Enhanced formaldehyde oxidation on CeO2/AlOOH-supported Pt catalyst at room temperature

Abstract

A CeO2/AlOOH-supported Pt catalyst was prepared by combining the microemulsion-assisted synthesis of AlOOH and CeO2 hybrid with NaBH4-reduction of Pt precursor. The as-prepared catalyst obtained by depositing Pt nanoparticles on the CeO2/AlOOH (1:9 molar ratio) support (Pt/Al9Ce1) exhibited a remarkable catalytic activity and stability for oxidative removal of formaldehyde (HCHO) vapor at room temperature. The excellent performance of Pt/Al9Ce1 catalyst could be attributed to the abundance of surface hydroxyls, oxygen storage in CeO2, high dispersion of Pt nanoparticles, and excellent adsorption performance of AlOOH. The mechanism of HCHO decomposition was investigated with respect to the behavior of adsorbed intermediates on the Pt/Al9Ce1 surface at room temperature using in situ DRIFTS. The results suggest that the main species formed on the surface during HCHO oxidation are the reaction intermediates, which could be directly oxidized to CO2 in the presence of O2. By taking advantage of high adsorption affinity of AlOOH nanoflakes toward HCHO, reducible ceria nanoparticles and excellent catalytic activity of Pt nanoparticles toward HCHO oxidation, it was possible to design a superior nanostructured catalyst for room temperature decomposition of HCHO. This strategy can be also applied to fabricate novel nanostructured catalysts for advanced applications such as environmental remediation.