Electrochemical Method for Studying the Kinetics of Electron Recombination and Transfer Reactions in Heterogeneous Photocatalysis: The Effect of Fluorination on TiO2 Nanoporous Layers
Electrochemical Method for Studying the Kinetics of Electron Recombination and Transfer Reactions in Heterogeneous Photocatalysis: The Effect of Fluorination on TiO2 Nanoporous Layers
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DOI：
10.1021/jp075672r
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发表时间：
2008
影响因子：
3.7
通讯作者：
D. Monllor-Satoca;R. Gómez
中科院分区：
文献类型：
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作者：
D. Monllor-Satoca;R. Gómez
提出了一种电化学方法，用于评估光催化剂在光照下产生的电子的复合和转移到溶液中的速率常数。它是基于在黑暗中的伏安测量和开路光电位弛豫测量与纳米多孔薄膜电极完成的组合。不仅平均一阶速率常数的电子消耗，以这样的方式获得，但也作为电极电位的函数（微正则速率常数），这些常数的值。这种方法适用于不同的二氧化钛样品，以阐明的效果上的电子复合（与表面捕获的空穴）和电子转移到溶解氧的速率。在这两种情况下，但特别是对于重组，有，在催化剂，一个显着的延迟的电子消耗过程中发现的文献中的几个光催化研究协议。最后，我们提前…
An electrochemical method for evaluating the rate constants of recombination and transfer to solution for electrons generated upon illumination of TiO2 photocatalysts is presented. It is based on the combination of voltammetric measurements in the dark and open circuit photopotential relaxation measurements done with nanoporous thin film electrodes. Not only the average first-order rate constants for electron consumption are obtained in such a way but also the values of such constants as a function of the electrode potential (microcanonical rate constants). This method is applied to different titanium dioxide samples as to elucidate the effect of fluorination on the rate of both electron recombination (with surface trapped holes) and electron transfer to dissolved oxygen. In both cases, but especially for recombination, there is, upon fluorination, a significant retardation of the electron consumption process in agreement with several photocatalytic studies found in the literature. Finally, we take advant...