Excited-State Interaction at the Interface of Semiconductor and Adsorbed Metal Complex

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K18932
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 32:Physical chemistry, functional solid state chemistry, and related fields
• Research Institution: Kyoto University
• Principal Investigator: Imahori Hiroshi 京都大学, 工学研究科, 教授 (90243261)
• Project Period (FY): 2021-07-09 – 2024-03-31
• Keywords: 光電荷分離 / 酸化チタン / 貴金属 / 界面 / エネルギー変換 / 色素増感太陽電池

Outline of Final Research Achievements

In solar cells and photocatalysts, a high photoinduced charge separation efficiency is essential to achieve high power conversion efficiency. Plasmon energy conversion using precious metal nanoparticles is one promising method for this, but there is a limit to the enhancement effect. Therefore, this study focused on photoinduced charge separation at the heterogeneous hybrid interface of a dye containing precious metal elements and a semiconductor. We found that a dye molecule containing gold atoms is immobilized on the surface of titanium oxide through multiple carboxyl groups, and ultrafast charge separation occurs through direct interaction between the gold atom and titanium oxide. By introducing a donor moiety into this system, we were successful in improving the power conversion efficiency.

Free Research Field

光化学

Academic Significance and Societal Importance of the Research Achievements

色素増感太陽電池では、増感色素の分子設計がエネルギー変換効率を決める重要な因子である。今回、半導体界面での光電荷分離を向上させるために、半導体表面に平行に平面状の増感色素が配向・吸着しても、さらにその上に電子ドナー部位を付加することでエネルギー変換効率を向上できることを学術的に明らかにした。本研究成果は将来的に半導体/増感色素界面材料を光エネルギー変換に利用するための重要な足掛かりになり得る。