Dual Plasmonic Fields Enable High‐Density Hot‐Electron Generation with Stepwise Charge Transfer Directed to Oxygen Reduction Sites for Enhanced Artificial Photosynthesis of H2O2

Abstract

Artificial H₂O₂ photosynthesis via plasmonic heterojunction photocatalysts represents a promising route for solar‐to‐chemical energy conversion. However, traditional systems are often limited by inefficient charge separation, inadequate utilization of hot electrons, and non‐specific reaction sites, resulting in suboptimal H₂O₂ production. Here, we present a catalyst architecture that achieves high‐density hot‐electron generation with stepwise charge transfer directed to oxygen reduction sites, boosting H₂O₂ photosynthesis. The catalyst comprises ZnIn₂S₄ (ZIS) nanosheets integrated with two non‐noble plasmonic semiconductors, W18O49 nanoneedles and MoO3‐X nanosheets. This configuration leverages dual sites for localized surface plasmon resonance (LSPR) to amplify hot‐electron production while enabling sequential charge migration through the double S‐scheme, guiding electrons to reduction sites while minimizing recombination. The optimized Dual‐LSPR‐Double‐S‐Scheme (DLDS) catalyst exhibits a superior H2O2 production rate of 51.3 µmol g⁻¹ min⁻¹ under UV–vis light and 13.6 µmol g⁻¹ min⁻¹ under visible light. Spectroscopic analyses (fs‐TA, XPS, in‐situ DRIFTS) confirm rapid carrier dynamics, efficient hot‐electron accumulation, and formation of reactive oxygen intermediates (*O₂⁻, *OOH) at targeted sites. Theoretical calculations reveal enhanced local electric fields from dual LSPR, corroborating accelerated hot‐electron migration. The produced H₂O₂ is further evaluated for practical applications, including the detoxification of poisoned plants and bacterial inactivation, demonstrating its potential in environmental remediation.