文献类型：期刊文献

英文题名：Metal-Support Interaction and Oxygen-Vacancy Enhanced Silver-Based Catalyst on Commercial Support for Low Temperature Trace Formaldehyde Removal

作者：Yang, Xiaohang[1]; Xiao, Chunyan[1]; Zou, Jiaxin[1]; Xiong, Guo[2]; Luo, He'an[1,3]; Jiang, Haibo[4]; Yang, Hongyun[1]

机构：[1] School of Chemical Engineering, Xiangtan University, Xiangtan, 411105, China; [2] Xiangtan Iron & Steel Group Co., Ltd., Xiangtan, 411101, China; [3] National & Local United Engineering Research Center for Chemical Process Simulation and Intensification, Xiangtan University, Xiangtan, 411105, China; [4] School of Material Science and Technology, East China University of Science and Technology, Shanghai, 200237, China

年份：2025

外文期刊名：SSRN

收录：EI(收录号：20250395118)

语种：英文

外文关键词：Air purification - Aluminum oxide - Catalyst activity - Catalyst supports - Formaldehyde - Nitrogen compounds - Oxidation - Oxygen - Oxygen vacancies - Reaction intermediates - Silver - Silver compounds - Temperature

摘要：Catalytic removal of trace formaldehyde at low temperatures is of significant research interests for indoor air purification. This study developed a silver-based catalyst on a commercial alumina support (K-Ag/La-CeO2/Al2O3) by leveraging metal-support interaction and oxygen vacancy theory, and elucidated the activation sites and the reaction pathway for formaldehyde oxidation. FT-IR confirmed abundant surface hydroxyl groups; XPS revealed the strong metal-support interactions between Ag and the CeO2 surface, which unexpectedly increased Ag+ and Ce4+ contents during H2 reduction at the expense of positively charged silver clusters (Ag+n). UV-Vis spectroscopy and in situ DRIFTS demonstrated that Ag+n species on oxygen vacancy-enriched CeO2 surface oxidized formaldehyde more readily than metallic Ag. Key intermediates including dioxymethylene (DOM), formate, and CO were detected during formaldehyde oxidation, establishing the reaction pathway as HCHO → DOM→ HCOO* → CO → CO2, identical to the pathway observed with noble metal-based catalysts. The oxidation process was governed by the Mars-Van Krevelen mechanism, facilitated by Ag+n sites and lattice oxygen mobility. This work highlighted that maintaining Ag+n as the primary active species and ensuring high oxygen vacancy concentrations is critical for efficient at low temperature formaldehyde oxidation over silver-based catalysts. ? 2025, The Authors. All rights reserved.