Plasmonic p–n Junction for Infrared Light to Chemical Energy Conversion

• DOI: 10.1021/jacs.8b11544
• Publication Date: 2018-12-19T01:16:25Z
• Authors: Zichao Lian; Masanori Sakamoto; Junie J. M. Vequizo; C. S. Kumara Rana...; Akira Yamakata; Takuro Nagai; Koji Kimoto; Yoichi Kobayashi; Naoto Tamai; Toshiharu Teranishi
• Keywords: Carriers; Water; Electron-Transfer; Exchange; 02 engineering and technology; 0210 nano-technology; 01 natural sciences; 7. Clean energy; Hydrogen; 0104 chemical sciences

Infrared (IR) light represents an untapped energy source accounting for almost half of all solar energy. Thus, there is a need to develop systems to convert IR light to fuel and make full use of this plentiful resource. Herein, we report photocatalytic H2 evolution driven by near- to shortwave-IR light (up to 2500 nm) irradiation, based on novel CdS/Cu7S4 heterostructured nanocrystals. The apparent quantum yield reached 3.8% at 1100 nm, which exceeds the highest efficiencies achieved by IR light energy conversion systems reported to date. Spectroscopic results revealed that plasmon-induced hot-electron injection at p-n heterojunctions realizes exceptionally long-lived charge separation (>273 μs), which results in efficient IR light to hydrogen conversion. These results pave the way for the exploration of undeveloped low-energy light for solar fuel generation.