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Synthesis of a new salt containing polyoxometallate anion and M-Cu-S cluster cation [MS_4Cu_4(γ-MePy)_8][M_6O_19] (M = Mo,W).Crystal structure of [WS_4Cu_4(γ-MePy)_8][W_6O_19] 被引量:2
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作者 POPE, Michael T. Department of Chemistry, Georgetown University, Washington DC S0057, U.S.A.LANG, Jian-PingDepartment of Chemistry, Suzhou University, Suzhou, Jiangsu 215006, ChinaXIN, Xin-Quan Coordination Chemistry Institute, Nanjing University, Nanjing, Jiangsu S1000S, ChinaYU, Kai-BeiChengdu Center of Analysis and Measurement, Chinese Academy of Sciences, Chengdu, Sichuan 610041, China 《Chinese Journal of Chemistry》 SCIE CAS CSCD 1995年第1期40-46,共7页
Reactions of (NH4)2MS4, AgBr and CuBr in r-methylpyridine produced one new compound, [MS4Cu4(r-MePy)8]M6O19] (1, M = W; 2, M = Mo), of which 1 was characterized by single crystal X-ray analysis. The crystal data: orth... Reactions of (NH4)2MS4, AgBr and CuBr in r-methylpyridine produced one new compound, [MS4Cu4(r-MePy)8]M6O19] (1, M = W; 2, M = Mo), of which 1 was characterized by single crystal X-ray analysis. The crystal data: orthorhombic, Pbcn, a = 15.434(4),b= 16.732(2), c = 28.657(7) A, V = 7400.8(8) A3, Z = 4, R = 0.072 for 3121 independent data. The compound is the first example which contains both polyoxotnngstate anion and heteropolynuclear cluster cation. In the structure of the cation four edges of the tetrahedral WS42- core are coordinated by four copper atoms, giving a WS4Cu4 aggregate of approximate D2h symmetry. The differences between the reaction of Cu+ with MS42- and that of Ag+ with MS42- in pyridine and its derivatives are discussed. 展开更多
关键词 Mo(W)-Cu-S cluster cation polyoxometallate anion crystal structure.
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A Simple Polyoxometallate for Selective Oxidation of Benzyl Alcohol to Benzaldehyde with Hydrogen Peroxide 被引量:1
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作者 Tian,Wei Hou,Yang +3 位作者 Wang,Xiaoguang Lu,Bin Zhao,Jingxiang Cai,Qinghai 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2012年第2期433-437,共5页
A series of Keggin-type polyoxometallates, M3(PW12O40)2 [M = Ni, Zn, Co, Mn, Cu], FePW12O40, Ni3(PMo12O40)2 and Ni2SiWl2040, were prepared and used as catalysts for selective oxidation of benzyl alcohol into benza... A series of Keggin-type polyoxometallates, M3(PW12O40)2 [M = Ni, Zn, Co, Mn, Cu], FePW12O40, Ni3(PMo12O40)2 and Ni2SiWl2040, were prepared and used as catalysts for selective oxidation of benzyl alcohol into benzaldehyde with H202 as an oxidant under solvent-free condition. Ni3(PW12040)2·26H2O afforded high catalytic activity with TON of 550.6 mol/(mol cat.) and 87.3% selectivity. However, this catalyst can be easily recovered and reused. 展开更多
关键词 benzyl alcohol BENZALDEHYDE polyoxometallateS hydrogen peroxide
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Understanding Bonding Nature of α-Keggin Polyoxometalates[XW_(12)O_(40)]^(n−)(X=Al,Si,P,S):A Generalized Superatomic Perspective
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作者 Rui Li Yulei Shi +4 位作者 Famin Yu Rui Wang Haitao Yan Boon K.Teo Zhigang Wang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第6期176-183,共8页
α-Keggin polyoxometalates(POMs)[XW_(12)O_(40)]^(n−)(X=Al,Si,P,S)are widely used in batteries owing to their remarkable redox activity.However,the mechanism underlying the applications appears inconsistent with the wi... α-Keggin polyoxometalates(POMs)[XW_(12)O_(40)]^(n−)(X=Al,Si,P,S)are widely used in batteries owing to their remarkable redox activity.However,the mechanism underlying the applications appears inconsistent with the widely accepted covalent bonding nature.Here,first-principles calculations show that XW_(12)are core–shell structures composed of a shell and an XO_(4)^(n−)core,both are stabilized by covalent interactions.Interestingly,owing to the presence of a substantial number of electrons in W_(12)O_(36)shell,the frontier molecular orbitals of XW_(12)are not only strongly delocalized but also exhibit superatomic properties with high-angular momentum electrons that do not conform to the Jellium model.Detailed analysis indicates that energetically high lying filled molecular orbitals(MOs)have reached unusually high-angular momentum characterized by quantum number K or higher,allowing for the accommodation of numerous electrons.This attribute confers strong electron acceptor ability and redox activity to XW_(12).Moreover,electrons added to XW_(12)still occupy the K orbitals and will not cause rearrangement of the MOs,thereby maintaining the stability of these structures.Our findings highlight the structure–activity relationship and provide a direction for tailor-made POMs with specific properties at atomic level. 展开更多
关键词 first principles molecular orbital POLYOXOMETALATE redox activity superatom
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Heterostructured Pt-Ni_(3)Mo_(3)N formed via ammonia-containing polyoxometalates for highly efficient electrocatalytic hydrogen evolution in acid medium
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作者 Bianqing Ren Xue Gong +5 位作者 Jing Cao Dezheng Zhang Zizhun Wang Ping Song Ce Han Weilin Xu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期698-704,共7页
Constructing heterostructured nanohybrid is considered as a prominent route to fabricate alternative electrocatalysts to commercial Pt/C for hydrogen evolution reaction(HER).In this work,(NH_(4))_(4)[NiH_(6)Mo_(6)O_(4... Constructing heterostructured nanohybrid is considered as a prominent route to fabricate alternative electrocatalysts to commercial Pt/C for hydrogen evolution reaction(HER).In this work,(NH_(4))_(4)[NiH_(6)Mo_(6)O_(4)]·5H_(2)O polyoxometalates(NiMo_(6))are adopted as the cluster precursors for simple fabrication of heterostructured Pt-Ni_(3)Mo_(3)N nanohybrids supported by carbon black(Pt-Ni_(3)Mo_(3)N/C)without using additional N sources.The improved porosity and enhanced electronic interaction of Pt-Ni_(3)Mo_(3)N/C should be attributed to the integration of Pt with NiMo_(6),which favors the mass transport,promotes the formation of exposed catalytic sites,and benefits the regulation of intrinsic activity.Thus,the as-obtained Pt-Ni_(3)Mo_(3)N/C exhibits impressive and durable HER performance as indicated by the low overpotential of 13.7 mV at the current density of 10 mA cm^(-2) and the stable overpotential during continuous working at 100 mA cm^(-2) for 100 h.This work provides significant insights for the synthesis of new highly active heterostructured electrocatalysts for renewable energy devices. 展开更多
关键词 POLYOXOMETALATES Cluster precursors Heterostructured nanohybrids Hydrogen evolution reaction ELECTROCATALYSIS
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Lindqvist-type Polyoxometalates Act as Anti-breast Cancer Drugs via Mitophagy-induced Apoptosis
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作者 Chen-guang YAO Zi-jia ZHAO +6 位作者 Ting TAN Jiang-ning YAN Zhong-wei CHEN Jun-tao XIONG Han-luo LI Yan-hong WEI Kang-hong HU 《Current Medical Science》 SCIE CAS 2024年第4期809-819,共11页
Objective Lindqvist-type polyoxometalates(POMs)exhibit potential antitumor activities.This study aimed to examine the effects of Lindqvist-type POMs against breast cancer and the underlying mechanism.Methods Using dif... Objective Lindqvist-type polyoxometalates(POMs)exhibit potential antitumor activities.This study aimed to examine the effects of Lindqvist-type POMs against breast cancer and the underlying mechanism.Methods Using different cancer cell lines,the present study evaluated the antitumor activities of POM analogues that were modified at the body skeleton based on molybdenum-vanadium-centered negative oxygen ion polycondensations with different side strains.Cell colony formation assay,autophagy detection,mitochondrial observation,qRT-PCR,Western blotting,and animal model were used to evaluate the antitumor activities of POMs against breast cancer cells and the related mechanism.Results MO-4,a Lindqvist-type POM linking a proline at its side strain,was selected for subsequent experiments due to its low half maximal inhibitory concentration in the inhibition of proliferation of breast cancer cells.It was found that MO-4 induced the apoptosis of multiple types of breast cancer cells.Mechanistically,MO-4 activated intracellular mitophagy by elevating mitochondrial reactive oxygen species(ROS)levels and resulting in apoptosis.In vivo,breast tumor growth and distant metastasis were significantly reduced following MO-4 treatment.Conclusion Collectively,the results of the present study demonstrated that the novel Lindqvist-type POM MO-4 may exhibit potential in the treatment of breast cancer. 展开更多
关键词 ANTITUMOR breast cancer POLYOXOMETALATE MITOCHONDRIA MITOPHAGY
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High-rate lithium-ion battery performance of a ternary sea urchin-shaped CoNiO_(2)@NiP_(6)Mo_(18)/CNTs composites
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作者 Li-ping Cui Shuang Sun +4 位作者 Kai Yu Shu Zhang Mei-lin Wang Jia-jia Chen Bai-bin Zhou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期516-525,共10页
Bimetallic oxides are attractive anode materials for lithium-ion batteries(LIBs)due to their large theoretical capacity.However,the low conductivity,short cycle life,and poor rate capability are the bottlenecks for th... Bimetallic oxides are attractive anode materials for lithium-ion batteries(LIBs)due to their large theoretical capacity.However,the low conductivity,short cycle life,and poor rate capability are the bottlenecks for their further applications.To overcome above issues,the basket-like polymolybdate(NiP_(6)Mo_(18))and carbon nanotubes(CNTs)were uniformly embedded on the urchin-shaped CoNiO_(2)nanospheres to yield a ternary composites CoNiO_(2)@NiP_(6)Mo_(18)/CNTs via electrostatic adsorption.The multi-level morphology of urchin spinules accelerates the diffusion rate of Li^(+);CNT improves the conductivity and enhances cycle stability of the material;and heteropoly acid contributes more redox activity centres.Thus,CoNiO_(2)@NiP_(6)Mo_(18)/CNTs as an anode of LIBs exhibits a high initial capacity(1396.7 mA h g^(−1)at 0.1 A g^(−1)),long-term cycling stability(750.2 mA h g^(−1)after 300 cycles),and rate performance(450.3 mA h g^(−1)at 2 A g^(−1)),which are superior to reported metallic oxides anode of LIBs.The density functional theory(DFT)and kinetic mechanism suggest that CoNiO_(2)@NiP_(6)Mo_(18)/CNTs delivers an outstanding pseudocapacitance and rapid Li^(+)diffusion behaviors,which is due to the rich surface area of the urchin-like CoNiO_(2)with the uniform embeddedness of NiP_(6)Mo_(18)and CNTs.This study provides a new idea for optimizing the performance of bimetallic oxides and developing high-rate lithium-ion battery composites. 展开更多
关键词 Bi-metal oxides Transition metal oxides POLYOXOMETALATES Nanocomposite LIBs
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Polyoxometalates-Modulated Hydrophilic-Hydrophobic Composite Interfacial Material for Efficient Solar Water Evaporation and Salt Harvesting in High-Salinity Brine
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作者 Sihang Cheng Cuimei Liu +3 位作者 Yingqi Li Huaqiao Tan Yonghui Wang Yangguang Li 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第3期219-227,共9页
Solar vapor generation(SVC)represents a promising technique for seawater desalination to alleviate the global water crisis and energy shortage.One of its main bottleneck problems is that the evaporation efficiency and... Solar vapor generation(SVC)represents a promising technique for seawater desalination to alleviate the global water crisis and energy shortage.One of its main bottleneck problems is that the evaporation efficiency and stability are limited by salt crystallization under high-salinity brines.Herein,we demonstrate that the 3D porous melamine-foam(MF)wrapped by a type of self-assembling composite materials based on reduced polyoxometalates(i.e.heteropoly blue,HPB),oleic acid(OA),and polypyrrole(PPy)(labeled with MF@HPB-PPy_(n)-OA)can serve as efficient and stable SVC material at high salinity.Structural characterizations of MF@HPB-PPy_(n)-OA indicate that both hydrophilic region of HPBs and hydrophobic region of OA co-exist on the surface of composite materials,optimizing the hydrophilic and hydrophobic interfaces of the SVC materials,and fully exerting its functionality for ultrahigh water-evaporation and anti-salt fouling.The optimal MF@HPB-PPy_(10)-OA operates continuously and stably for over 100 h in 10wt%brine.Furthermore,MF@HPB-PPy_(10)-OA accomplishes complete salt-water separation of 10wt%brine with 3.3kgm^(-2)h^(-1)under 1-sun irradiation,yielding salt harvesting efficiency of 96.5%,which belongs to the record high of high-salinity systems reported so far and is close to achieving zero liquid discharge.Moreover,the low cost of MF@HPB-PPy_(10)-OA(2.56$m^(-2))suggests its potential application in the practical SVC technique. 展开更多
关键词 heteropoly blue(HPB) hydrophilic-hydrophobic interface polyoxometalates(POM) salt-water separation solar vapor generation(SVG)
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Recent Advances on Polyoxometalate-Based Ion-Conducting Electrolytes for Energy-Related Devices 被引量:2
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作者 Dongming Cheng Ke Li +1 位作者 Hongying Zang Jiajia Chen 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第2期262-274,共13页
Solid-state electrolytes have attracted considerable attention in new energyrelated devices due to their high safety and broad application platform.Polyoxometalates(POMs)are a kind of molecular-level cluster compounds... Solid-state electrolytes have attracted considerable attention in new energyrelated devices due to their high safety and broad application platform.Polyoxometalates(POMs)are a kind of molecular-level cluster compounds with unique structures.In recent years,owing to their abundant physicochemical properties(including high ionic conductivity and reversible redox activity),POMs have shown great potential in becoming a new generation of solid-state electrolytes.In this review,an overview is investigated about how POMs have evolved as ion-conducting materials from basic research to novel solid-state electrolytes in energy devices.First,some expressive POM-based ion-conducting materials in recent years are introduced and classified,mainly inspecting their structural and functional relationship.After that,it is further focused on the application of these ionconducting electrolytes in the fields of proton exchange membranes,supercapacitors,and ion batteries.In addition,some properties of POMs(such as inherent dimension,capable of forming stable hydrogen bonds,and reversible bonding to water molecules)enable these functional POM-based electrolytes to be employed in innovative applications such as ion selection,humidity sensing,and smart materials.Finally,some fundamental recommendations are given on the current opportunities and challenges of POM-based ion-conducting electrolytes. 展开更多
关键词 energy devices ion conduction POLYOXOMETALATES solid-state electrolytes
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Single-Molecule Confinement Induced Intrinsic Multi-Electron Redox-Activity to Enhance Supercapacitor Performance
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作者 Su Yang Meiling Wang +8 位作者 Yong Zhang Pinyi He Wenhua Cong Chongji Wang Qiankun Yang Xuguang Liu Tian Wang Xianming Zhang Jiadong Zhou 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第4期227-238,共12页
Aggregation of polyoxometalates(POM)is largely responsible for the reduced performance of POM-based energy-storage systems.To address this challenge,here,the precise confinement of single Keggin-type POM molecule in a... Aggregation of polyoxometalates(POM)is largely responsible for the reduced performance of POM-based energy-storage systems.To address this challenge,here,the precise confinement of single Keggin-type POM molecule in a porous carbon(PC)of unimodal super-micropore(micro-PC)is realized.Such precise single-molecule confinement enables sufficient activity center exposure and maximum electron-transfer from micro-PC to POM,which well stabilizes the electron-accepting molecules and thoroughly activates its inherent multi-electron redox-activity.In particular,the redox-activities and electron-accepting properties of the confined POM molecule are revealed to be super-micropore pore size-dependent by experiment and spectroscopy as well as theoretical calculation.Meanwhile,the molecularly dispersed POM molecules confined steadily in the“cage”of micro-PC exhibit unprecedented large-negative-potential stability and multiple-peak redox-activity at an ultra-low loading of~11.4 wt%.As a result,the fabricated solid-state supercapacitor achieves a remarkable areal capacitance,ultrahigh energy and power density of 443 mF cm^(-2),0.12 mWh cm^(-2)and 21.1 mW cm^(-2),respectively.This work establishes a novel strategy for the precise confinement of single POM molecule,providing a versatile approach to inducing the intrinsic activity of POMs for advanced energy-storage systems. 展开更多
关键词 intrinsic redox-activity POLYOXOMETALATES single-molecule confinement SUPERCAPACITOR
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Decomposition of a β-O-4 lignin model compound over solid Cs-substituted polyoxometalates in anhydrous ethanol: acidity or redox property dependence? 被引量:1
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作者 吴学众 焦文千 +4 位作者 李秉正 黎演明 张亚红 王全瑞 唐颐 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第7期1216-1228,共13页
Production o f aromatics from lignin has attracted much attention. Because of the coexistence of C-O and C-C bonds and their complex combinations in the lignin macromolecular network, a plausible roadmap for de... Production o f aromatics from lignin has attracted much attention. Because of the coexistence of C-O and C-C bonds and their complex combinations in the lignin macromolecular network, a plausible roadmap for developing a lignin catalytic decomposition process could be developed by exploring the transformation mechanisms of various model compounds. Herein, decomposition of a lignin model compound, 2-phenoxyacetophenone (2-PAP), was investigated over several ce-sium-exchanged polyoxometalate (Cs-POM) catalysts. Decomposition of 2-PAP can follow two dif-ferent mechanisms: an active hydrogen transfer mechanism or an oxonium cation mechanism. The mechanism for most reactions depends on the competition between the acidity and redox proper-ties of the catalysts. The catalysts of POMs perform the following functions: promoting active hy-drogen liberated from ethanol and causing formation of and then temporarily stabilizing oxonium cations from 2-PAP. The use of Cs-PMo, which with strong redox ability, enhances hydrogen libera-tion and promotes liberated hydrogen transfer to the reaction intermediates. As a consequence, complete conversion of 2-PAP (〉99%) with excellent selectivities to the desired products (98.6% for phenol and 91.1% for acetophenone) can be achieved. 展开更多
关键词 Lignin model compound β-O-4 ether bond POLYOXOMETALATE Hydrogen transfer mechanism Oxonium cation mechanism Anhydrous ethanol
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Amorphous TiO_2-supported Keggin-type ionic liquid catalyst catalytic oxidation of dibenzothiophene in diesel 被引量:3
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作者 Zhendong Yu Donghui Wang +6 位作者 Suhang Xun Minqiang He Ruliang Ma Wei Jiang Hongping Li Wenshuai Zhu Huaming Li 《Petroleum Science》 SCIE CAS CSCD 2018年第4期870-881,共12页
Supported ionic liquid(IL) catalysts [Cmim]PMoO/Am TiO(amorphous TiO) were synthesized through a one-step method for extraction coupled catalytic oxidative desulfurization(ECODS) system. Characterizations such as FTIR... Supported ionic liquid(IL) catalysts [Cmim]PMoO/Am TiO(amorphous TiO) were synthesized through a one-step method for extraction coupled catalytic oxidative desulfurization(ECODS) system. Characterizations such as FTIR, DRS,wide-angle XRD, Nadsorption–desorption and XPS were applied to analyze the morphology and Keggin structure of the catalysts. In ECODS with hydrogen peroxide as the oxidant, it was found that ILs with longer alkyl chains in the cationic moiety had a better effect on the removal of dibenzothiophene. The desulfurization could reach 100% under optimal conditions, and GC–MS analysis was employed to detect the oxidized product after the reaction. Factors affecting the desulfurization efficiencies were discussed, and a possible mechanism was proposed. In addition, cyclic experiments were also conducted to investigate the recyclability of the supported catalyst. The catalytic activity of [Cmim]PMoO/Am TiOonly dropped from 100% to 92.9% after ten cycles, demonstrating the good recycling performance of the catalyst and its potential industrial application. 展开更多
关键词 Supported ionic liquid catalyst polyoxometallate Oxidative desulfurization Amorphous TiO_2 DIBENZOTHIOPHENE
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Supramolecular Structural Inorganic-organic Hybrid[(4-Bromoanilimiun)([18]crown-6)]3[PMo(12)O(40)]·CH3CN 被引量:1
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作者 张裕恒 曹晟 +1 位作者 吕少仿 熊俊 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第8期1272-1278,共7页
A novel supramolecular structural inorganic-organic hybrid [(4-bromoanilimiun)([18]crown-6)]3[PMo(12)O40]·CH3 CN has been synthesized through standard solvent evaporated method. The structure of the title c... A novel supramolecular structural inorganic-organic hybrid [(4-bromoanilimiun)([18]crown-6)]3[PMo(12)O40]·CH3 CN has been synthesized through standard solvent evaporated method. The structure of the title compound was determined through single-crystal X-ray diffraction analysis. It crystallizes in monoclinic system with P21/n space group. The crystal data are a = 18.9529(4), b = 26.4444(5), c = 19.0985(4) A, β = 90.132(6)o, V = 9572.1(3) A^3, Z = 4, Dc= 2.203 g·cm^(–1), μ = 14.956 mm^(–1), F(000) = 6192, S = 1.098, the final R = 0.0859 and w R(I 〉 2σ(I)) = 0.2100. Supramolecular cations are constructed through strong N–H…O hydrogen bonding interaction between the six oxygen atoms of [18]crown-6 molecule and nitrogen atom of(4-bromoanilimiun) cation. Three kinds of different arranged supramolecular cations exist in the title compound, which are filled into the large space formed by [PMo(12)O40] polyoxoanions. Thermogravimentic differential thermal analysis revealed that hydrogen bonding interaction and intermolecular interaction play an important role in maintaining the stability of the title compound. 展开更多
关键词 supramolecular structure inorganic-organic hybrids polyoxometallateS crownether
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Synthesis, Characterization and Conductivity of α-Keggin-type Nanoparticles, Co(en)_3PMo_(12)O_(40)·8H_2O with Optical Activity
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作者 HUANGRu-dan LIJuan ZHANGJing 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第1期1-3,共3页
Polyoxometallates Co(en) 3PMo 12O 40·8H 2O(+,-)[abbreviated as PMo 12-Co(+,-)], nanoparticles were synthesized by the chemical precipitation reaction at room temperature for the first time. They were c... Polyoxometallates Co(en) 3PMo 12O 40·8H 2O(+,-)[abbreviated as PMo 12-Co(+,-)], nanoparticles were synthesized by the chemical precipitation reaction at room temperature for the first time. They were characterized by means of elemental analyses, IR spectrometry and X-ray diffraction. The images of scanning electron microscopy(SEM) and the results of calculation by using the Scherrer equation for the line widths of the XRD patterns were used to estimate the average particle size of the powder products, which was 40 nm. The results show that the nanoparticle size was affected by starting materials′ concentrations. The particles had a small size and a narrow distribution, when the concentrations of H 3PMo 12O 40·24H 2O and Co(en) 3I 3·H 2O were around 1.7×10 -4 and 1.0×10 -3 mol/L, respectively. When the concentration was increased, there was no significant increase in the particle size, but more polydisperse Co(en) 3(PMo 12O 40) (+, -) were obtained. In poly(ethylene glycol)(PEG) with an average molecular weight(M W) of 600 g/mol and containing LiClO 4[n(O)/n(Li)=100∶1] as the supporting electrolyte, the conductivity of the composite system increases upon the addition of PMo 12-Co(+ or -) nanoparticles, which was measured by the a.c. impedance technique. The interactions among PEG, LiClO 4, PMo 12, and Co can be used to explain that the PMo 12-Co(+ or -) nanoparticles could promote the conductivity of the PEG-LiClO4-PMo12-Co system. 展开更多
关键词 polyoxometallateS NANOPARTICLES α-Keggin structure Optical activity
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Fabrication of Chemically-Modified Electrode Containing 1:12 Phosphomolybdic Anions by Sol-Gel Technique and Its Electrocatalytic Reduction of BrO_3 ^-Anions
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作者 Wen Bo SONG Chang Qing SUN(Department of Chemistry, Jinn University, Changchun 130023) 《Chinese Chemical Letters》 SCIE CAS CSCD 1998年第12期0-0,共4页
A novel chedrically-modified electrode containing 1:12 phosphomolybdic anions wasachieved on the surface of platinum electrode by the sol-gel technique. The electrode exhibits ahigh catalytic activity towards the elec... A novel chedrically-modified electrode containing 1:12 phosphomolybdic anions wasachieved on the surface of platinum electrode by the sol-gel technique. The electrode exhibits ahigh catalytic activity towards the electroreduction of BrO3- anions. 展开更多
关键词 Chemically-modified electrode ELECTROCATALYSIS polyoxometallateS sol-gel technique
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Iron-glutamate-silicotungstate ternary complex as highly active heterogeneous Fenton-like catalyst for 4-chlorophenol degradation 被引量:5
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作者 尹冬菊 张立忠 +2 位作者 赵秀峰 陈汉 翟倩 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2015年第12期2203-2210,共8页
A novel iron-glutamate-silicotungstate ternary complex(FeШGluS iW) was synthesized from ferric chloride(FeI II),glutamic acid(Glu),and silicotungstic acid(SiW),and used as a heterogeneous Fenton-like catalyst... A novel iron-glutamate-silicotungstate ternary complex(FeШGluS iW) was synthesized from ferric chloride(FeI II),glutamic acid(Glu),and silicotungstic acid(SiW),and used as a heterogeneous Fenton-like catalyst for 4-chlorophenol(4-CP) degradation at neutral pH value. The prepared FeШGluS iW was characterized using inductively coupled plasma atomic emission spectroscopy,thermogravimetry,Fourier-transform infrared spectroscopy,ultraviolet-visible diffuse reflectance spectroscopy,X-ray diffraction,and field-emission scanning electron microscopy. The results showed that FeШGluS iW has the formula [Fe(C5H8NO4)(H2O)]2SiW 12O40?13H2O,with glutamate moiety and Keggin-structured SiW 12O404- heteropolyanion. The catalyst showed high catalytic activity in 4-CP degradation in the dark and under irradiation. Under the conditions of 4-CP 100 mg/L,FeШGluS iW 1.0 g/L,H2O2 20 mmol/L,and pH = 6.5,4-CP was completely decomposed in 40 min in the dark and in 15 min under irradiation. When the reaction time was prolonged to 2 h,the corresponding total organic carbon removals under dark and irradiated conditions were ca. 27% and 72%,respectively. The high catalytic activity of FeI IIGluS iW is resulted from hydrogen bonding of H2O2 on the FeI IIGluS iW surface. The enhanced degradation of 4-CP under irradiation arises from simultaneous oxidation of 4-CP through Fenton-like and photocatalytic processes respectively catalyzed by ferric iron and the SiW 12O404- hetropolyanion in FeШGluS iW. 展开更多
关键词 POLYOXOMETALATE SILICOTUNGSTATE Heterogeneous catalysis Fenton oxidation 4-Chlorophenol degradation
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Research advances of light-driven hydrogen evolution using polyoxometalate-based catalysts 被引量:10
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作者 Mo Zhang Huijie Li +2 位作者 Junhao Zhang Hongjin Lv Guo-Yu Yang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第6期855-871,共17页
With the increasing concerns to energy shortage and environmental problems in modern society,the development of cheap,clean,and sustainable energy alternatives has been attracting tremendous attention globally.Among v... With the increasing concerns to energy shortage and environmental problems in modern society,the development of cheap,clean,and sustainable energy alternatives has been attracting tremendous attention globally.Among various strategies of renewable energy exploration,solar-driven water splitting into its compositional elements H2 and O2 is an ideal approach to convert and store renewable solar energy into chemical bonds.In recent few decades,as an emerging new type of catalysts,polyoxometalates(POMs)have been widely utilized for water splitting due to their versatile synthetic methodology and highly tunable physicochemical and photochemical properties.This critical review addresses the research advances of light-driven hydrogen evolution using polyoxometalate-based catalysts,including plenary POMs,transition-metal-substituted POMs,POM@MOF composites,and POM-semiconductor hybrids,under UV,near UV and visible light irradiation.In addition,the catalytic mechanism for each reaction system has been thoroughly discussed and summarized.Finally,a comprehensive outlook of this research area is also prospected. 展开更多
关键词 POLYOXOMETALATES Light-driven hydrogen evolution POM@MOF composites POM-semiconductor hybrids Catalytic mechanism
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Polyoxometalates-engineered hydrogen generation rate and durability of Pt/CNT catalysts from ammonia borane 被引量:5
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作者 Wenzhao Fu Chen Han +6 位作者 Dali Li Wenyao Chen Jian Ji Gang Qian Weikang Yuan Xuezhi Duan Xinggui Zhou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第2期142-148,共7页
Heterogeneously catalyzed hydrolytic dehydrogenation of ammonia borane is a remarkable structure sensitive reaction. In this work, a strategy by using polyoxometalates(POMs) as the ligands is proposed to engineer the ... Heterogeneously catalyzed hydrolytic dehydrogenation of ammonia borane is a remarkable structure sensitive reaction. In this work, a strategy by using polyoxometalates(POMs) as the ligands is proposed to engineer the surface and electronic properties of Pt/CNT catalysts toward the enhanced hydrogen generation rate and durability. Three kinds of POMs, i.e., silicotungstic acid(STA), phosphotungstic acid(PTA)and molybdophosphoric acid(PMA), are comparatively studied, among which the STA shows positive effects on the catalytic activity and durability. A catalyst structure-performance relationship is established by a combination of kinetic and isotopic analyses with multiple characterization techniques, such as HAADF-STEM, EDS, Raman spectroscopy and XPS. It is shown that the STA compared to the other two POMs can increase the Pt binding energy and thus promote the reaction. The insights demonstrated here could open a new avenue for boosting the reaction by employing the POMs as the ligands to engineer the catalyst electronic properties. 展开更多
关键词 POLYOXOMETALATES Pt/CNT ELECTRONIC properties HYDROGEN generation DURABILITY
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Catalytic oxidative desulfurization of fuels in acidic deep eutectic solvents with [(C_6H_(13))_3P(C_(14)H_(29))]_3PMo_(12)O_(40) as a catalyst 被引量:6
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作者 Wei Jiang Hao Jia +5 位作者 Zhanglong Zheng Linhua Zhu Lei Dong Wei Liu Wenshuai Zhu Huaming Li 《Petroleum Science》 SCIE CAS CSCD 2018年第4期841-848,共8页
Deep eutectic solvents(DESs) are a new class of green solvents analogous to ionic liquids due to their biodegradable capacity and low cost. However, the direct extractive desulfurization of diesel oil by DESs cannot m... Deep eutectic solvents(DESs) are a new class of green solvents analogous to ionic liquids due to their biodegradable capacity and low cost. However, the direct extractive desulfurization of diesel oil by DESs cannot meet the government’s standard. In this work, amphiphilic polyoxometalates were synthesized and characterized by FT-IR and mass spectrometry.The oxidative desulfurization results showed that benzothiophene(BT) could be completely removed by employing a [(CH)P(CH)]PMoO, DES(ChCl/2 Ac) and HOsystem. It was also found that the organic cation of catalysts played a positive role in oxidative desulfurization. The reaction conditions, such as reaction temperature and time, the amount of catalyst and DES and HO/S(O/S) molar ratio, were optimized. Different sulfides were tested to determine the desulfurization selectivity of the optimal reaction system, and it was found that 97.2% of dibenzothiophene(DBT) could be removed followed by 80.7% of 4-MDBT and 76.0% of 4,6-DMDBT. After reaction, the IR spectra showed that the catalyst [(CH)P(CH)]PMoOwas stable during the reaction process and the oxidative product was dibenzothiophene sulfone(DBTO). Furthermore, the catalyst can be regenerated and recycled for four runs with little loss of activity. 展开更多
关键词 DIESEL Oxidative desulfurization Deep eutectic solvents POLYOXOMETALATES H_2O_2
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Synthesis and Structure Investigation of a Transition Metal Ion Bridging Bis(diphosphopentamolybdates),[H_2BIIM]_3[HBIIM]_4[Mn(H_2O)_4(P_2Mo_5O_(23))_2]·7H_2O 被引量:6
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作者 魏林恒 王子梁 +1 位作者 赵俊伟 王敬平 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第5期784-788,共5页
A novel transition metal ion bridging bis(diphosphopentamolybdates) has been synthesized and characterized by elemental analysis,IR spectrum,UV spectrum and single-crystal X-ray diffraction.The single-crystal struct... A novel transition metal ion bridging bis(diphosphopentamolybdates) has been synthesized and characterized by elemental analysis,IR spectrum,UV spectrum and single-crystal X-ray diffraction.The single-crystal structure analysis shows that the compound consists of seven charge-compensating 2,2'-biimidazole cations (BIIM=2,2'-biimidazole) and one dumbbell-like [Mn(H2O)4(P2Mo5O23)2]10-heteropolyanion which is constructed by two [P2Mo5O23]6-clusters bridged through one [Mn(H2O)4]2+ cation. 展开更多
关键词 POLYOXOMETALATE MOLYBDATE crystal structure dumbbell-like PHOSPHATE
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Inhibition of α/β-K_6P_2W_(18)O_(62)·10H_2O on the Activity of Mushroom Tyrosinase and Its Antimicrobial Effects 被引量:5
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作者 HU Xi-yu CHEN Bing-man +1 位作者 WANG Li CHEN Fa-he 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第5期862-865,共4页
Dawson-type phosphotungstic polyoxometalate α/β-K6P2W18O62·10H2O(P2W18) was synthesized and its inhibitory effect on the mushroom tyrosinase was investigated. It could inhibit diphenolase activity of mushroom... Dawson-type phosphotungstic polyoxometalate α/β-K6P2W18O62·10H2O(P2W18) was synthesized and its inhibitory effect on the mushroom tyrosinase was investigated. It could inhibit diphenolase activity of mushroom tyrosinase as an irreversible inhibitor. When the concentration of the enzyme reached 0.0176 mg/mL, the concentration of P2W18 leading to 50% activity lost(IC50) was 0.05 mmol/L for monophenolase and 0.64 mmol/L for diphenolase. In addition, the antimicrobial activity of P2W18 was evaluated by zone of inhibition test. The results show that P2W18 possesses effective antimicrobial ability against Escherichia coli, Bacillus subtilis, yeast, especially Escherichia coli and yeast. 展开更多
关键词 POLYOXOMETALATE Mushroom tyrosianse INHIBITION Antimicrobial activity
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