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锆/铪氧簇中硫原子导向的金属-配体协同高效催化胺氧化反应

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science Bulletin 2024年第4期69卷 492-501页

作者：孙胜男牛倩林焦敏何莉玲石景文黄青刘江兰亚乾 school of chemistry South China Normal UniversityGuangzhou 510006China College of materials science and engineering Nanjing Forestry UniversityNanjing 210037China school of chemistry and materials science Nanjing Normal UniversityNanjing 210023China

The performance applications(e.g.,photocatalysis)of zirconium(Zr)and hafnium(Hf)based complexes are greatly hindered by the limited development of their structures and the relatively inert metal reactivity.In this work,we constructed two ultrastable Zr/Hf-based clusters(Zr_(9)-TC4A and Hf_(9)-TC4A)using hydrophobic 4-tert-butylthiacalix[4]arene(H4TC4A)ligands,in which unsaturated coordinated sulfur(S)atoms on the TC4A^(4-)ligand can generate strong metal–ligand synergy with nearby active metal Zr/Hf sites.As a result,these two functionalized H4TC4A ligands modified Zr/Hf-oxo clusters,as catalysts for the amine oxidation reaction,exhibited excellent catalytic activity,achieving very high substrate conversion(>99%)and product selectivity(>90%).Combining comparative experiments and theoretical calculations,we found that these Zr/Hf-based cluster catalysts accomplish efficient amine oxidation reactions through synergistic effect between metals and ligands:(i)The photocatalytic benzylamine(BA)oxidation reaction was achieved by the synergistic effect of the dual active sites,in which,the naked S sites on the TC4A^(4-)ligand oxidize the BA by photogenerated hole and oxygen molecules are reduced by photogenerated electrons on the metal active sites;(ii)in the aniline oxidation reaction,aniline was adsorbed by the bare S sites on ligands to be closer to metal active sites and then oxidized by the oxygen-containing radicals activated by the metal sites,thus completing the catalytic reaction under the synergistic catalytic effect of the proximity metal–ligand.In this work,the Zr/Hf-based complexes applied in the oxidation of organic amines have been realized using active S atom-directed metal–ligand synergistic catalysis and have demonstrated very high reactivity.

关键词： Zirconium/hafnium-oxo clusters Amine oxidation reaction Photocatalytic reaction Synergistic catalysis

Calibration of local chemical pressure by optical probe

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National science Review 2023年第9期10卷 258-269页

作者： Xiao Zhou Mei-Huan Zhao Shan-Ming Yao Hongliang Dong Yonggang Wang Bin Chen Xianran Xing Man-Rong Li Key Laboratory of Bioinorganic and Synthetic chemistry of Ministry of Education School of ChemistrySun Yat-sen University Center for High Pressure science and Technology Advanced Research school of materials science and engineering Peking University Beijing Advanced Innovation Center for materials Genome engineering Institute of Solid State Chemistry University of Science and Technology Beijing school of science Hainan University

Chemical stabilization of a high-pressure metastable state is a major challenge for the development of advanced materials.Although chemical pressure(Pchem) can effectively simulate the effect of physical pressure(Pphy)) experimental calibration of the pressure passed to local structural motifs,denoted as local chemical pressure(Pchem-△) which significantly governs the function of solid materials,remains absent due to the challenge of probing techniques.Here we establish an innovative methodology to experimentally calibrate the Pchem-△and build a bridge between Pchemand Pphyvia an optical probe strategy.Site-selective Bi3+-traced REVO4(RE=Y,Gd) is adopted as a prototype to introduce Bi3+optical probes and on-site sense of the Pchem-△experienced by the REO8motif.The cell compression of RE0.9gBi0.02VO4under Pphyis chemically simulated by smaller-ion substitution(Sc3+→RE3+) in RE0.98-xScxBi0.02VO4.The consistent red shift(△λ) of the emission spectra of Bi3+,which is dominated by locally pressure-induced REO8dodecahedral variation in RE0.98Bi0.02VO4(Pphy) and RE0.98-xScxBi0.02VO4(Pchem-△),respectively,is evidence of their similar pressure-dependent local structure evolution.This innovative △λ-based experimental calibration of Pchem-△in the crystal-field dimension portrays the anisotropic transmission of Pchemto the local structure and builds a bridge between Pchem-△and Pphyto guide a new perspective for affordable and practical interception of metastable states.

关键词： chemical pressure high pressure ion substitution optical parameter spectra shift pressure calibration

Efficient utilization of glass fiber separator for low-cost sodium-ion batteries

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矿物冶金与材料学报:英文版 2023年第10期30卷 1878-1886页

作者： Xiaohang Ma Zhijie Chen Tianwen Zhang Xueqian Zhang Yuan Ma Yanqing Guo Yiyong Wei Mengyuan Ge Zhiguo Hou Zhenfa Zi school of Physics and materials engineering Hefei Normal UniversityHefei 230601China school of chemistry and materials science University of Science and Technology of ChinaHefei 230026China

The separator is a key component of sodium-ion battery,which greatly affects the electrochemical performances and safety characteristics of the battery.Conventional glass fiber separator cannot meet the requirements of large-scale application because of high cost and poor mechanical properties.Herein,the novel composite separators are prepared by a simple slurry sieving process using glass fiber separator scraps and ordinary qualitative filter paper as raw materials.As the composite mass ratio is 1:1,the composite separator has excellent comprehensive properties,including tensile strength of 15.8 MPa,porosity of 74.3%,ionic conductivity of 1.57×10^(-3)S·cm^(-1)and thermal stability at 210℃.The assembled sodium-ion battery shows superior cycling performance(capacity retention of 94.1%after 500 cycles at 1C)and rate capacity(retention rate of 87.3%at 10C),and it maintains fine interface stability.The above results provide some new ideas for the separator design of high-performance and low-cost sodium-ion batteries.

关键词： separator glass fiber low cost sodium-ion batteries

Electrochemical urea synthesis by co-reduction of CO_(2) and nitrate with Fe^(Ⅱ)-Fe^(Ⅲ)OOH@BiVO_(4) heterostructures

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Journal of Energy chemistry 2023年第9期84卷 385-393页

作者： Hua-Qing Yin Zuo-Shu Sun Qiu-Ping Zhao Lu-Lu Yang Tong-Bu Lu Zhi-Ming Zhang Institute for New Energy materials&Low Carbon Technologies School of Chemistry and Chemical EngineeringSchool of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China

Traditional urea synthesis under harsh conditions is usually associated with high energy input and has aroused severe environmental concerns.Electrocatalytic C-N coupling by converting nitrate and CO_(2) into urea under ambient conditions represents a promising alternative process.But it was still limited by the strong competition between nitrate electrochemical reduction(NO_(3)ER) and CO_(2) electrochemical reduction(CO_(2)ER).Here,Fe^(Ⅱ)-Fe~ⅢOOH@BiVO_(4)-n heterostructures are constructed through hydrothermal synthesis and exhibited superior performance toward urea electrosynthesis with NO_(3)~-and CO_(2) as feedstocks.The optimized urea yield and Faradaic efficiency over Fe^(Ⅱ)-Fe~ⅢOOH@BiVO_(4)-2 can reach13.8 mmol h^(-1) g^(-1) and 11.5% at-0.8 V vs.reversible hydrogen electrode,which is much higher than that of bare FeOOH(3.2 mmol h^(-1) g^(-1) and 1.3%),pristine BiVO_(4)(2.0 mmol h^(-1) g^(-1) and 5.4%),and the other Fe^(Ⅱ)-Fe~ⅢOOH@BiVO_(4)-n(n=1,3,5) heterostructures.Systematic experiments have verified that BiVO_(4)and FeOOH are subreaction active sites towards simultaneous CO_(2)ER and NO_(3)ER,respectively,achieving co-activation of CO_(2) and NO_(3)~-on Fe^(Ⅱ)-Fe~ⅢOOH@BiVO_(4)-2.Moreover,the urea synthesis via the ^(*)CO and NO*intermediates and C-N coupling was confirmed by the in situ Fourier transform infrared spectroscopy.This work not only alleviates the CO_(2) emission and nitrate pollution but also presents an efficient catalyst for synergistic catalysis towards sustainable urea synthesis.

关键词： Electrocatalysis Urea synthesis CO_(2)reduction Nitrate conversion

Anchoring Active Sites by Pt_(2)FeNi Alloy Nanoparticles on NiFe Layered Double Hydroxides for Efficient Electrocatalytic Oxygen Evolution Reaction

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Energy & Environmental materials 2022年第1期5卷 270-277页

作者： Zhicheng Zheng Yanru Guo Hao Wan Gen Chen Ning Zhang Wei Ma Xiaohe Liu Shuquan Liang Renzhi Ma school of materials science and engineering Central South University College of chemistry and Molecular engineering Peking University school of Chemical engineering Zhengzhou University International Center for materials Nanoarchitectonics (WPI-MANA) National Institute for Materials Science (NIMS)

Strategy of anchoring alloy nanoparticles made up of the efficient catalytic element(e.g.,Ni,Fe)on dodecyl sulfate(DS^(-))-intercalated NiFe layered double hydroxides(DS^(-)-NiFe LDH)obtained by a convenient one-step hydrothermal coprecipitation method for essentially enhancing oxygen evolution reaction(OER)performance was proposed.The results of structural characterization indicate Pt_(2)FeNi alloy nanoparticles evenly distribute on the surface of DS^(-)-NiFe LDH.The sizes of the Pt_(2)FeNi nanoparticles,closely related to their OER performance,could be wellcontrolled by adjusting the amount of H;PtCl;addition.The composite structure of as-prepared product was stable during processes of synthesis,exfoliation,self-assembly,and subsequent electrocatalytic OER.Rigorous electrochemical test proving the contributing catalytic active sites was located at the interface between Pt_(2)FeNi and DS^(-)-NiFe LDH,and the Ni and Fe were the major active elements while O atoms are adsorption sites.The formation of Pt_(2)FeNi nanoparticles could greatly prompt the reduction of Tafel slope.The best-performing Pt_(2)FeNi/DS^(-)-NiFe LDH with a Pt content of 0.98 wt%achieved low overpotential of 204 mV at 10 mA cm^(-2)and 262 mV at 50 mA cm^(-2).This work provides a convenient and effective strategy to create additional active sites for enhancing OER performance of NiFe LDH and make contribution to its wide application.

关键词： electrocatalysis NiFe Layered double hydroxides oxygen evolution reaction Pt_(2)FeNi nanoparticles

Study on hydrogen adsorption on WO_(3)(001) surface by density functional theory calculation

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钨科技(英文) 2023年第4期5卷 558-569页

作者： Ping-Guo Jiang Xiang-Biao Yu Yi-Yu Xiao Su Zhao Wang-Jun Peng school of materials science and engineering Shanghai Dianji UniversityShanghai200240China school of Metallurgy and chemistry engineering Jiangxi University of Science and TechnologyGanzhou341000China

Hydrogen reduction of tungsten oxide is currently the most widely used technology to produce metal tungsten for its simplicity and pollution-free nature.The computer simulation is a powerful tool for exploring the mechanism of hydrogen reduction of tungsten oxide from a microscopic view.The density functional theory(DFT) is applied to investigate the adsorption characteristic of hydrogen molecule on the surface and inside the lattice of WO_(3).The adsorption energy of hydrogen on the WO_(3)(001) surface is 66.56 kJ.mol^(-1) which is larger than the adsorption energy of hydrogen molecule inside the lattice of WO3 which indicates that once the hydrogen diffuses inside the lattice,it is easier to adsorb on the O atom to break W-O bond.And The diffusion process of a hydrogen molecule from the WO-terminated WO_(3)(001) surface to the inside of the WO_(3) lattice and hydrogen molecule adsorption inside the lattice was investigated.The activation energy of hydrogen molecule diffusion from the surface down to the first interstitial and diffusion from the first interstitial down to the second interstitial is 195.41 and 172.81 kJ·mol^(-1),respectively.The controlling step of hydrogen reduction of tungsten oxide may be the hydrogen molecule diffusion inside the oxides lattice through the interstitial.

关键词： WO_(3) Hydrogen reduction DFT

硫掺杂氮化碳纳米片棒状聚集体用于光催化析氢

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science China materials 2023年第12期66卷 4669-4679页

作者：林斯颖吴宝刚李琪肖旭东郑芒刘佳男谢颖蒋保江 school of chemistry and materials science Heilongjiang UniversityHarbin 150080China College of materials science and Chemical engineering Harbin Engineering UniversityHarbin 150001China

合成具有较宽吸收光谱的少层氮化碳是一个具有吸引力的课题.杂原子掺杂(特别是硫掺杂)可以有效地避免纳米级片层氮化碳中由于量子限制效应所引起的带隙加宽.与二次煅烧硫化不同的是,预硫化超分子前驱体可以原位地形成硫掺杂氮化碳纳米... 详细信息

合成具有较宽吸收光谱的少层氮化碳是一个具有吸引力的课题.杂原子掺杂(特别是硫掺杂)可以有效地避免纳米级片层氮化碳中由于量子限制效应所引起的带隙加宽.与二次煅烧硫化不同的是,预硫化超分子前驱体可以原位地形成硫掺杂氮化碳纳米片堆叠聚集体(SCN).这种少层的框架结构呈现出了更大的比表面积(139.06 m^(2)g^(−1)),暴露了更多的活性位点.此外,硫的引入使原七嗪环的共轭结构发生扭曲,从而通过激活价带电子的n→π*跃迁而缩小带隙.在模拟日光条件下,SCN0.8(3925.8μmol g^(−1)h^(−1))的析氢速率是块体氮化碳(BCN,485.2μmol g^(−1)h^(−1))的8.1倍.本工作旨在最大限度地利用杂原子掺杂和形态调控的协同效应来提高光催化活性,且为光催化剂的多维同步优化提供了新的视角.

关键词： sulfur-doped carbon nitride few-layer supramolecular self-assembly photocatalysis hydrogen evolution

Highly stable aqueous phase black phosphorus quantum dots with enhanced fluorescence property

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Journal of materials science & Technology 2022年第21期116卷 50-57页

作者： Yingli Ma Xiaoguang Xu Xiaoshuang Zhang Mayifei Rong Liying Lu Yan Li Wenhao Dai Hongwu Du Yong Jiang school of materials science and engineering University of Science and Technology BeijingBeijing 100083China school of chemistry and Biological engineering University of Science and Technology BeijingBeijing 100083China

Black phosphorus quantum dots(BPQDs)are a kind of outstanding optical material due to the tunable band structure.However,their fluorescence property and stability are obviously weakened in the aqueous phase,which extremely restricts the development of BPQDs.Here,we propose a new method to prepare stable BPQDs in an aqueous solution directly with high absolute fluorescence quantum yield.Aqueous phase BPQDs are synthesized by liquid exfoliation and hydrothermal with NH_(2)-polyethylene glycol(PEG)-NH_(2) as the modification agent to protect the BPQDs,which have high stability more than six months.In addition,NH_(2)-PEG-NH_(2) is also a surface passivation agent to enhance the emission of BPQDs by forming P-N bonds,which is confirmed by an absolute fluorescent quantum yield of 11.5%.Moreover,BPQDs show excellent resistance to a strong acid environment and high ionic strengths except for Fe^(3+).Therefore,the BPQDs are a kind of highly selective and linear response fluorescence probe for Fe^(3+).Considering the good biocompatibility of BPQDs,they are employed as cell fluorescent label probes and show excellent fluorescence imaging contrast.Based on the unique structural stability and fluorescence performance in the aqueous phase,BPQDs are potential candidates for Fe^(3+)detection and optical bio-imaging.

关键词： Black phosphorus Quantum dots Fluorescence Iron detection Cell imaging

Microstructure and wear behavior of Mo–60Si–5B coating doped with 0.5 at% La by spark plasma sintering

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Progress in Natural science:materials International 2022年第6期32卷 752-757页

作者： Zilong Wu Kanglu Feng Jiangbo Sha Chungen Zhou school of materials science and engineering Beihang University

Mo-60Si-5B coating doped with 0.5 at% La was prepared on niobium silicon based alloy by spark plasma sintering.The microstructure and wear behavior of the 0.5La-Mo-60Si-5B(0.5La-MSB) coating were investigated.The results show that the mean grain sizes of the Mo-60Si-5B(0La-MSB) and 0.5La-MSB coatings are calculated to be 3.27 μm and 2.85 μm,respectively.The addition of La plays a role of refining the grains of 0.5La-MSB coating.The specific wear rate of 0.5La-MSB coating is decreased by up to 26.8% at the oscillation frequency of 20 Hz and the sliding load of 11 N compared to 0La-MSB coating.The anti-friction performance of Mo-60Si-5B coating is modified by the addition of 0.5 at.% La.The improvement of anti-friction performance of the Mo-60Si-5B coating is due to the increased hardness and the provided lubrication function by La2O3.

关键词： Metal coatings La 2 O 3 Nanoindentation Wear behavior