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| Type |
Poster Presentation |
| Area |
Inorganic Chemistry |
| Room No. |
Event Hall |
| Time |
4월 19일 (목요일) 11:00~12:30 |
| Code |
INOR.P-79 |
| Subject |
Mechanism Study of Photocatalytic Hydrogen Evolution by Well-Defined Metal-Semiconductor Nanodumbbells |
| Authors |
Ji Yong Choi, Hyunjoon Song*
Department of Chemistry, Korea Advanced Institute of Science and Technology, Korea
|
| Abstract |
Semiconductor-metal hybrid nanostructures are one of the best model catalysts for understanding photocatalytic hydrogen generation. To investigate the optimal structure of metal co-catalysts, metal-CdSe-metal nanodumbbells were synthesized with three distinct sets of metal tips, Pt-CdSe-Pt, Au-CdSe-Au, and Au-CdSe-Pt. Photoelectrochemical responses and transient absorption spectra showed that the competition between the charge recombination at the metal-CdSe interface and the water reduction on the metal surface is a detrimental factor for the apparent hydrogen evolution rate. For instance, a large recombination rate (krec) at the Pt-CdSe interface limits the quantum yield of hydrogen generation despite a superior water reduction rate (kWR) on the Pt surface. To suppress the recombination process, Pt was selectively deposited onto the Au tips of Au-CdSe-Au nanodumbbells, in which the krec was diminished at the Au-CdSe interface, and the large kWR was maintained on the Pt surface. As a result, the optimal structure of the Pt-coated Au-CdSe-Au nanodumbbells reached a quantum yield of 4.84%. These findings successfully demonstrate that the rational design of a metal co-catalyst and metal-semiconductor interface can additionally enhance the catalytic performance of the photochemical hydrogen generation reactions. |
| E-mail |
jy1129@kaist.ac.kr |
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121st General Meeting of the KCS