Pt/oxide nanocatalysts synthesized via the ultrasonic spray pyrolysis process: engineering metal-oxide interfaces for enhanced catalytic activity

Abstract

We show that Pt nanoparticles synthesized on oxide nanocatalysts exhibit catalytic activity enhancement depending on the type of the oxide support. To synthesize the Pt/oxide nanocatalysts, we employed a versatile synthesis method using Pt nanoparticles (NPs) supported on various metal oxides (i.e., SiO2, CeO2, Al2O3, and FeAl2O4) utilizing ultrasonic spray pyrolysis. Catalytic CO oxidation was carried out on these catalysts, and it was found that the catalytic activity of the Pt NPs varied depending on the supporting oxide. While Pt/CeO2 exhibited the highest metal dispersion and active surface area, Pt/FeAl2O4 exhibited the lowest active surface area. Among the Pt/oxide nanocatalysts, Pt NPs supported on CeO2 showed the highest catalytic activity. We ascribe the enhancement in turnover frequency of the Pt/CeO2 nanocatalysts to strong metal-support interactions due to charge transport between the metal catalysts and the oxide support. Such Pt/oxide nanocatalysts synthesized via spray pyrolysis offer potential possibilities for large-scale synthesis of tailored catalytic systems for technologically relevant applications.