Behavior of photogenerated charge carriers on visible-light responsive photocatalysts

2015 Fiscal Year Final Research Report

• Project/Area Number: 23360360
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Catalyst/Resource chemical process
• Research Institution: Toyota Technological Institute
• Principal Investigator: YAMAKATA AKIRA 豊田工業大学, 工学(系)研究科(研究院), 准教授 (60321915)
• Project Period (FY): 2011-04-01 – 2016-03-31
• Keywords: 光触媒 / キャリアーダイナミクス / 再結合 / 電荷移動 / 水分解 / 時間分解分光

Outline of Final Research Achievements

Photocatalytic activity is determined by the competition between the charge carrier recombination and charge transfer to the reactants molecules. Therefore, in order to improve the photocatalytic activity, the behavior of photogenerated charge carriers should be elucidated and controlled. In this work, we established a new method to study the behavior of photogenerated electrons and holes as well as their energy states by using time-resolved visible to mid-IR absorption spectrometers. We found that most of photogenerated electrons in powder SrTiO3 are trapped at the defects on powders, but the electron-trapping decelerates the recombination and works to enhance photocatalytic activities. Furthermore, when SrTiO3 powders are doped with transition metals such as Ni, the lifetime of charge carriers is much elongated, although it has been widely believed that the doping accelerated the recombination. These information is necessary to develop more efficient photocatalysts.

Free Research Field

表面分光学