Unraveling the Positive Role of WO on Supported Vanadium Catalysts for NO Reduction by Operando Spectroscopy

Overview

Journal ACS Omega

Publisher American Chemical Society

Date 2025 Jan 20

PMID 39829485

Authors

Zhihui Lv

Guangyan Xu

Yingjie Wang

Yunbo Yu

Hong He

Affiliations

Soon will be listed here.

Abstract

Selective catalytic reduction of nitrogen oxides (NO ) by ammonia (NH-SCR) over supported vanadium catalysts is a commercial technology for NO abatement in combustion exhaust. The addition of tungsten oxide (WO) significantly enhances the performance of supported vanadium catalysts (VO/TiO), but the mechanism underlying this enhancement remains controversial. In this study, we employed combined operando spectroscopy (DRIFTS-UV-vis-MS) to investigate the dynamic state of active sites (acid sites and redox sites) on VO-WO/TiO during the NH-SCR reaction. Our findings confirmed that WO occupied the TiO surface and reduced the available surface sites for VO anchoring, thus promoting the agglomeration of vanadia species. This structural effect significantly improved the reducibility of VO on VO-WO/TiO catalysts, consequently enhancing the efficiency for NO reduction. The heightened reducibility rendered the reoxidation of vanadia species a rate-limiting step, resulting in the presence of vanadia species in a lower oxidation state (V) during the NH-SCR reaction.

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