CeO₂ Nanorods Decorated with Pt Nanoparticles as Catalysts for Oxidative Elimination of Formaldehyde

Indoor HCHO elimination is of great significance for breathing safety. Herein, we report CeO2 nanorods decorated by Pt nanoparticles for HCHO oxidative elimination. The resultant Pt/CeO2 catalysts show a close relationship between oxidation performance and ceria nanorod crystallite sizes. In comparison to 0.2Pt/CeO2-B and 0.2Pt/CeO2-C catalysts that have ceria crystallite sizes of 11 and 18 nm, respectively, the 0.2Pt/CeO2-A catalyst that has a ceria crystallite size of 8 nm exhibits the highest oxidation performance. From the results of Raman, O2-TPD, and H2-TPR analyses, the size–performance relationship is suggested to be contributed from the highest oxygen vacancy, the highest oxygen mobility, and the strongest redox in the 0.2Pt/CeO2-A catalyst because of the smallest ceria size. In situ DRIFTS verifies that mobile oxygen from the ceria surface lattice oxygen activated the oxygen molecules at the oxygen vacancy and the hydroxyl group transformed the intermediates of dioxymethylene and formate species.