Synthesis of Highly Tunable Alloy Nanocatalyst through Heterogeneous Doping Method

Adv Sci (Weinh). 2023 Feb;10(5):e2204693. doi: 10.1002/advs.202204693. Epub 2022 Dec 12.

Abstract

The combination of supported metal nanoparticles and functional host oxides catalyze many major industrial reactions. However, uniform dispersion and ideal chemical configuration of such nanoparticles, which determines the catalytic activity, are often difficult to achieve. In this study, a unique combination is proposed of heterogeneous doping and ex-solution for the fabrication of Pt-Ni alloy nanoparticles on CeO2 . By manipulating the reducing conditions, both the particle size and composition are precisely controlled, thereby achieving a highly dispersed and stable alloy nanocatalyst. The unique behavior of controlled alloy composition is elucidated through classical diffusion and precipitation kinetics with elemental analysis of the grain boundaries. Finally, Pt-Ni alloy nanocatalysts are successfully tuned showcasing a breakthrough performance compared to single element catalyst in reverse water gas shift reaction with superior stability and reproducibility.

Keywords: CO oxidation; CeO2; alloy; ex-solution; grain boundary; heterogeneous doping; reverse water gas shift reaction.