Efficient Hydrogen-Evolving Cathodes Based on Proton and Electron Reservoir Behaviors of the Phosphotungstate [H7P8W48O184]33- and the Co(II)-Con
详细信息 查看全文
- 作者：Bineta Keita ; Ulrich Kortz ; Luis Roberto Brudna Holzle ; Spencer Brown ; Louis Nadjo
- 刊名：Langmuir
- 出版年：2007
- 出版时间：September 11, 2007
- 年：2007
- 卷：23
- 期：19
- 页码：9531 - 9534
- 全文大小：138K
- 年卷期：v.23,no.19(September 11, 2007)
- ISSN：1520-5827
文摘
Original and simple procedures for glassy carbon electrode modification with polyoxometalates (POMs),phosphotungstate [H7P8W48O184]33-, and Co(II)-containing silicotungstates [Co6(H2O)30{Co9Cl2(OH)3(H2O)9(
-SiW8O31)3}]5- and [{Co3(B--SiW9O33(OH))(B--SiW8O29OH)2}2]22- give stable and very active surfaces for thehydrogen-evolution reaction (HER). For this purpose, the selected POMs fixed on Vulcan XC-72 were adsorbed onthe electrode surface or were directly entrapped in polyvinylpyridine films on the electrode. Cyclic voltammetry andconfocal microscopy results converge to indicate that the activation is related to the proton and electron reservoir-likebehaviors of these molecular oxides and not to any electrode surface area increase. However, the Tafel parametersof the HER process, which are different from one POM to the next, are in the range of those of the best metallicelectrodes.
-SiW8O31)3}]5- and [{Co3(B--SiW9O33(OH))(B--SiW8O29OH)2}2]22- give stable and very active surfaces for thehydrogen-evolution reaction (HER). For this purpose, the selected POMs fixed on Vulcan XC-72 were adsorbed onthe electrode surface or were directly entrapped in polyvinylpyridine films on the electrode. Cyclic voltammetry andconfocal microscopy results converge to indicate that the activation is related to the proton and electron reservoir-likebehaviors of these molecular oxides and not to any electrode surface area increase. However, the Tafel parametersof the HER process, which are different from one POM to the next, are in the range of those of the best metallicelectrodes.