Regulating the chemical state of silver via surface hydroxyl groups to enhance ozone decomposition performance of Ag/Fe2O3 catalyst

Abstract

Catalytic decomposition is a promising method of ozone (O3) removal, and Ag-based catalysts have shown excellent O3 decomposition performance. In this study, the chemical states of Ag species were successfully regulated by varying the loading of Ag and the particle size of α-Fe2O3 supports, and the O3 decomposition performance of different Ag species (monatomic Ag, Ag clusters (1–2 nm), small Ag nanoparticles (3–5 nm), large Ag nanoparticles (7–12 nm)) was determined. The changes undergone by Ag species after exposure to ozone were characterized in detail, and the ozone decomposition performance of the corresponding Ag species was determined. The terminal and doubly bridging hydroxyl groups on the Fe2O3 support were determined to be the anchoring sites for Ag species. The Ag species and Fe2O3 support are connected through oxygen bridges, forming Ag-O-Fe linkages. This study provides guidance for understanding the mechanism of the interaction between metals and supports and follow-up development of high-efficiency Ag-based catalysts.