Ag Nanoparticle-Decorated GaN/β-Ga₂O₃ Core–Shell Nanowires as Catalysts for Highly Efficient CO₂-to-CO Photocatalytic Conversion

Solar-driven photocatalytic CO 2 conversion is a promising strategy to alleviate the energy crisis and reduce the level of CO 2 emissions. In this study, GaN@β-Ga 2 O 3 core–shell nanowire (NW) arrays were prepared via the thermal oxidation of GaN NWs, and their photocatalytic CO 2 reduction performance was investigated. GaN@β-Ga 2 O 3 NWs exhibited superior photocatalytic activity compared to GaN NWs and β-Ga 2 O 3 NWs under simulated sunlight irradiation. The average CO production rate reached ∼447.30 μmol g –1 h –1 within 3 h. The photocatalytic reduction process was further enhanced using GaN@β-Ga 2 O 3 NWs with Ag nanoparticles of ∼18 nm size as cocatalysts, and its average rate increased to ∼689.18 μmol g –1 h –1 . The ternary heterostructured photocatalyst demonstrated excellent synergistic effects and high efficiency in environmental protection and energy conversion applications.