Tribridged hydroxyl groups regulated by Ni/La ratio for enhanced ozone decomposition over Ni-La bimetallic basic carbonate catalysts

This study investigates the application of the Ni 2 La 1 bimetallic basic carbonate catalyst in ozone decomposition, which demonstrates excellent catalytic activity under both low-humidity and high-humidity conditions (90 % relative humidity). The catalyst was synthesized via a co-precipitation method, with the Ni/La molar ratio (Ni:La = 2:1) optimized to enhance its structural and functional properties. This optimization endowed the Ni 2 La 1 catalyst with a more developed layered structure, providing an increased number of surface active sites, which significantly improved its catalytic activity and stability. The results indicate that the Ni 2 La 1 catalyst achieves an ozone decomposition conversion efficiency exceeding 90 % under high-humidity conditions and maintains stable catalytic performance over a continuous operation period of 48 hours. Mechanistic studies further reveal that tribridged hydroxyl groups serve as the primary active sites and play a crucial role in the ozone decomposition reaction. Additionally, the Ni 2 La 1 catalyst exhibits a unique hydroxyl regeneration mechanism, where strong interactions with water molecules facilitate the continuous regeneration of tribridged hydroxyl groups, thereby ensuring stability and sustained catalytic activity in humid environments. This research provides a new pathway for the application of Ni-La bimetallic basic carbonate catalysts in environmental catalysis and green chemical reactions. In particular, it offers robust theoretical support and practical insights for ozone mitigation technologies under high-humidity conditions.