Ru‐RuO 2 Coordinated with Si‐Supported GaN Nanowires for Light‐Driven Simultaneous Activation of CO 2 and H 2 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.