Photoelectrocatalytic CO2 reduction to C1 and C2 products via virus-like carrier transfer in Cu2O-au@TiO2

The highly selective generation of products in the photoelectrocatalytic (PEC) CO 2 reduction reaction is significantly hindered by the complex multi-electron transfer process. In this work, we designed and synthesized a Cu 2 O-Au@TiO 2 composite with a unique “core–shell–satellite” architecture via a facile wet-chemical approach. In this architecture, the Au nanocore strengthens visible-light harvesting through localized surface plasmon resonance (SPR) and injects hot electrons into the mesoporous TiO 2 shell, while the outer Cu 2 O selectively exposes highly active (111) facets and establishes low-mismatch interfaces with TiO 2 . This configuration promotes directional charge migration through virus-like synaptic channels, thereby accelerating multi-electron CO 2 reduction. The cooperative mechanism of SPR enhancement, crystallographic facet matching, and dynamic charge transfer enables efficient and selective conversion of CO 2 to C 2 H 4 . Under visible-light irradiation and applied potential, the optimized composite achieves a remarkable C 2 H 4 yield of 174 ± 3.2 μmol·cm −2 ·h −1 with a sustained current density exceeding 75 mA·cm −2 . These findings highlight a rational structural design that synergistically couples plasmonic excitation with interfacial charge management, establishing a promising paradigm for developing high-performance photoelectrocatalytic systems toward solar-driven CO 2 reduction.