Ru-RuO2 Coordinated with Si-Supported GaN Nanowires for Light-Driven Simultaneous Activation of CO2 and H2 to Achieve Exceptional Reverse Water-Gas Shift Reaction.

The reverse water-gas shift (RWGS) reaction presents an industrial promise for carbon dioxide valorization. In this work, a dual-site Ru-RuO2 cocatalyst anchored on Si-supported GaN nanowires (NWs) is developed for solar-powered CO2-to-CO conversion. The assembled Si-supported GaN NWs/Ru-RuO2 delivers a considerable CO rate of 57.89 mmol·cm-2·h-1 with nearly 100% selectivity under illumination at 5.5 W·cm-2 without external heating, along with a remarkable turnover frequency of 2.28 × 105 h-1. The temperature-programmed desorption, in situ spectroscopic characterization, and DFT calculations collectively reveal that the Si-supported GaN NWs/Ru-RuO2 enables simultaneous activation of CO2 and H2. Moreover, the synergy between Ru-RuO2 and GaN substantially reduces the reaction energy barrier from 0.83 to 0.64 eV via the key *COOH intermediate, thereby establishing a new benchmark for light-driven RWGS efficiency. This work provides a strategic design for high-performance CO2-to-CO conversion and opens avenues for downstream synthetic applications.