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Application of X-ray absorption spectroscopy in carbon-supported electrocatalysts

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Nano Research 2023年第11期16卷 12438-12452页

作者： Beibei Sheng Yongheng Chu Dengfeng Cao yujian xia Chongjing Liu Shuangming Chen Li Song National Synchrotron Radiation Laboratory CAS Center for Excellence in NanoscienceUniversity of Science and Technology of ChinaHefei 230026China

Breakthroughs in energy storage and conversion devices depend heavily on the exploration of low-cost and high-performance ***-supported electrocatalysts with dimensional varieties have recently attracted significant attention due to their strong structural flexibility and easy ***,understanding the connection between their electronic,structural properties,and catalytic performance must remain a top *** radiation(SR)X-ray absorption spectroscopy(XAS)techniques,including hard XAS and soft XAS,are recognized as efficient and comprehensive platforms for probing the surface,interface,and bulk electronic structure of elements of interest in the materials *** the past decade,the flourishing development of materials science and advanced characterization technologies have led to a deeper understanding at different temporal,longitudinal,and spatial *** this review,we briefly describe the concept of XAS techniques and summarize their recent progress in addressing scientific questions on carbon-supported electrocatalysts through the development of advanced instruments and experimental *** then discuss the remaining challenges and potential research directions in nextgeneration materials frontiers,and suggest challenges and perspectives for shedding light on the structure–activity relationship.

关键词： synchrotron radiation hard X-ray absorption spectroscopy(XAS) soft XAS carbon-supported electrocatalysts

The evolution of local structure of Mo6S8 during Li+ electrochemical storage studied by in-situ tender X-ray absorption spectroscopy

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Progress in Natural Science:Materials International 2022年第6期32卷 739-744页

作者： Pengfei Yu yujian xia Xuefei Feng Shun Zheng Guoxi Ren Nian Zhang xiaosong Liu Cheng Chen xiangxin Guo State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences National Synchrotron Radiation Laboratory University of Science and Technology of China University of Chinese Academy of Sciences Tianmu Lake Institute of Advanced Energy Storage Technologies School of Physical Science and Technology Shanghai Tech University Shanghai BYD Co. Ltd. College of Physics Qingdao University

Chevrel phase Mo6S8has attracted great interest because of its capability to accommodate different types of small cations through reversible topotactic redox ***,the intercalation mechanism of Mo6S8is still far from being fully understood owing to the complexity of the crystal structure and limitation of the probe *** our study,the reaction mechanism of Li+intercalation into Mo6S8was studied as a model by in-situ tender X-ray absorption spectroscopy(itXAS) in the viewpoint of local *** to the isobestic points of the 1st derivative,the discharge process is divided into five regions while the charge process is divided into four regions,where most of the regions are assigned to the two-phase transition *** intensity change of the two spectroscopic features of the 1st derivative is found to be correlated,implying that the intercluster bond length directly affects the localization of the unoccupied states of the intracluster *** asymmetric evolution of the intensity of a’ and b’ as well as the asymmetric partition of reaction regions demonstrate the asymmetry of the reaction path in discharge and charge *** results help to clarify the remaining debates on the phase ***,itXAS is demonstrated to be a powerful tool to study the reaction mechanism of *** is complementary to NMR,XRD and so on.

关键词： Chevrel phases Cathode materials X-ray absorption In-situ measurement Local structure

Motivating Ru-bri site of RuO_(2)by boron doping toward high performance acidic and neutral oxygen evolution

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Nano Research 2022年第8期15卷 7008-7015页

作者： Chongjing Liu Beibei Sheng Quan Zhou Dengfeng Cao Honghe Ding Shuangming Chen Pengjun Zhang yujian xia xiaojun Wu Li Song National Synchrotron Radiation Laboratory CAS Center for Excellence in NanoscienceUniversity of Science and Technology of ChinaHefei 230029China Institute of Energy Hefei Comprehensive Nation Science CenterHefei 230031China Hefei National Laboratory for Physical Sciences at the Microscales Department of Materials Sciences and EngineeringUniversity of Science and Technology of ChinaHefei 230026China

The electrocatalysis of oxygen evolution reaction(OER)plays a key role in clean energy storage and ***,the sluggish kinetics and poor durability under acidic and neutral conditions severely hinder practical applications such as electrolyzer compatible with the powerful proton exchange membrane and biohybrid fuel ***,we report a borondoped ruthenium dioxide electrocatalyst(B-RuO_(2))fabricated by a facile boric acid assisted strategy which demonstrates excellent acidic and neutral OER *** functional theory calculations and advanced characterizations reveal that the boron species form an anomalous B–O covalent bonding with the oxygen atoms of RuO_(2)and expose the fully coordinately bridge ruthenium site(Ru-bri site),which seems like a switch that turns on the inactive Ru-bri site into OER-active,resulting in more exposed active sites,modified electronic structure,and optimized binding energy of ***,the B-RuO_(2)exhibits an ultralow overpotential of 200 mV at 10 mA/cm^(2)and maintains excellent stability compared to commercial RuO_(2)in 0.5 M sulfuric ***,the superior performance is as well displayed in neutral electrolyte,surpassing most previously reported catalysts.

关键词： acidic and neutral oxygen evolution reaction RuO_(2) boron doping the fully coordinately bridge ruthenium site(Ru-bri site) density functional theory

Support induced phase engineering toward superior electrocatalyst

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Nano Research 2022年第3期15卷 1831-1837页

作者： Beibei Sheng Dengfeng Cao Hongwei Shou Oyawale Adetunji Moses Wenjie Xu yujian xia Yuzhu Zhou Huijuan Wang Ping Wan Shuang Zhu Wangsheng Chu xiaojun Wu Shuangming Chen Li Song National Synchrotron Radiation Laboratory CAS Center for Excellence in NanoscienceUniversity of Science and Technology of ChinaHefei 230026China Hefei National Laboratory for Physical Sciences at the Microscales Department of Materials Sciences and EngineeringUniversity of Science and Technology of ChinaHefei 230026China Experimental Center of Engineering and Material Science University of Science and Technology of ChinaHefei 230026China Materials Interfaces Center Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 440305China Institute of Energy Hefei Comprehensive Nation Science CenterHefei 230031China

The phase transformation of catalysts has been extensively observed in heterogeneous catalytic reactions that hinder the long cycling catalysis,and it remains a big challenge to precisely control the active phase during the complex conditions in electrochemical ***,we theoretically predict that carbon-based support could achieve the phase engineering regulation of catalysts by suppressing specific phase *** single-walled carbon nanotube(SWCNT)as typical support,combined with calculated E-pH(Pourbaix)diagram and advanced synchrotron-based characterizations technologies prove there are two different active phases source from cobalt selenide which demonstrate that the feasibility of using support effect regulating the potential advantageous ***,it is worth noting that the phase engineering derived Co_(3)O_(4)-SWCNT exhibits a low overpotential of 201 mV for delivering the current density of 10 mA/cm^(2)in electrocatalytic oxygen evolution reaction(OER).Also,it reaches a record current density of 529 mA/cm^(2)at 1.63 V(***)in the electrocatalytic urea oxidation reaction(UOR),overwhelming most previously reported catalysts.

关键词： phase engineering support synchrotron radiation characterization oxygen evolution reaction(OER) urea oxidation reaction(UOR)

Interface regulation of Cu_(2)Se via Cu–Se–C bonding for superior lithium-ion batteries

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Nano Research 2023年第2期16卷 2421-2427页

作者： Kefu Zhu Shiqiang Wei Quan Zhou Shuangming Chen Yunxiang Lin Pengjun Zhang Yuyang Cao Changda Wang Yixiu Wang yujian xia Dengfeng Cao Zeinab Mohamed Xin Guo Xiya Yang xiaojun Wu Li Song National Synchrotron Radiation Laboratory Chinese Academy of Sciences(CAS)Center for Excellence in NanoscienceUniversity of Science and Technology of ChinaHefei 230029China Institutes of Physical Science and Information Technology Anhui UniversityHefei 230601China School of Chemistry and Material Sciences University of Science and Technology of ChinaHefei 230026China

Transition metal selenides have aroused great attention in recent years due to their high theoretical ***,the huge volume fluctuation generated by conversion reaction during the charge/discharge process results in the significant electrochemical performance ***,the carbon-regulated copper(I)selenide(Cu_(2)Se@C)is designed to significantly promote the interface stability and ion diffusion for selenide *** systematic X-ray spectroscopies characterizations and density functional theory(DFT)simulations reveal that the Cu–Se–C bonding forming on the surface of Cu2Se not only improves the electronic conductivity of Cu_(2)Se@C but also retards the volume change during electrochemical cycling,playing a pivotal role in interface ***,the storage kinetics of Cu_(2)Se@C is mainly controlled by the capacitance process diverting from the ion diffusion-controlled process of *** employed this distinctive Cu_(2)Se@C as anode active material in Li coin cell configuration,the ultrahigh specific capacity of 810.3 mA·h·g^(−1)at 0.1 A·g^(−1)and the capacity retention of 83%after 1,500 cycles at 5 A·g^(−1)is achieved,implying the best Cu-based Li^(+)-storage capacity reported so *** strategy of heterojunction combined with chemical bonding regulation opens up a potential way for the development of advanced electrodes for battery storage systems.

关键词： Cu–Se–C bonding interface regulation lithium-ion battery X-ray absorption spectroscopy(XAS) operando synchrotron radiation X-ray diffraction(SRXRD)

Advanced Ni-Nx-C single-site catalysts for CO2 electroreduction to CO based on hierarchical carbon nanocages and S-doping

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Nano Research 2020年第10期13卷 2777-2783页

作者： Yiqun Chen Yuejian Yao yujian xia Kun Mao Gongao Tang Qiang Wu Lijun Yang Xizhang Wang Xuhui Sun Zheng Hu Key Laboratory of Mesoscopic Chemistry of MOE and Jiangsu Provincial Lab for Nanotechnology School of Chemistry and Chemical Engineering Nanjing UniversityNanjing 210023China Soochow University-Western University Centre for Synchrotron Radiation ResearchInstitute of Functional Nano and Soft Material(FUNSOM)Soochow UniversitySuzhou 215123China

Metal-nitrogen-carbon materials are promising catalysts for CO2 electroreduction to CO. Herein, by taking the unique hierarchical carbon nanocages as the support, an advanced nickel-nitrogen-carbon single-site catalyst is conveniently prepared by pyrolyzing the mixture of NiCl2 and phenanthroline, which exhibits a Faradaic efficiency plateau of > 87% in a wide potential window of −0.6 – −1.0 V. Further S-doping by adding KSCN into the precursor much enhances the CO specific current density by 68%, up to 37.5 A·g−1 at −0.8 V, along with an improved CO Faradaic efficiency plateau of > 90%. Such an enhancement can be ascribed to the facilitated CO pathway and suppressed hydrogen evolution from thermodynamic viewpoint as well as the increased electroactive surface area and improved charge transfer fromkinetic viewpoint due to the S-doping. This study demonstrates a simple and effective approach to advanced electrocatalysts by synergetic modification of the porous carbon-based support and electronic structure of the active sites.

关键词： CO2 electroreduction single-site catalysts nickel-nitrogen-carbon S-doping hierarchical carbon nanocages

Unraveling the role of Ti3C2 MXene underlayer for enhanced photoelectrochemical water oxidation of hematite photoanodes

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Journal of Energy Chemistry 2021年第7期30卷 147-154,I0005页

作者： Haiyan Ji Shan Shao Guotao Yuan Cheng Lu Kun Feng yujian xia xiaoxin Lv Jun Zhong Hui Xu Jiujun Deng School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina Institute for Energy Research Jiangsu UniversityZhenjiang 212013JiangsuChina Institute of Functional Nano and Soft Materials Laboratory(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials&DevicesSoochow UniversitySuzhou 215123JiangsuChina Automotive Engineering Research Institute Jiangsu UniversityZhenjiang 212013JiangsuChina

Hematite is regarded as a promising photoanode for photoelectrochemical(PEC) water ***,the charge recombination occurred at the interface of FTO/hematite strictly limits the PEC performance of ***,we reported a Ti3C2 MXene underlayer modified hematite(Ti-Fe2O3) photoanode via a simple drop-casting followed by hydrothermal and annealing *** to the bifunctional role of Ti3C2 MXene underlayer in improving the interfacial properties of FTO/hematite and providing Ti source for the construction of Fe2 TiO5/Fe2O3 heterostructure in hematite nanostructure,the bulk and interfacial charge transfer dynamics of hematite are significantly enhanced,and consequently enhancing the PEC *** with the pristine hematite,the as-prepared Ti-Fe2O3 photoanode shows an increased photocurrent density from 0.80 mA/cm^(2) to 1.30 mA/cm^(2) at 1.23 V ***,a further promoted PEC performance including a dramatically increased photocurrent density of 2.49 mA/cm^(2) at1.23 V *** and an obviously lowered onset potential is achieved for the Ti-Fe2O3 sample after the subsequent surface F-treatment and the loading of FeNiOOH *** results suggest that the introduction of Ti3C2 MXene underlayer is a facile but effective approach to improve the PEC water splitting activity of hematite.

关键词： Hematite Photoelectrochemical Water splitting Ti3C2 MXene Underlayer

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监控视频异常检测与质量诊断

计算机应用与软件 2016年第6期33卷 163-167,211页

作者：夏裕建孙涵南京航空航天大学计算机科学与技术学院江苏南京210016

监控视频可能会出现一系列影响视频质量的异常情况,如清晰度、亮度异常或者视频画面存在噪声、偏色、画面冻结、水波纹、以及水平杂波等故障的情况。针对这些情况,提出监控视频异常检测与质量诊断算法。算法分析上述各种异常情况,利用... 详细信息

监控视频可能会出现一系列影响视频质量的异常情况,如清晰度、亮度异常或者视频画面存在噪声、偏色、画面冻结、水波纹、以及水平杂波等故障的情况。针对这些情况,提出监控视频异常检测与质量诊断算法。算法分析上述各种异常情况,利用图像的灰度统计信息、梯度信息,结合图像的中值滤波和帧间差异分析,完成相应的异常检测与质量诊断。实验结果表明,该方法可以有效地对监控视频进行异常检测与质量诊断。

关键词：异常检测质量诊断灰度统计信息梯度信息中值滤波帧间差异

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储能系统多电池簇健康状态均衡控制策略

中国电力 2024年第6期57卷 45-52页

作者：彭昊罗正经夏向阳曾刚欧宇健陈贵全王继军刘立洪湖南经研电力设计有限公司湖南长沙410007 长沙理工大学电气与信息工程学院湖南长沙410114

针对储能系统中多电池簇健康状态均衡问题,提出储能系统多电池簇健康状态均衡控制策略,该策略依据电池寿命变化规律和并网要求设置储能变流器并网功率下限,基于该下限确定系统参与运行的储能变流器台数,再结合层次分析法对参与运行的各... 详细信息

针对储能系统中多电池簇健康状态均衡问题,提出储能系统多电池簇健康状态均衡控制策略,该策略依据电池寿命变化规律和并网要求设置储能变流器并网功率下限,基于该下限确定系统参与运行的储能变流器台数,再结合层次分析法对参与运行的各电池簇健康状态进行量化评价,求得各储能变流器承担并网功率指令的权重系数和相应的功率大小,调整参与运行的储能变流器台数和传输功率以确保各储能变流器功率不越限。将所提控制策略与均摊控制策略相比,结果表明,所提策略可有效均衡各电池簇健康状态,延长储能电站整体使用寿命40.6%,有效提高了储能电站的安全性和经济性。

关键词：储能系统电池寿命变化规律储能变流器层次分析法安全性经济性

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