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Green Energy & Environment 2023年第2期8卷 452-458页

作者： Yingying Yang Honglei Fan Tianbin Wu Guanying Yang Buxing Han Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Colloid and Interface and ThermodynamicsInstitute of ChemistryChinese Academy of SciencesBeijing100190China Education Research Center of Chaoyang District Beijing100021China School of Chemistry and Chemical Engineering University of Chinese Academy of SciencesBeijing100049China College of Chemistry and Chemical Engineering Yantai UniversityYantaiChina

Phenol in waste water threatens human health and is difficultly to be decomposed by nature.Efficient degradation of high-loaded phenol in water under mild condition is still a great challenge.Herein,ionic liquids with Tungstate anion were designed and prepared.It was found that dodecyltrimethylammonium Tungstate could catalyzed degradation of phenol into gases and water thoroughly at 323 k in 8 h.Tungstate anion revealed good catalytic oxidative activity and long carbon chain group connecting with cation of ionic liquids enriched phenol around catalysts,which induced the complete degradation of phenol at mild conditions.Increasing the amounts of hydrogen peroxide benefited to the total degradation of phenol.In addition,the ionic liquid could be reused for its excellent thermal stability.Our work provided a different strategy to treat waste water containing phenol efficiently.

关键词： Ionic liquid Oxidative degradation Phenol Tungstate Hydrogen peroxide

Formation of CoAl layered double hydroxide on the boehmite surface and its role in Tungstate sorption

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Journal of Environmental Sciences 2018年第3期30卷 103-115页

作者： Hyuck Hur Richard J.Reeder Department of Chemistry Stony Brook University Stony Brook NY 11794 USA Department of Geosciences Stony Brook University Stony Brook NY 11794 USA

Sorption of Tungstate on boehmite（γ-Al OOH）is increased by co-sorption with Co^（2＋）over the near-neutral p H range.Batch uptake experiments show up to a 3-fold increase in Tungstate uptake over the range WO4^（2-）=50–1000μmol/L compared to boehmite not treated with Co^（2＋）.Desorption experiments reveal a corresponding decrease in sorption reversibility for Tungstate co-sorbed with Co^（2＋）.Reaction of boehmite with Co^（2＋）results in the formation of Co Al layered double hydroxide（LDH）,as confirmed by X-ray diffraction and X-ray absorption spectroscopy.Tungsten L3-edge X-ray absorption near edge structure（XANES）reveals that W（VI）is octahedrally coordinated in all sorption samples,with polymeric Tungstate species forming at higher Tungstate concentrations.X-ray diffraction and X-ray absorption spectroscopy indicate that the mechanism for enhancement of Tungstate uptake is the formation of surface complexes on boehmite at low Tungstate concentrations,while exchange into the Co Al LDH becomes important at higher Tungstate concentrations.The results provide a basis for developing strategies to enhance Tungstate sorption and to limit its environmental mobility at near-neutral pH conditions.

关键词： Tungsten Tungstate Cobalt Boehmite （AIOOH） Layered double hydroxide Adsorption

New developments in nonlinear optical crystals of molybdate and Tungstate

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New developments in nonlinear optical crystals of molybdate ...

The growth units and hydrothermal preparation of lead Tungstate (PbWO_4) crystallites

中国化学会第九届全国无机化学学术会议

作者： Xutang Tao Zeliang Gao Youxuan Sun Xiangxin Tian Qian Wu State Key Laboratory of Crystal Materials Shandong University

A series of new nonlinear crystals based on molybdates that containing Tellurium atoms have been grown by flux method and their linear and nonlinear optical properties have been studied. Polycrystalline Ba Te Mo2O9（BTM） samples were synthesized using the traditional solid state reaction techniques. The results indicate temperatures below 570 °C favored production of β-BTM, while higher temperatures led to production of α-BTM. The phase relationship between the two phases has been studied. Since both β-BTM and α-BTM melt incongruently, appropriate fluxes should be introduced to decrease the crystal growth temperature. After a great amount of attempts, the Te O2-Mo O3 flux system was adopted to grow large crystals. The obtained crystals are shown in Fig. 1. The second order nonlinear optical properties of β-BTM were studied by means of the Marker fringe technology and the phase matching method. The values and relative signs of the second order nonlinear optical coefficients were obtained, with the largest one being d31 = 9.88 pm/V. At 1064 nm, the crystal can realize both type I and type II phase matching, and the effective nonlinear coefficient is 10.3 pm/V for phase matching II in the xoy plane.

关键词： Molybdate Tungstate phase transfer nonlinear optical

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Science China(Technological Sciences) 2000年第5期43卷 495-503页

作者：元如林施尔畏李汶军郑燕青吴南春仲维卓 Huadong Geology College Fuzhou 344000 China Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

The crystal structure of lead Tungstate (PbWO4) can be regarded as ordered combination of the tungsten oxide tetrahedrons (WO4) and lead ions (Pb2+). According to the growth unit model, the growth units of lead Tungstate are the aggregations of the tungsten oxide tetrahedrons and lead cations with various geometry configurations. It is suggested that the favorable growth units of lead Tungstate crystal are pyramidal, tetragonal prism and quadrangular units corresponding to geometric orientations of the simple forms of the crystal. Under low restricted growth conditions, the growth form of lead Tungstate crystallites is the aggregation of the geometric configurations of these favorable growth units. The above conclusions are completely confirmed by the experiment on hydrothermal preparation of lead Tungstate crystallites.

关键词： lead Tungstate crystal growth unit hydrothermal preparation.

不对称配位操纵电子再分布实现高电流密度下电催化水氧化

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Science Bulletin 2023年第13期68卷 1389-1398,M0004页

作者：赵晟胡峰尹立杰李林林彭生杰 College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China

作为目前最有前景的绿氢生产方式,电解水技术被研究者广泛关注.其中,电催化析氧反应(oxygen evolution reaction,OER)作为电解水的半反应,由于其缓慢的四电子转移步骤而成为电解水器件的能量瓶颈.高效的OER催化电极设计是解决该问题的... 详细信息

作为目前最有前景的绿氢生产方式,电解水技术被研究者广泛关注.其中,电催化析氧反应(oxygen evolution reaction,OER)作为电解水的半反应,由于其缓慢的四电子转移步骤而成为电解水器件的能量瓶颈.高效的OER催化电极设计是解决该问题的有效方式.本文分析了OER催化剂中氧原子介导的电子重排与活性位点配位不对称性之间的构效关系.通过自发氧化还原反应,将镍离子引入到泡沫镍(NF)表面的FeWO_(4)中,以此破坏FeWO_(4)晶格中FeO_(6)八面体的对称性,并基于此调节Fe位点的电子结构.结构调控促进了钨酸盐适度重构成为具有高OER活性的羟基氧化物.在碱性环境中,具有不对称配位Fe位点的Fe_(0.53)Ni_(0.47)WO_(4)/NF自支撑电极在10 mA cm^(-2)的电流密度下,可获得170 mV的超低过电势,并在1000 mA cm^(-2)的高电流密度下可维持稳定500 h.这种新型OER催化电极为高活性电催化系统的设计提供了新的见解.

关键词： Electrocatalysis Oxygenevolutionreaction Tungstate Electrodes Electron regulation

NON-ISOTHERMAL KINETIC STUDY ON THE THERMAL DEHYDRATION OF SODIUM Tungstate DIHYDRATE

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中国有色金属学会会刊：英文版 1998年第3期8卷 165-168页

作者： Liu, Shijun Chen, Qiyuan Zhang, Pingmin Central South Univ of Technology Changsha China

１ＩＮＴＲＯＤＵＣＴＩＯＮＳｏｄｉｕｍｔｕｎｇｓｔａｔｅｄｉｈｙｄｒａｔｅｉｓｕｓｅｄｉｎｔｈｅｐｒｅｐａｒａｔｉｏｎｏｆｃｏａｔｅｄｅｌｅｃｔｒｏｄｅｓｆｏｒｅｌｅｃｔｒｏｃａｔａｌｙｓｉｓ［１］ａｎｄａｓｆｉｒ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＳｏｄｉｕｍｔｕｎｇｓｔａｔｅｄｉｈｙｄｒａｔｅｉｓｕｓｅｄｉｎｔｈｅｐｒｅｐａｒａｔｉｏｎｏｆｃｏａｔｅｄｅｌｅｃｔｒｏｄｅｓｆｏｒｅｌｅｃｔｒｏｃａｔａｌｙｓｉｓ［１］ａｎｄａｓｆｉｒｅｒｅｔａｒｄａｎｔｆｏｒｆａｂｒ...

关键词： non isothermal kinetics dehydration sodium Tungstate dihydrate

Study on Synergistic Effect of Tungstate and Benzotriazole on Corrosion Inhibition of Carbon Steel in Solutions Containing Cl-

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Study on Synergistic Effect of Tungstate and Benzotriazole o...

Photoluminescence properties and thermal stability of Eu^(3+)-activated La_(7)Ta_(3)W_(4)O_(30) red-emitting phosphors for near-UV-excited w-LEDs

The 2nd China International Corrosion Control Conference (CICC’2002)

作者： LI YAN, LU ZHU Center of corrosion prevention, East University of science and technology, P. R. China, Shanghai 200237

In this paper, the corrosion inhibition behavior of Tungstate or benzotriazole (BTA) used alone and of their combination in solutions containing Cl" was studied by using electrochemical techniques. The results indicated that the inhibition efficiency of Tungstate was higher than that of BTA. The efficiency increased with increasing concentration of Tungstate or BTA. It had been found in the studies of synergistic effect of Tungstate and BTA that in pH 9.0 solution, the largest R, could been obtained in solution with the concentration ratio of Tungstate / BTA being 1:1. Lowering the pH value of solution would reduce the efficiency of inhibitors, especially in binary inhibitors. Increasing the concentration of Cl" heightened the corroding rate of carbon steel in the solutions with various inhibitors, but the influence of Cl" on corroding rate in binary inhibitors was not so strong as in single component. The results of surface analysis showed there are W, C, N, O and Fe elements in the protecting film formed in binary inhibitors. The thickness of the film was about 12-15 nm.

关键词： Tungstate Benzotriazole Synergistic Effect EIS Carbon Steel

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Journal of Rare Earths 2021年第8期39卷 905-912页

作者： Yu Ren Bin Deng Ting Liang Shuang Shu Junlan Guo Shoucheng Zhao Ruijin Yu College of Chemistry&Pharmacy Northwest A&F UniversityYangling 712100China College of Chemistry&Biology and Environmental Engineering Xiangnan UniversityChenzhou 423043China Hunan Provincial Key Laboratory o/Xiangnan Rare-Precious Metals Compounds Research and Application Xiangtan UniversityChenzhou 423043China College of Materials and Chemical Engineering Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion MaterialsChina Three Gorges UniversityYichang 443002China

Novel trivalent europium(Eu^(3+))-activated La_(7)Ta_(3)W_(4)O_(30):xEu^(3+)(x=0.5 mol%-40 mol%) red-emitting phosphors were synthesized by means of a high-temperature solid-state reaction.The structure,morphology,photoluminescence,thermal-stability properties,lifetime,and color-rendering of the prepared phosphors were investigated in detail.The La_(7)Ta_(3)W_(4)O_(30):Eu^(3+) phosphors show five emission peaks under near-ultraviolet(n-UV) at 397 nm,and these peaks are ascribed to the transitions of ^(5)D0-^(7)Fj(j=0,1,2,3 and 4) by Eu^(3+) ions.The optimal doping concentration of Eu^(3+) is 20 mol%,and the critical distance of the energy transfer between the Eu^(3+)ions was calculated to be 1.768 nm.The quenching temperature(T_(0.5)) of La_(7)Ta_(3)W_(4)O_(30):20 mol%Eu^(3+) is about 440 K.The quantum yield(QY) was measured to be 85.85%.The fabricated white-light-emitting diodes(w-LEDs) possess high color-rendering index(R_(a)) of 90,and high correlated color temperature(CCT) of 5810 K,respectively.The Commission Internationale de L’Eclairage(CIE) coordinates are(0.311,0.322).Therefore,the prepared phosphor has a promising application for w-LEDs.

关键词： Luminescence Phosphor Tungstate La_(7)Ta_(3)W_(4)O_(30) Rare earths

ELECTRODE SELECTION OF ELECTROLYSIS WITH MEMBRANE FOR SODIUM Tungstate SOLUTION

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Journal of Central South University 1999年第2期11卷 107-110页

Xiao Liansheng Wang Wei Zhang Qixiu Gong Bofan Cao Jiashu (Department of Metallurgical Science and Engineering, Central South University of Technology, Changsha 410083, China) Abstrac By measuring the electrode polarization curves of many kinds of materials and life spans of electrodes through intensifying electrolysis in the process, the appropriate electrode materials for different stages of electrolysis of sodium Tungstate solution with membrane have been selected The effects of the electrodes with different shapes on electrolysis have been investigated. The result shows that network electrode is more suitable to electrolysis of sodium Tungstate solution.

关键词： sodium Tungstate electrolysis membrane electrode

Synthesis and photoluminescence properties of Ca_3R_(2–x)WO_9:xEu^(3+)(R=Y, Gd) phosphors

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Journal of Rare Earths 2015年第2期33卷 135-139页

作者：茹晶晶秦小焕颜桂炀陈建中 Department of Chemistry Ningde Normal University School of Chemistry and Pharmaceutical Sciences Guangxi Normal Univer-sity College of Chemistry and Chemical Engineering Fuzhou University

Ca3R2–xWO9：xEu^3＋（R=Y, Gd） red-emitting phosphors were prepared by solid state reactions. These samples were characterized by differential scanning calorimetry and thermogravimetry analysis（DSC-TGA）, X-ray diffraction（XRD）, Fourier transform infrared spectroscopy（FTIR）, photoluminescence（PL） and field emission scanning electron microscopy（FE-SEM） analyses. The optimum sintering temperature for these phosphors was 1100 ℃, and the optimum sintering time was 2 h. The optimum doped concentration of Eu^3＋ in Ca3Y2–xWO9：xEu^3＋ and Ca3Gd2–xWO9：xEu^3＋ were x=1.5 and x=1.1, respectively. These phosphors could be excited by near-UV light of 394 nm and blue light of 465 nm, and showed strong red emission line at 612 nm（^5D0→^7F2）, which indicated that Ca3R2–xWO9：xEu^3＋（R=Y, Gd） were promising red candidates for white LED.

关键词： Tungstate rare earth luminescence LED