Hygroscopic La₂O₃ hybridized LaCoO₃-based composite catalyst for efficient ozone decomposition under humidity conditions

Herein we first report the unique hygroscopic oxide hybrid LaCoO₃-based composite catalyst derived from dual-metal metal organic framework (MOF) for ozone decomposition. First, dual-metal La,Co-MOF is synthesized by solvothermal method, then La,Co-MOF is calcined at high temperature, the hygroscopic oxide (La₂O₃) and active oxides (LaCoO₃ and Co₃O₄) were uniformly hybridized to form porous microspheres. Benefiting from the hybrid action of the two types of oxides, this composite catalyst exhibits highly efficient O₃ removal activity within 12 h over the entire humidity conditions. The outstanding humidity resistance is attributed to the preferential adsorption of water vapor on hygroscopic oxide (La₂O₃), preventing the adsorption of gaseous water molecules on the surface of active oxides. In-situ FTIR further indicates that this composite catalyst possesses superior humidity resistance in the ozone catalytic decomposition.