Plasmonic Nickel–TiO2 Heterostructures for Visible‐Light‐Driven Photochemical Reactions

• Published in: Angewandte Chemie International Edition Vol. 58; no. 18; pp. 6038 - 6041
• Main Authors: He, Shuai, Huang, Jiawei, Goodsell, Justin L., Angerhofer, Alexander, Wei, Wei David
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 23.04.2019
• Edition: International ed. in English
• Subjects: dye degradation; EPR spectroscopy; Heavy metals; Heterojunctions; Heterostructures; hot carrier transfer; Hot electrons; Methylene blue; Nickel; Noble metals; Photocatalysis; Photochemical reactions; Photochemicals; surface plasmon; Titanium dioxide; visible light
• ISSN: 1433-7851; 1521-3773; 1521-3773
• DOI: 10.1002/anie.201901987

Plasmon‐mediated carrier transfer (PMCT) at metal–semiconductor heterojunctions has been extensively exploited to drive photochemical reactions, offering intriguing opportunities for solar photocatalysis. However, to date, most studies have been conducted using noble metals. Inexpensive materials capable of generating and transferring hot carriers for photocatalysis via PMCT have been rarely explored. Here, we demonstrate that the plasmon excitation of nickel induces the transfer of both hot electrons and holes from Ni to TiO2 in a rationally designed Ni–TiO2 heterostructure. Furthermore, it is discovered that the transferred hot electrons either occupy oxygen vacancies (VO) or produce Ti3+ on TiO2, while the transferred hot holes are located on surface oxygens at TiO2. Moreover, the transferred hot electrons are identified to play a primary role in driving the degradation of methylene blue (MB). Taken together, our results validate Ni as a promising low‐cost plasmonic material for prompting visible‐light photochemical reactions. Some electrons like it hot: Plasmon‐mediated charge transfer in Ni–TiO2 heterostructures was used to harvest visible‐light energy for photochemical reactions. The plasmon‐generated hot electrons were transferred from Ni to TiO2 to either occupy oxygen vacancies or produce Ti3+, while the plasmon‐generated hot holes were transferred to surface oxygens at TiO2. Furthermore, the transferred hot electrons play a primary role in driving methylene blue degradation.