Electrochemical investigation of the energetics of particulate titanium dioxide photocatalysts. The methyl viologen-acetate system
Electrochemical investigation of the energetics of particulate titanium dioxide photocatalysts. The methyl viologen-acetate system
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DOI：
10.1021/ja00339a007
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发表时间：
1983
影响因子：
15
通讯作者：
M. Ward;James R. White;A. Bard
中科院分区：
文献类型：
--
作者：
M. Ward;James R. White;A. Bard
添加甲基紫精 (MV/sup 2 +/) 通过捕获光生电子并形成 MV/sup +/，增强了在光照下观察到的 TiO/sub 2/ 悬浮液的阳极电流。光电流的大小取决于半导体费米能级和MV/sup 2 +//MV/sup +/. Couple 的E/sub redox/ 的相对位置。根据观察到的光电流随 pH 的变化，锐钛矿粉末中费米能级的位置估计为 -0.05 V vs. NHE (pH 0)。还讨论了准费米能级随光强度的变化。
Addition of methyl viologen (MV/sup 2 +/) enhances the anodic currents observed for TiO/sub 2/ suspensions under illumination by trapping of photogenerated electrons with formation of MV/sup +/. The magnitude of the photocurrent depends upon the relative location of the semiconductor Fermi level and E/sub redox/ of the MV/sup 2 +//MV/sup +/.couple. The location of the Fermi level in the anatase powders was estimated as -0.05 V vs. NHE (pH 0) based on the observed variation of photocurrent with pH. The shift in the quasi-Fermi level with light intensity is also discussed.