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Dual synergetic catalytic effects boost hydrogen electric oxidation performance of Pd/W_(18)O_(49)

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Nano Research 2021年第7期14卷 2441-2450页

作者： Lingxin Peng Han Tian Xiangzhi Cui Liang Su Ge Meng Zhonghua Ma Shaowen Cao Jianlin Shi State Key Lab of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China School of Chemistry and Chemical Engineering Huazhong University of Science and Technology(HUST)Wuhan 430074China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials&College of Materials Science and Engineering Donghua UniversityShanghai 201620China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

Developing anode catalysts of substantially enhanced activity for hydrogen oxidation reaction(HOR)and anti-CO poisoning performance is of great importance for the application of proton exchange membrane fuel cells(PEMFCs).Herein,we report Pd cluster in situ decorated urchin-like W_(18)O_(49)(WO_(2.72))electrocatalysts by a photo-reduction method for high performance *** synthesized Pd-WO_(2.72)-L composite of low loading amount of 0.44 wt.%Pd by Xenon light reduction exhibits markedly high HOR catalytic activity and stability in 0.5 M H_(2)SO_(4),and the specific HOR current density and mass activity of Pd-WO_(2.72)-L are~1.5 and~80 times those of 20 wt.%Pt/C catalyst,***,excellent anti-CO poisoning ability has also been *** excellent HOR activity and anti-CO poisoning performance of Pd-WO_(2.72)-L have been discussed mainly in terms of the dual synergetic catalytic effects between Pd and WO_(2.72):Pd activation to Pd^(δ+)by the electron transfer from Pd to W promotes the hydrogen adsorption and activation to H*species,which results in largely elevated HOR activity;Pd degradation due to the CO poisoning is effectively prevented by WO_(2.72),which is responsible for the excellent CO-tolerance performance.

关键词： hydrogen oxygen reaction tungsten oxide photo-reduction method synergistic effect CO tolerance catalyst

The Combined Sol-Gel and Ascorbic Acid Reduction Strategy Enabling Ba2Co2Fe12O22 Hexaferrite/Graphene Composite with Enhanced Microwave Absorption Ability

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SSRN 2023年

作者： He, Yu Wang, Ruoqi Wu, Xiaohan Tang, Chuanhao Qian, Jun Zuo, Peiyuan Zhuang, Qixin Liu, Xing Key Laboratory of Special Functional Polymeric Materials and Related Technology Ministry of Education School of Materials Science and Engineering East China University of Science and Technology Shanghai200237 China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing School of Materials Science and Engineering Wuhan University of Technology Wuhan430070 China

Graphene featuring low density and high specific surface area, is highly suitable for loading ferrite nanoparticles. However, the current efficient reducing graphene method in fabricating ferrite/graphene composites require high temperatures/pressures, ae well as highly toxic and explosive reducing agents. We herein propose a strategy for synthesizing Ba2Co2Fe12O22 hexaferrite/graphene composite MAMs by mildly reducing graphene oxide using ascorbic acid. This method enables the reduced graphene oxide with comparable C/O ratios and conductivity comparing to that achieved by other reduction methods. The proper mass ratio of graphene oxide to ferrite particles (1:2) and optimized electromagnetic parameters endow the microwave absorbing materials with a minimum reflection loss value of approximately -45.25 dB and an effective bandwidth of around 4.75 GHz. The simulation calculations are further investigated to verify the practical application of this absorber. Accordingly, it is reasonable to conclude this study provides a new synthetic approach on advanced ferrite/graphene composite based MAMs. © 2023, The Authors. All rights reserved.

关键词： Iron compounds

Simulation Analysis of Thermal Insulation Performance of Diesel Engine Piston Based on Peo and La2zr2o7 Thermal Barrier Coating

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SSRN 2024年

作者： Du, Yuxuan Fei, Chunguang Qian, Zuoqin Zhu, Siwei Shu, Zihao Zhou, Kai School of Naval Architecture Ocean and Energy Power Engineering Wuhan University of Technology Wuhan430063 China State Key Lab of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan430070 China

Traditional TBCs often suffer from limitations like consistently high surface temperatures and a delayed response to sudden variations in cylinder temperatures, which adversely impact engine efficiency. To overcome these challenges, plasma electrolytic oxidation (PEO) technology was employed to engineer TBCs with the sought-after 'thermal swing' feature. Comparative simulations were conducted to assess the thermal characteristics of PEO coatings on pistons, in contrast to standard La2Zr2O7 coatings. The PEO coatings exhibited a markedly quicker and more robust response to cylinder temperature fluctuations. This indicates that PEO coatings are highly effective in adapting swiftly to temperature changes, thereby contributing to enhanced engine performance. Additionally, the PEO coating demonstrated a notable reduction in the end temperature (TE), which is crucial for mitigating the heating effect on intake gas, in comparison to La2Zr2O7 coatings with equivalent thermal insulation properties. However, it was observed that this advantage significantly decreased when the PEO coating thickness surpassed 0.3mm. Drawing from these observations, it is concluded that PEO coatings hold several thermal advantages over La2Zr2O7 coatings, particularly in terms of thermal load management and responsiveness to in-cylinder temperature shifts. These benefits are most pronounced when the PEO coating maintains a thickness below 0.3mm. © 2024, The Authors. All rights reserved.

关键词： Lanthanum compounds

Microstructure,Mechanical,and Thermal Properties of B4C-TiB2-SiC Composites Prepared by Reactive Hot-pressing

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Journal of Wuhan University of technology(materials Science) 2020年第6期35卷 1031-1037页

作者： CAO Yaoqin HE Qianglong WANG Weimin China Helicopter Research and Development Institute Tianjin 300450China The State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

B4C-TiB2-SiC composites with excellent properties were prepared by reactive hot-pressing using B4C,TiC,and Si powders as the raw *** phase transition process was investigated by heating the powder mixture to different temperatures and combined with XRD ***2 and SiC phases were synthesized through an in situ reaction,and the mechanical and thermal properties were improved *** and mechanical properties were also studied,and the 60wt% B4C-21.6wt% TiB2-18.4wt% SiC composite showed a relative density of 99.1%,Vickers hardness of 34.6 GPa,flexural strength of 582 MPa,and fracture toughness of 5.08 MPa·m1/*** addition,the values of thermal conductivity and thermal expansion coefficient were investigated,respectively.

关键词： B4C-TiB2-SiC reactive hot pressing microstructures mechanical properties thermal properties

Bromine-Defect Induced High Sensitivity of Cs4PbBr6 Nanocrystals Humidity Sensor

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SSRN 2024年

作者： Liu, Yueli Guo, Hongbing Mei, Aohan Chen, Keqiang Chen, Wen State Key Laboratory of Silicate Materials for Architectures School of Materials Science and Engineering Wuhan University of Technology Wuhan430070 China Sanya Science and Education Innovation Park Wuhan University of Technology Sanya572024 China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing School of Materials Science and Engineering Wuhan University of Technology Wuhan430070 China Faculty of Materials Science and Chemistry China University of Geosciences Wuhan430074 China

Recently, all-inorganic halide perovskite materials have attracted much attention in the fields of humidity sensor due to their sensitive surface, tunable bandgap, high conductivity and excellent carrier mobility. However, their inherent instability and limited sensitivity restrict further application in electronic devices. Herein, we demonstrate a high-performance impedimetric humidity sensor based on an all-inorganic halide perovskite Cs4PbBr6 nanocrystals (NCs), which are obtained by anti-solvent method without long chain ligands. It is found that Br vacancy defects act as the active site to enhance the ability of adsorbing water molecules. The humidity sensor of Cs4PbBr6 NCs achieves high response value over 4 orders of magnitude at 11-98% relative humidity, short response/recovery time (8 s/6 s), favorable repeatability, excellent selectivity and good long-term stability. Moreover, high humidity sensing performance enables the humidity sensor of Cs4PbBr6 NCs to possess great potentials in breath monitor and noncontact switch application. © 2024, The Authors. All rights reserved.

关键词： Bromine compounds

Bromine-Defect Induced High Sensitivity of Cs4pbbr6 Nanocrystals Humidity Sensor

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SSRN 2024年

关键词： Bromine compounds

Guest ions pre-intercalation strategy of manganese-oxides for supercapacitor and battery applications

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Journal of Energy Chemistry 2021年第9期30卷 480-493页

作者： Lina Chen Chongyang Hao Yamin Zhang Youri Wei Linna Dai Jun Cheng Hongqiang Zhang Lijie Ci State Key Lab of Advanced Welding and Joining School of Materials Science and EngineeringHarbin Institute of Technology(Shenzhen)Shenzhen 518055GuangdongChina Key Laboratory for Liquid-Solid Structural Evolution&Processing of Materials(Ministry of Education) School of Materials Science and EngineeringShandong UniversityJinan 250061ShandongChina

Optimization of intrinsic structure of electrode materials plays decisive roles in promoting the development of energy storage systems to meet the fast-growing requirements in the *** engineering has been proved to be an effective way to obtain adequate active sites,preferable ion diffusion channels and stable structure,thus enhance the performance of *** in-depth understanding of the correlation among synthesis,structure and performance will significantly promote the development of excellent materials and energy storage ***,in this review,recent advances in regards to cation preintercalation engineering in Mn-based electrode materials for rechargeable metal ion batteries are systematically *** guest cations can expand interlayer space to promote ion diffusion kinetics,serve as pillars to stabilize structure,control composition and valence to switch electrochemical behavior,thus improve the overall performance of secondary ***,the existing challenges and perspectives are provided for the interlayer engineering and its promotion to battery industry.

关键词： Interlayer engineering Electrode materials Energy storage devices

Compressive strain in Cu catalysts:Enhancing generation of C_(2+) products in electrochemical CO_(2) reduction

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Science Bulletin 2024年第18期69卷 2881-2891页

作者： Qikui Fan Pengxu Yan Fuzhu Liu Zhongshuang Xu Pengfei Liang Xi Cao Chenliang Ye Moxuan Liu Lingyi Zhao Shan Ren Huanran Miao Xiai Zhang Zhimao Yang Xiangdong Ding Jian Yang Chuncai Kong Yuen Wu MOE Key Laboratory for Non-Equilibrium Synthesis and Modulation of Condensed Matter Key Laboratory for Advanced Materials and Mesoscopic Physics of Shaanxi ProvinceSchool of PhysicsXi’an Jiaotong UniversityXi’an 710049China State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China College of Chemistry and Materials Science Anhui Normal UniversityWuhu 241002China Department of Power Engineering North China Electric Power UniversityBeijing 102206China College of Chemistry and Chemical Engineering Xi’an University of Science and TechnologyXi’an 710054China Center for Materials and Interfaces Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Hefei National Laboratory for Physical Sciences at the Microscale Collaborative Innovation Center of Chemistry for Energy Materials(iChEM)School of Chemistry and Materials Scienceand National Synchrotron Radiation LaboratoryUniversity of Science and Technology of ChinaHefei 230026China

Elastic strain in Cu catalysts enhances their selectivity for the electrochemical CO_(2)reduction reaction(eCO_(2)RR),particularly toward the formation of multicarbon(C_(2+))***,the reasons for this selectivity and the effect of catalyst precursors have not yet been ***,we employed a redox strategy to induce strain on the surface of Cu *** transformation was employed to convert Cu nanocrystals to CuxO nanocrystals;these were subsequently electrochemically reduced to form Cu catalysts,while maintaining their compressive *** a flow cell configuration,a current density of 1 A/cm^(2)and Faradaic efficiency exceeding 80%were realized for the C_(2+)*** selectivity ratio of C_(2+)/C1 was also remarkable at 9.9,surpassing that observed for the Cu catalyst under tensile strain by approximately 7.6 ***-situ Raman and infrared spectroscopy revealed a decrease in the coverage of K+ion-hydrated water(K·H_(2)O)on the compressively strained Cu catalysts,consistent with molecular dynamics simulations and density functional theory *** element method simulations confirmed that reducing the coverage of coordinated K·H_(2)O water increased the probability of intermediate reactants interacting with the surface,thereby promoting efficient C–C coupling and enhancing the yield of C_(2+)*** findings provide valuable insights into targeted design strategies for Cu catalysts used in the eCO_(2)RR.

关键词： Strain effect CO_(2)electroreduction to C_(2+) Catalytic selectivity Copper catalyst Water coverage

Polyoxometalated metal-organic framework superstructure for stable water oxidation

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Science (New York, N.Y.) 2025年第6745期388卷 430-436页

作者： Yue, Kaihang Lu, Ruihu Gao, Mingbin Song, Fei Dai, Yao Xia, Chenfeng Mei, Bingbao Dong, Hongliang Qi, Ruijuan Zhang, Daliang Zhang, Jiangwei Wang, Ziyun Huang, Fuqiang Xia, Bao Yu Yan, Ya State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai China School of Chemistry and Chemical Engineering State Key Laboratory of Materials Processing and Die & Mould Technology Key Laboratory of Material Chemistry for Energy Conversion and Storage (Ministry of Education) Hubei Key Laboratory of Material Chemistry and Service Failure Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology (HUST) Wuhan China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences Beijing China School of Chemical Sciences University of Auckland Auckland New Zealand National Engineering Laboratory for Methanol to Olefins Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian China Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai Synchrotron Radiation Facility Shanghai China Center for High Pressure Science and Technology Advanced Research Shanghai China Key Laboratory of Polar Materials and Devices (MOE) Department of Electronics East China Normal University Shanghai China Multiscale Porous Materials Center Institute of Advanced Interdisciplinary Studies and School of Chemistry and Chemical Engineering Chongqing University Chongqing China College of Energy Material and Chemistry Inner Mongolia Key Laboratory of Low Carbon Catalysis Inner Mongolia University Hohhot China State Key Lab of Metal Matrix Composites School of Materials Science and Engineering Shanghai Jiao Tong University Shanghai China Center for Next-Generation Energy Materials and School of Chemical Engineering Sungkyunkwan University (SKKU) Seobu-ro Jangan-guGyeonggi-do Suwon South Korea

Stable, nonprecious catalysts are vital for large-scale alkaline water electrolysis. Here, we report a grafted superstructure, MOF@POM, formed by self-assembling a metal-organic framework (MOF) with polyoxometalate (POM). In situ electrochemical transformation converts MOF into active metal (oxy)hydroxides to produce a catalyst with a low overpotential of 178 millivolts at 10 milliamperes per square centimeter in alkaline electrolyte. An anion exchange membrane water electrolyzer incorporating this catalyst achieves 3 amperes per square centimeter at 1.78 volts at 80°C and stable operation at 2 amperes per square centimeter for 5140 hours at room temperature. In situ electrochemical spectroscopy and theoretical studies reveal that the synergistic interactions between metal atoms create a fast electron-transfer channel from catalytic iron and cobalt sites, nickel, and tungsten in the polyoxometalate to the electrode, stabilizing the metal sites and preventing dissolution.

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