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Ultra-High Mass-Loading Cathode for Aqueous Zinc-Ion Battery Based on Graphene-Wrapped Aluminum Vanadate Nanobelts

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Nano-Micro Letters 2019年第4期11卷 215-226页

作者： Wenyu Zhang Shuquan Liang Guozhao Fang Yongqiang Yang Jiang Zhou School of Materials Science and Engineering Central South UniversityChangsha 410083HunanPeople’s Republic of China Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan Province Central South UniversityChangsha 410083HunanPeople’s Republic of China

Rechargeable aqueous zinc-ion batteries(AZIBs)have their unique advantages of cost efficiency,high safety,and environmental friendliness.However,challenges facing the cathode materials include whether they can remain chemically stable in aqueous electrolyte and provide a robust structure for the storage of Zn2+.Here,we report on H11Al2V6O23.2@graphene(HAVO@G)with exceptionally large layer spacing of(001)plane(13.36?).The graphene-wrapped structure can keep the structure stable during discharge/charge process,thereby promoting the inhibition of the dissolution of elements in the aqueous electrolyte.While used as cathode for AZIBs,HAVO@G electrode delivers ideal rate performance(reversible capacity of 305.4,276.6,230.0,201.7,180.6 mAh g?1 at current densities between 1 and 10 A g?1).Remarkably,the electrode exhibits excellent and stable cycling stability even at a high loading mass of^15.7 mg cm?2,with an ideal reversible capacity of 131.7 mAh g?1 after 400 cycles at 2 A g?1.

关键词： Aluminum Vanadate Graphene Cathode High mass loading Aqueous zinc-ion battery

A High-Capacity Ammonium Vanadate Cathode for Zinc-Ion Battery

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Nano-Micro Letters 2020年第5期12卷 153-164页

作者： Qifei Li Xianhong Rui Dong Chen Yuezhan Feng Ni Xiao Liyong Gan Qi Zhang Yan Yu Shaoming Huang Guangzhou Key Laboratory of Low-Dimensional Materials and Energy Storage Devices School of Materials and EnergyGuangdong University of TechnologyGuangzhou 510006People’s Republic of China Hefei National Laboratory for Physical Sciences at the Microscale Department of Materials Science and EngineeringCAS Key Laboratory of Materials for Energy ConversionUniversity of Science and Technology of ChinaHefei 230026People’s Republic of China Key Laboratory of Materials Processing and Mold(Zhengzhou University) Ministry of EducationZhengzhou UniversityZhengzhou 450002People’s Republic of China Aviation Fuel Research and Development Center China National Aviation Fuel Group LimitedBeijing 102603People’s Republic of China Department Institute for Structure and Function and of Physics Chongqing UniversityChongqing 400030People’s Republic of China Dalian National Laboratory for Clean Energy(DNL) Chinese Academy of SciencesDalian 116023LiaoningPeople’s Republic of China State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei 230026People’s Republic of China

Given the advantages of being abundant in resources,environmental benign and highly safe,rechargeable zinc-ion batteries(ZIBs)enter the global spotlight for their potential utilization in large-scale energy storage.Despite their preliminary success,zinc-ion storage that is able to deliver capacity>400 mAh g^-1 remains a great challenge.Here,we demonstrate the viability of NH4V4O10(NVO)as high-capacity cathode that breaks through the bottleneck of ZIBs in limited capacity.The first-principles calculations reveal that layered NVO is a good host to provide fast Zn^2+ions diffusion channel along its[010]direction in the interlayer space.On the other hand,to further enhance Zn^2+ion intercalation kinetics and long-term cycling stability,a three-dimensional(3D)flower-like architecture that is self-assembled by NVO nanobelts(3D-NVO)is rationally designed and fabricated through a microwave-assisted hydrothermal method.As a result,such 3D-NVO cathode possesses high capacity(485 mAh g^-1)and superior long-term cycling performance(3000 times)at 10 A g^-1(~50 s to full discharge/charge).Additionally,based on the excellent 3D-NVO cathode,a quasi-solid-state ZIB with capacity of 378 mAh g^-1is developed.

关键词： Zinc-ion battery Ammonium Vanadate NH4V4O10

A kinetic model for the effects of Vanadate on human erythrocyte membrane

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Science China Chemistry 1999年第5期42卷 543-551页

作者：张天蓝王夔 Department of Bioinorganic Chemistry and Inorganic Pharmaceutical Chemistry Beijing Medical University Beijing China National Research Laboratories of Natural and Biomimetic Drugs Beijing Medical University Beijing China

The effects of Vanadate on human erythrocyte membrane have been investigated with stopped-flow and equilibrium fluorescence quenching techniques. The equilibrium study showed a half-quenching concentration (K1/2) of 0.27 mmol·L-1. The stopped-flow experiment exhibited a fast rise (t1、2f～1s) and a slow drop (t1/2s 1～2 min) in fluorescence. Based on the results and that from the across membrane transport of Vanadate, a kinetic model is proposed which suggests that the membrane proteins experience a series of conformational changes before and during the quenching of the intrinsic fluorescence. These changes are induced mainly by three kinds of interactions: （i） the long-distance, non-specific interaction between the Vanadate and the erythrocyte membrane surface, （ⅱ） the charge interaction between the Vanadate and parts of the membrane proteins, and（ⅲ） the binding of the Vanadate to some membrane proteins.

关键词： Vanadate human erythrocyte membrane membrane protein lipid bilayer stopped-flow.

Doublely-doped Mg-Al-Ce-V_(2)O_(7)^(4-)LDH composite film on magnesium alloy AZ31 for anticorrosion

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Journal of Materials Science & Technology 2021年第5期64卷 66-72页

作者： Liang Wu Xingxing Ding Zhicheng Zheng Aitao Tang Gen Zhang Andrej Atrens Fusheng Pan College of Materials Science and Engineering Chongqing UniversityChongqing400044China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing400044China School of Mechanical and Mining Engineering The University of QueenslandBrisbaneQld4072Australia

A doublely-doped layered double hydroxide(LDH)film was produced on an anodized magnesium alloy AZ31.The Ce-doped Mg-Al LDH film was prepared by in-situ hydrothermal treatment method,and the intercalation of Vanadate was realized by ion-exchange reaction.The structure,morphology and composition of as-prepared LDH film were investigated by X-ray diffractometer,field-emission scanning electronic microscope and energy dispersive spectrometry.Results indicated that a uniform and compact LDH film was formed and the intercalation of Ce^(3+)and Vanadate would change the crystal structure of LDHs.The results of the potentiodynamic polarization,electrochemical impedance spectra,hydrogen evolution and corrosion weight loss tests showed the Ce^(3+)and Vanadate anions significantly improve the impedance of LDH film,and the active double-doped LDH film could effectively protect the magnesium substrate from corrosion.

关键词： Magnesium alloy Doublely-doped LDH film Vanadate Cerium Anticorrosion

MgAl-V_(2)O_7 ^(4-)LDHs/(PEI/MXene)_(10) composite film for magnesium alloy corrosion protection

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Journal of Materials Science & Technology 2021年第32期91卷 28-39页

作者： Yulong Wu Liang Wu Mikhail L.Zheludkevich Yanning Chen Maria Serdechnova Wenhui Yao Carsten Blawert Andrej Atrens Fusheng Pan State Key Laboratory of Mechanical Transmission College of Materials Science and EngineeringChongqing UniversityChongqing 400044China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China Institute of Surface Science Helmholtz-Zentrum HereonMax-Planck Str.121502 GeesthachtGermany School of Mechanical and Mining Engineering The University of QueenslandBrisbaneQld 4072Australia

In this study,MgAl-V_(2) O_7^(4-) LDHs/(poly(ethyleneimine)(PEI)/MXene)_n composite films were synthesized via(ⅰ) in-situ hydrothermal growth of Mg-AL layered double hydroxides(LDHs) on AZ31 alloy followed by Vanadate intercalation reactions,and(ⅱ) the as-prepared MgAL-V_(2) O7^(4-) LDHs film was covered by layerby-layer assembly using(PEI/MXene)_n,where n=5,10,and 20.Film characterization revealed that the outer layers(PEI/MXene) were assembled on the surface by electrostatic interaction and provided a good coverage of LDHs nanosheets.But,microcracks appeared gradually on the surface and destroyed the film integrity with increasing number of PEI/MXene layers.The corrosion tests indicated that the MgAl-V_(2) O_7^(4-)LDHs/(PEI/MXene)_(10) composite films provided a better corrosion protection ability than that of n=5 and20.The outer layers(PEI/MXene) had a corrosion inhibition protective effect on MgAl-V_(2) O_7^(4-) LDHs film.This work opened a new perspective of the MXene materials for anticorrosion application via a layer-bylayer assembly method.

关键词： Magnesium alloys Layered double hydroxides Vanadate MXene Layer-by-Layer Corrosion resistance

Alternative Nitrogenases in Anabaena variabilis: The Role of Molybdate and Vanadate in Nitrogenase Gene

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Advances in Microbiology 2013年第6期3卷 87-95页

作者： Teresa Thiel Brenda S. Pratte Department of Biology University of Missouri-St. Louis St. Louis USA

Anabaena variabilis ATCC 29413 has two distinct nitrogenases that function in heterocysts, a conventional Mo-nitrogenase and an alternative V-nitrogenase. Synthesis of these two enzymes was repressed in cells growing with a source of fixed nitrogen, such as ammonium;however, the V-nitrogenase was also repressed by Mo. Expression of the V-nitrogenase which was not affected by V and expression of the Mo-nitrogenase was not affected by the presence or absence of either Mo or V. In the absence of both Mo and V in an environment lacking fixed nitrogen, cells became starved for both metals;however, low levels of nitrogen fixation and slow growth persisted. A mutant lacking the V-nitrogenase was still able to grow very slowly in Mo-and V-free medium;however, loss of the Mo-nitrogenase in a nifDK1 mutant abolished the residual growth, suggesting that only the Mo-nitrogenase functioned under these conditions to support slow growth. The addition of Vanadate, molybdate, or tungstate, which is transported by the molybdate transporter, to cells starved for these metals resulted in an increase in nitrogenase activity within two hours after the addition of the metal and this increase required new protein synthesis. While tungstate functioned about as well as Vanadate in supporting acetylene reduction, the cells were not able to grow any better with tungstate than with no added metal. A mutant lacking the V-nitrogenase showed no increase in nitrogenase activity upon addition of tungstate, suggesting that the V-nitrogenase was able to incorporate tungstate. Tungstate was able to substitute for molybdate in repressing transcription of a Mo-transport gene, but it did not repress transcription of the vnfH gene, which was repressed by Mo. The availability of Mo and V plays an important role in controlling whether the Mo-or the V-nitrogenase is used for nitrogen fixation.

关键词： Cyanobacteria V-Nitrogenase Molybdate Vanadate Tungstate

Recent Progress in Developing Crystalline Ion Exchange Materials for the Removal of Radioactive Ions

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Chinese Journal of Structural Chemistry 2020年第12期39卷 2157-2171,2056页

作者：唐俊豪孙海燕马文冯美玲黄小荥 State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China

The nuclear fuel cycle inevitably generates a large amount of radioactive waste liquid,which will pose a serious threat to the ecological environment and human health.Ion exchange method has received wide attention for its easy operation,low cost and no secondary pollution.However,the effective removal of radioactive ions from complex solutions still remains a serious challenge due to their environmental mobility and radiotoxicity.We have developed an efficient strategy to construct crystalline ion-exchange materials by inducing layered or three-dimensional microporous anionic frameworks by organic cations that can be effectively exchanged by radioactive metal ions.This type of materials can be applied effectively to the removal of radioactive ions from complex solutions and the removal mechanism has been deeply clarified by means of single crystal structure analyses,theoretical calculations,etc.This review summarizes our recent progress in the study of synthesis,structures and properties of radioactive ion removals for such type of crystalline ion-exchange materials.

关键词： ion exchange crystalline materials metal chalcogenide Vanadate MOF organic amine radionuclide remediation

Electrical and Spectroscopic Studies of the CdO Substituted Lead Vanadate Glass System vs Crystalline Form

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New Journal of Glass and Ceramics 2012年第1期2卷 34-40页

作者： Ponnada Tejeswara Rao Kocharlakota V. Ramesh Devulapalli L. Sastry 不详

Results of the direct current (DC) Electrical Conductivity, thermoelectric power and Electron Spin Resonance (ESR) of CdO substituted PbO-V2O5 glass system are reported. Conduction in these glasses is found to be electronic and the hoping of polaron seems to be the dominant process in the transport mechanism. There is a remarkable decrease in the activation energy for conduction in the annealed and devitrified samples when compared to their amorphous counter parts. It is observed that there is remarkable improvement in the conductivity of the crystalline samples when compared to their amorphous counter parts. The thermoelectric power measurements indicates that the amorphous samples are n-type at room temperature where as the crystalline samples are p-type at room temperature. In crystalline samples the hyperfine structure is nearly smeared out and a relatively broad line with an isotropic g value characterizes the spectra.

关键词： Transport Properties-ESR Lead Vanadate Semi Conducting Glasses

Pairs of Ln(Ⅲ)dopant ions in crystalline solid luminophores:an ab initio computational study

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Journal of Rare Earths 2016年第8期34卷 820-827页

作者： A.Shyichuk G.Meinrath S.Lis Department of Rare Earths Faculty of ChemistryAdam Mickiewicz UniversityUmultowska 89b61-614 PoznafiPoland Radioactivity Environment Remediation(RER)Consultants Fuchsbauerweg 5094036 PassauGermany

Formation of dopant ions clusters in solid （glass） luminophores may affect efficiency of non-radiative energy transfer proc- esses between dopant （photoactivator） ions via shortening of the effective distance between them. This study was based on the as- sumption that the distance between the dopant ions affects the energy of crystal volume at proximity. According to this idea, semi-empirical and ab initio density functional theory （DFT） calculations were performed on various supercells of YVO4：Eu3＋ as a model system. It was noted that a shorter Eu-Eu distance resulted in lower total energy of the system, compared to an analogous structure with distant Eu3＋ ions. As lower energy configurations are preferred, the observed phenomenon was considered to be related to dopant ions clusters formation. Additionally, the values of energies obtained from DFT calculations were used to estimate the per- centage of dopant ions occurring as pairs, for different dopant concentrations. The estimation agreed quite well with the available lit- erature data.

关键词： crystalline luminophore lanthanides Vanadate DFT dopant clustering rare earths