Promoting Formation and Suppressing Decomposition of H <sub>2</sub> O <sub>2</sub> via Photocarrier Flow at Au@TiO <sub>2</sub> Interfaces
Yicui Kang, Yao Tan, Wenjie Tian, Huayang Zhang, Qin Chen, Jun Wang, Olivier Henrotte, Dominik Kammerer, Quinten A. Akkerman, Chenghao Fan, Diya Xie, Li Zhu, Junwei Fu, Min Liu, Emiliano Cortés
Abstract
High Resolution Image Download MS PowerPoint Slide Hydrogen peroxide (H 2 O 2 ) is an attractive green oxidant and energy carrier, but its industrial production remains energy- and resource-intensive. Photocatalytic synthesis from O 2 and H 2 O offers a safer and more sustainable alternative, yet its efficiency is hampered by sluggish formation and rapid decomposition pathways. Here, we demonstrate a plasmon-engineered strategy to overcome both challenges using Au@TiO 2 core–shell nanostructures. The nanocubic Au@TiO 2 (NC@TiO 2 ) achieves a remarkable H 2 O 2 production rate of 350.5 mM h –1 g –1 under full-spectrum irradiation −1.6 times higher formation and 47% lower decomposition compared to bare TiO 2 . Spectroscopic analysis and simulations reveal that localized surface plasmon resonance (LSPR) in the Au core orchestrates photocarrier dynamics: electrons generated in TiO 2 are funneled to Au sites to drive O 2 reduction, while plasmonic hot electrons neutralize TiO 2 holes that would otherwise decompose H 2 O 2 . The morphology dependence of this effect is evident: NC@TiO 2 with stronger LSPR outperforms rhombic dodecahedral Au@TiO 2 . These results establish plasmon-mediated charge steering as a powerful tool to enhance both efficiency and selectivity in solar-to-chemical conversion, providing a design principle for next-generation photocatalysts.