuo Hu Hongyuan Zhao Ming Tan Jintao Liu Xiaohui Shu Meiling Zhang Shanshan Liu Qiwen Ran Hao Li Xingquan Liu R&D center for New energy materials and Integrated energy Devices University of Electronic Science and Technology of ChinaChengdu 610054China

As a potential alternative cathode material,α-LiFeO2 suffers a realization handicap,mainly due to its poor electrical conductivity and low lithium ion diffusion *** this work,we have successfully synthesized α-LiFeO2/rGO nanocomposite through a layer by layer self-assembly modification process and annealing *** to the strong electrostatic attraction between opposite cha rged spices,α-LiFeO2 nanoparticles were homogeneously dispersed on the graphene sheet to form a typical interconnected conducting network which was bene ficial for electronic conductivity and ionic diffu *** comparison to pristine α-LiFeO2,the α-LiFeO2/rGO displayed an excellent electrochemical perfo rmance with average discharge capacities of 238.9,187.2,178.4,121.8 and 99.5 mA hg^-1 at 0.1,0.2,0.5,1 and 2 C,***,the specific capacity retained 164.9 mA h g^-1 and 107.98 mA h g^-1 after 50 cycles at 0.5 C and 1 C,*** remarkable progress in rate capability and cycling ability of this new nanocomposite developed a new approach to improve the electrochemical performance of α-LiFeO2.

关键词： α-LiFeO_(2) Lithium ion battery Graphene Layer by layer self-assembly

In-situ formation of Li_(0.5)Mn_(0.5)O coating layer through defect controlling for high performance Li-rich manganese-based cathode material

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Journal of energy Chemistry 2022年第8期31卷 384-391,I0010页

作者： Aipeng Zhu Qin Wang Yin Zhang Yueyin Zhang Xiaogang He Kaipeng Wu Hao Wu Qian Wang Wenlong Cai Yun Zhang Department of Advanced energy materials College of Materials Science and EngineeringSichuan UniversityChengdu 610064SichuanChina Engineering Research center of Alternative energy materials&Devices Ministry of EducationSichuan UniversityChengdu 610064SichuanChina

Li-rich layered oxide of Li_(1.2)Mn_(0.6)Ni_(0.2)O_(2)(LMNO)with a considerable specific capacity and higher voltage is regarded as a kind of promising cathode ***,it suffers from transition metal ion dissolution and oxygen escape that leads to rapid capacity *** addition,the poor lithium-ion diffusion kinetics gives rise to unsatisfied rate ***,a stable layer of Li_(0.5)Mn_(0.5)O(LMO)out of LMNO is in-situ constructed through acetic passivation and following calcination *** generated defect structure in the composite material exhibits fast ion diffusion kinetics and the produced LMO layer can stabilize the substructure,resulting in elevated cycling stability and rate *** specific,the LMNO@LMO material exhibits a high initial coulombic efficiency of 80.3%and remarkable capacity retention of 80.7%after 200 cycles at 1 ***,the composite material reveals prominent rate performance that delivers discharge capacities of 158 and 131 m Ah g^(-1) at 5 and 10 C,*** last,this study presents a new approach to optimizing the Li-rich cathode materials.

关键词： Defect Interfacial stability Li_(0.5)Mn_(0.5)O Li-rich layered oxides Lithium-ion batteries

A direct H2O2 production based on hollow porous carbon sphere-sulfur nanocrystal composites by confinement effect as oxygen reduction electrocatalysts

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Nano Research 2019年第10期12卷 2614-2622页

作者： Guanyu Chen Jiwei Liu Qingqing Li Pengfei Guan Xuefeng Yu Linshen Xing Jie Zhang Renchao Che Laboratory of Advanced materials Department of Materials Science and Collaborative Innovation Center of Chemistry for Energy Materials(iChem)Fudan UniversityShanghai 200438China Beijing Computational Science Research center Beijing 100193China Innovative center for Advanced materials(ICAM) Hangzhou Dianzi UniversityHangzhou 310012China

Carbon-sulfur composites have draw n in creasing interest in various fields including electrocatalysis because of their unique ***,carb on-sulfur composite with tiny sulfur nano crystals has still received little ***,hollow porous carb on sphere-sulfur composite(HPCS-S)which possesses excellent electrochemical performance towards H2O2 has been prepared for the first time via a simple silica template *** 2-5 nm sulfur nan ocrystals being restricted in the cha nnel of the hollow porous carb on spheres are un der a strong compressive stress,which was further con firmed by high-resoluti on tran smissi on electr on microscopy(HRTEM)and *** HPCS-S nano crystals show better con ductivity tha n amorphous sulfur clusters because of the reducti on of the steric hindrance which efficie ntly promotes the electron ***,the higher activity and selectivity towards the 2e^oxygen reduction reaction(ORR)to H2O2 in alkaline solution was *** H2O2 selectivity rises from 20%to over 70%after the sulfur addition and the H2O2 production rate achieves 183.99 mmol-gcataiyst-1 with the Faradaic efficiency of 70%.Furthermore,performance enhancement mechanism was also investigated using the den sity functional theory(DFT)calculatio *** the in troduci ng of sulfur nano crystals,the appeara nee of S-S bond greatly decreases the overpotential compared with S-doping,which results in significant enhancement of the electrocatalytic ***,the HPCS-S can be an efficient H2O2 production electrocatalyst in alkaline solution.

关键词： sulfur nanocrystal hydrogen peroxide production carbon sphere oxygen reduction reaction

Enhanced hydrogen storage properties of MgH_(2) with the co-addition of LiBH_(4) and YNi_(5) alloy

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Journal of materials Science & Technology 2024年第11期178卷 90-99页

作者： Shaoyang Shen Wenfang Liao Zhijie Cao Jiangwen Liu Hui Wang Liuzhang Ouyang Guangdong Engineering Research center for Advanced energy Storage materials School of Materials Science and EngineeringSouth China University of TechnologyGuangzhou 510641China New energy materials Laboratory School of PhysicsNingxia UniversityYinchuan 750021China

MgH_(2),as one of the typical solid-state hydrogen storage materials,has attracted extensive ***,the slow kinetics and poor cycle stability limit its *** this work,LiBH_(4) and YNi_(5) alloy were co-added as additives to MgH_(2) via ball milling,thereby realizing an excellent dehydrogenation per-formance and good cycle stability at 300 ℃.The MgH_(2)-0.04LiBH_(4)-0.01YNi_(5) composite can release 7 wt.%of hydrogen in around 10 min at 300 ℃ and still have a reversible hydrogen storage capacity of 6.42 wt.%after 110 cycles,with a capacity retention rate as high as 90.3%based on the second dehydrogenation *** FTIR results show that LiBH_(4) can reversibly absorb and desorb hydrogen throughout the hydrogen ab/desorption process,which contributes a portion of the reversible hydrogen storage capacity to the MgH_(2)-0.04LiBH_(4)-0.01YNi_(5) *** to the small amount of LiBH_(4) and YNi_(5),the dehydro-genation activation energy of MgH_(2) did not decrease significantly,nor did the dehydrogenation enthalpy(△H)***,the MgNi3B2 and in-situ formed YH3 during the hydrogen absorption/desorption cycles is not only beneficial to the improvement of the kinetics performance for MgH_(2) but also improves its cycle *** work provides a straightforward method for developing high reversible hydrogen capacity on Mg-based hydrogen storage materials with moderate kinetic performance.

关键词： Hydrogen storage Magnesium hydride Lithium borohydride YNi5 alloy High reversible capacity

N,N-dimethylformamide tailors solvent effect to boost Zn anode reversibility in aqueous electrolyte

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National Science Review 2022年第10期9卷 147-157页

作者： Yilin Ma Qiu Zhang Luojia Liu Yixin Li Haixia Li Zhenhua Yan Jun Chen Key Laboratory of Advanced energy materials Chemistry (Ministry of Education) Renewable Energy Conversion and Storage Center (RECAST) College of Chemistry Nankai University

Rechargeable aqueous Zn batteries are considered as promising energy-storage devices because of their high capacity,environmental friendliness and low ***,the hydrogen evolution reaction and growth of dendritic Zn in common aqueous electrolytes severely restrict the application of Zn ***,we develop a simple strategy to suppress side reactions and boost the reversibility of the Zn *** introducing 30%（volume fractions） N,N-dimethylformamide（DMF） to the 2 M Zn（CF3SO3）2-H2O electrolyte（ZHD30）,the preferential hydrogen-bonding effect between DMF and H2O effectively reduces the water activity and hinders deprotonation of the *** ZHD30 electrolyte improves the Zn plating/stripping coulombic efficiency from～95.3% to～99.4% and enhances the cycles from 65 to *** Zn-polyaniline full battery employing the ZHD30 ele ctrolyte can operate over a wide temperature range from-40℃ to+25℃ and deliver capacities of 161.6,127.4 and 65.8 mAh g-1at 25,-20 and-40℃,*** work provides insights into the role of tuning solvent effects in designing low-cost and effective aqueous electrolytes.

关键词： aqueous electrolyte Zn reversibility hydrogen bond solvent effect rechargeable Zn battery