Revitalizing platinum: Alkali-promoted formation of active metallic nanoparticles from inert Pt entities for enhanced benzene combustion

Abstract

Pt-based catalysts play a crucial role in the catalytic combustion of benzene. Previous studies have highlighted the significance of metal Pt atoms as the active phase in benzene combustion, while oxidized Pt sites exhibit lower activity. In practical catalysts synthesized through wet chemical methods, a range of metal species is present, including highly dispersed oxidized metal atoms, small oxidized metal clusters, and metal nanoparticles. This paper explores an effective strategy to enhance metal utilization and develop high-performance platinum-based catalysts for benzene catalytic combustion by introducing alkali metals. This approach transforms low-activity oxidized metal atoms and small oxidized metal clusters into active small metal nanoparticles. The introduction of K-O groups displaces Pt from oxygen vacancy trapping sites on antimony-doped tin oxide (ATO) support, enhancing Pt mobility and converting them into active metallic Pt nanoparticles, ultimately improving benzene combustion. These findings highlight the role of alkali metals in promoting catalytic activity and provide insights for designing high-performance noble-metal-based catalysts.