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1T-phase MoS_(2.edge-anchored Pt_(1)-S_(3)active site boosting selective hydrogenation of biomass-derived maleic anhydride

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稀有金属:英文版 2023年第8期42卷 2658-2669页

作者： Xue Sun Yi Zhao Kuan Chang Bo Peng Qing-Qing Gu Bing Yang Bai-Yang Yu Jing Xu Fu-Dong Liu Ying Zhang Cheng-Si Pan Yang Lou Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi 214122China International Joint Research Center for Photoresponsive Molecules and Materials Jiangnan UniversityWuxi 214122China SINOPEC Research Institute of Petroleum Processing Beijing 100083China Dalian National Laboratory for Clean energy Dalian Institute of Chemical PhysicsDalian 116023China school of Food Science and Technology Jiangnan UniversityWuxi 214122China Department of Civil Environmentaland Construction EngineeringCatalysis Cluster for Renewable Energy and Chemical Transformations(REACT)NanoScience Technology Center(NSTC)University of Central FloridaOrlandoFL 32816USA

Selective hydrogenation of biomass-derived maleic anhydride(MAH)to succinic anhydride(SA)is valuable but remains a challenge due to the complicated reaction *** here report that single Pt atoms decorated onto the edges of two-dimensional(2.)1Tphase MoS_(2.(Pt1/1T-MOS_(2.SAC)as a proof-of-concept catalyst can efficiently convert biomass-derived MAH to SA with 100%conversion and 100%selectivity under mild *** kinetic data and characterization results suggest that the catalytic performance of the edge-anchored Pt1/1T-MoS_(2.SAC originates from the facile H_(2.dissociation induced by the electron-deficient Pt1atoms and the pocket-like configuration of Pt1active site confines the adsorption configuration of MAH by the steric *** strategy of fabricating edge-confined catalysts offers a new direction to design novel SACs for biomass-derived transformations.

关键词： Two-dimensional(2.)1T-MoS_(2. Edgeconfinement Pt single atoms Selective hydrogenation reaction Reaction kinetics

Mechanistic understanding of the charge storage processes in FeF_(2. aggregates assembled with cylindrical nanoparticles as a cathode material for lithium-ion batteries by in situ magnetometry

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Carbon energy 2022年第6期4卷 1011-1020页

作者： Zhengqiang Hu Fengling Zhang Huanyu Liang Hao Zhang Huaizhi Wang Tiansheng Wang Renbin Liu Jie Liu Yadong Li Xiaotong Dong Lianyu Bao Zhuan Liang Yaqun Wang Shishen Yan Qiang Li Hongsen Li Center for Marine Observation and Communications College of PhysicsQingdao UniversityQingdaoShandongChina College of Electrical engineering and Automation Shandong University of Science and TechnologyQingdaoShandongChina State Key Laboratory of Crystal Materials School of PhysicsShandong UniversityJinanShandongChina

Transition metal fluorides(TMFs)cathode materials have shown extraordinary promises for electrochemical energy storage,but the understanding of their electrochemical reaction mechanisms is still a matter of debate due to the complicated and continuous changing in the battery internal ***,we design a novel iron fluoride(FeF_(2.)aggregate assembled with cylindrical nanoparticles as cathode material to build FeF_(2. lithium-ion batteries(LIBs)and employ advanced in situ magnetometry to detect their intrinsic electronic structure during cycling in real *** results show that FeF_(2. cannot be involved in complete conversion reactions when the FeF_(2. LIBs operate between the conventional voltage range of 1.0–4.0 V,and that the corresponding conversion ratio of FeF_(2. can be further ***,we first demonstrate that the spin-polarized surface capacitance exists in the FeF_(2. cathode by monitoring the magnetic responses over various voltage *** research presents an original and insightful method to examine the conversion mechanism of TMFs and significantly provides an important reference for the future artificial design of energy systems based on spinpolarized surface capacitance.

关键词： charge storage mechanism FeF_(2.cathode materials in situ magnetometry lithium-ion batteries

Cs^＋-K^＋ Exchange in Z-Cut KTiOPO4 Crystal Covered with Chromium Masking Layer

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Chinese physics Letters 2008年第6期25卷 2281-2284页

作者：张瑞锋卢霏连洁刘汉平刘祥志王亮玲王克明路庆明 school of Information Science and engineering Shandong University Jinan 250100 school of physics and Microelectronics Shandong University Jinan 250100 school of Chemistry and Chemical engineering Shandong University Jinan 250100

Cs^＋-K^＋ ion exchanges are performed on z-cut KTiOPO4 crystals with chromium coating covered. The temperature of ion exchange is 430℃, and the time range from 15min to 30min. The dark mode spectra of the samples are measured by the prism coupling method. The channel structures on the samples are observed by a microscope and the near field pattern of the channel waveguides are measured by the end-fire coupling method. The refractive index of the samples increases and the increments at surface are modulated due to the existence of Cr film. In the region covered by Cr film, the refractive index of the samples at the surface increases dramatically in a shallow layer. The results of energy dispersive x-ray spectra indicate that in the region covered with Cr film, Cr ions participate in the ion exchange process, and enhance the refractive index. The results may provide a possibility that achieves index enhancement and Cr doping synchronically.

关键词： supernova explosion proto-neutron star shock wave

Experimental investigation of electrode cycle performance and electrochemical kinetic performance under stress loading

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Chinese physics B 2021年第1期30卷 380-390页

作者： Zi-Han Liu Yi-Lan Kang Hai-Bin Song Qian Zhang Hai-Mei Xie Tianjin Key Laboratory of Modern engineering Mechanics School of Mechanical EngineeringTianjin UniversityTianjin 300350China

Lithium-ion batteries suffer from mechano–electrochemical coupling problems that directly determine the battery life. In this paper, we investigate the electrode electrochemical performance under stress conditions, where seven tensile/compressive stresses are designed and loaded on electrodes, thereby decoupling mechanics and electrochemistry through incremental stress loads. Four types of multi-group electrochemical tests under tensile/compressive stress loading and normal package loading are performed to quantitatively characterize the effects of tensile stress and compressive stress on cycle performance and the kinetic performance of a silicon composite electrode. Experiments show that a tensile stress improves the electrochemical performance of a silicon composite electrode, exhibiting increased specific capacity and capacity retention rate, reduced energy dissipation rate and impedances, enhanced reactivity, accelerated ion/electron migration and diffusion, and reduced polarization. Contrarily, a compressive stress has the opposite effect, inhibiting the electrochemical performance. The stress effect is nonlinear, and a more obvious suppression via compressive stress is observed than an enhancement via tensile stress. For example, a tensile stress of 675 k Pa increases diffusion coefficient by 32.5%, while a compressive stress reduces it by 35%. Based on the experimental results, the stress regulation mechanism is analyzed. Tensile stress loads increase the pores of the electrode material microstructure, providing more deformation spaces and ion/electron transport channels. This relieves contact compressive stress, strengthens diffusion/reaction, and reduces the degree of damage and energy dissipation. Thus, the essence of stress enhancement is that it improves and optimizes diffusion, reaction and stress in the microstructure of electrode material as well as their interactions via physical morphology.

关键词： prestress loading silicon composite electrode tensile stress enhancement compressive stress suppression

Vanadium-modified hard carbon spheres with sufficient pseudographitic domains as high-performance anode for sodium-ion batteries

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Carbon energy 2023年第2期5卷 12-23页

作者： Fuping Chen Yujie Di Qiong Su Dongming Xu Yangpu Zhang Shuang Zhou Shuquan Liang Xinxin Cao Anqiang Pan school of Material Science and engineering Central South UniversityChangshaHunanChina school of physics and Chemistry Hunan First Normal UniversityChangshaHunanChina Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan Province Central South UniversityChangshaHunanChina

Hard carbons are promising anode materials for sodium-ion *** meet practical requirements,searching for durable and conductive carbon with a stable interface is of great ***,we prepare a series of vanadiummodified hard carbon submicrospheres by using hydrothermal carbonization followed by high-temperature ***,the introduction of vanadium can facilitate the nucleation and uniform growth of carbon spheres and generate abundant V-O-C interface bonds,thus optimizing the reaction ***,the optimized hard carbon spheres modified by vanadium carbide,with sufficient pseudographitic domains,provide more active sites for Na ion migration and *** a result,the HC/VC-1300 electrode exhibits excellent Na storage performance,including a high capacity of 42. mAh g^(-1) at 50mA g^(-1) and good rate capability at 1 A g^(-1).This study proposes a new strategy for the synthesis of hard carbon spheres with high tap density and emphasizes the key role of pseudographitic structure for Na storage and interface stabilization.

关键词： anode materials hard carbon sodium-ion batteries stable interface vanadium carbide

Catalytically active atomically thin cuprate with periodic Cu single sites

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National Science Review 2023年第1期10卷 226-235页

作者： Huimin Yang Shibo Xi Na Guo Mu Wang Lingmei Liu Pin Lyu Xiaolong Yu Jing Li Haomin Xu Xiao Hai Zejun Li Xinzhe Li Tao Sun Xiaoxu Zhao Yu Han Wei Yu Jie Wu Chun Zhang Honghan Fei Ming Joo Koh Jiong Lu Department of Chemistry National University of Singapore Institute of Chemical and engineering Sciences Department of physics National University of Singapore Advanced Membranes and Porous Materials Center King Abdullah University of Science and Technology SDU-ANU Joint Science College Shandong University school of Materials Science and engineering Peking University Centre for Advanced 2. Materials and Graphene Research Centre National University of Singapore Department of Chemistry Tongji University

Rational design and synthesis of catalytically active two-dimensional(2.) materials with an abundance of atomically precise active sites in their basal planes remains a great ***,we report a ligand exchange strategy to exfoliate bulk [Cu4(OH)6] [O3S(CH2.4SO3] cuprate crystals into atomically thin 2. cuprate layers([Cu2.OH)3]+).The basal plane of 2. cuprate layers contains periodic arrays of accessible unsaturated Cu(Ⅱ) single sites(2.-CuSSs),which are found to promote efficient oxidative Chan-Lam *** me chanistic studies reveal that the reactions proceed via coordinatively unsaturated CuO4(Ⅰ) single sites with the formation of Cu(Ⅰ) species in the rate-limiting step,as corroborated by both operando experimental and theoretical *** robust stability of 2.-CuSSs in both batch and continuous flow reactions,coupled with their recyclability and good performance in complex molecule derivatization,render 2.-CuSSs attractive catalyst candidates for broad utility in fine chemical synthesis.

关键词： exfoliation nanosheet heterogeneous catalysis

Transverse momentum balance and angular distribution of bb dijets in Pb+Pb collisions

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Chinese physics C 2020年第10期44卷 129-136页

作者： Wei Dai Sa Wang Shan-Liang Zhang Ben-Wei Zhang Enke Wang school of Mathematics and physics China University of GeosciencesWuhan 430074China Key Laboratory of Quark&Lepton physics(MOE)and Institute of Particle physics Central China Normal UniversityWuhan 430079China Guangdong Provincial Key Laboratory of nuclear Science Institute of Quantum MatterSouth China Normal UniversityGuangzhou 510006China

In this study,the production of inclusive b-jet and bb dijets in Pb+Pb collisions has been investigated byconsidering the in-medium evolution of heavy and light quarks *** initial hard processes of inclusiveb-jet and bb production are described using a next-to-leading order(NLO)plus parton shower Monte Carlo(MC)event generator,SHERPA,which can be well matched with the experimental data in p+p *** uses the Langevin transport model to describe the evolution of the bottom ***,the collisionalenergy loss and higher-twist description are considered to determine the radiative energy loss from both thebottom and light *** compare the theoretical simulation of the inclusive jet and b-jet RAA in the Pb+Pb collisionsat√SNN=2.76 TeV with the experimental data and present the theoretical simulation of the momentum balanceof the bb dijet in the Pb+Pb collisions at 5.02.TeV along with recent CMS data for the first time.A similartrend to that seen in inclusive dijets is observed in bb dijets;the distribution of the production shifts to smaller xJ owingto the jet quenching ***,we report the prediction of the normalized azimuthal angle distribution of the bb dijet in the Pb+Pb collisions at 5.02.*** medium-induced energy loss effect of the bb dijets will generallysuppress its production;however,the same side(ΔФ→0 region)suffers more energy loss than the far side(ΔФ→πregion),thus leading to suppression on the same side and enhancement on the far side in the normalized azimuthalangle distribution in A+A collisions.

关键词： heavy quark jet heavy ion energy loss

Efficient oxidation of ethylbenzene catalyzed by cobalt zeolitic imidazolate framework ZIF-67 and NHPI

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Journal of energy Chemistry 2014年第6期23卷 742-746页

作者： Hongyan Li Hong Ma Xinhong Wang Jin Gao Chen Chen Song Shi Minjie Qu Na Feng Jie Xu school of Textile and Material engineering Dalian Polytechnic University State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian National Laboratory for Clean Energy

Efficient catalytic oxidation of ethylbenzene to acetophenone was realized using the catalytic system of cobalt zeolitic imidazolate framework ZIF-67/N-hydroxyphthalimide （NHPI） under mild conditions. 95.2. conversion of ethylbenzene with 90.3% selectivity to acetophenone could be obtained at 373 K under 0.3 MPa 02.for 9 h. The results show that there exists synergetic effect between ZIF-67 and NHPI. 1-Phenylethyl hydroperoxide （PEHP） was generated via a radical process involving the hydrogen abstraction from ethylbenzene by phthalimide N-oxyl, and subsequently effectively decomposed to acetophenone by ZIF-67.

关键词： N-hydroxyphthalimide Z1F-67 oxidation ethylbenzene acetophenone

Electronic and Spectroscopic Properties of La2.C112.Isomers

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Chemical Research in Chinese Universities 2018年第2期34卷 241-246页

作者： WANG Mingqian WANG Boning LI Weiqi ZHOU Xin YANG Li TIAN Weiquan Key Laboratory of Critical Materials Technology for New energy Conversion and Storage Ministry of Industry and Information School of Chemistry and Chemical Engineering Harbin Institute of Technology Harbin 150080 P. R. China Department of physics Harbin Institute of Technology Harbin 150001 P. R. China College of Chemistry and Chemical engineering Chongqing University Chongqing 401331 P. R. China

Among the 3352.isolated pentagon rule（IPR） isomers and 12.073 non-IPR isomers satisfying adjacent pentagon pairs（APPs）≤2.of fullerene C112. the lowest-energy IPR and non-IPR isomers of C112.and C112.6- have been fully screened by the density functional tight-binding（DFTB） and density functional theory（DFT） methods for stu- dying the electronic and spectroscopic properties of La2.C112. The structural features and infrared and absorption spectra of those isomers were analyzed in detail, and the characteristic fingerprint absorption peaks were assigned. To clarify the relative stabilities of La2.C112.isomers at high temperature, entropy contributions were determined at the B3LYP level. IPR isomer La2.C112.C2.860136） is not the lowest-energy isomer but is one of the most important isomers. This is the first work that considers non-IPR C112.isomers when exploring the structure and properties of La2.C112.

关键词： C112.fullerene La-endohedral metallofullerene(La-EMF) Thermostability IR spectnan UV-Vis spectrum