Hierarchical Co₃O₄-NiO hollow dodecahedron-supported Pt for room-temperature catalytic formaldehyde decomposition

Room-temperature catalytic decomposition is considered a predominant approach for the continuous and efficient elimination of indoor formaldehyde (HCHO). Herein, Co₃O₄-NiO hollow dodecahedra were prepared by using ZIF-67 as a precursor and decorated with 0.3 wt% platinum nanoparticles (Pt NPs). The hierarchical porous Pt/Co₃O₄-NiO catalyst exhibited an excellent room-temperature HCHO decomposition performance, and 93% conversion was achieved within 60 min. Numerous active oxygens at the interface between Co₃O₄ and NiO and the oxygen vacancies generated during Pt deposition were favorable for the adsorption and conversion of HCHO to Dioxymethylene (DOM). Moreover, the electron transfer from NiO to Pt rendered Pt NPs more effective in adsorbing and activating O₂ molecules, thereby promoting the further oxidation of DOM to formate and CO₂. Importantly, the hierarchical structure of the Co₃O₄-NiO support with a large surface area participated in the uniform distribution and easy accessibility of Pt active sites. In addition, the hollow and porous structure enabled Pt/Co₃O₄-NiO catalyst to possess ultra-low gas resistance, which is important for gas–solid HCHO oxidation. This work may provide clues for the fabrication of MOF-derived catalysts for HCHO decomposition with high efficiency. Copyright © 2021 Elsevier B.V. All rights reserved.