Recent advances of single-atom catalysts in the selective catalytic reduction of NO by CO

Abstract

This review summarizes the advances and applications of single-atom catalysts (SACs) in the selective catalytic reduction of NO by CO (CO-SCR). Various types of SACs are discussed, including conventional SACs, negatively charged SACs, dual-atom catalysts, singly dispersed bimetallic sites catalysts, single-atom alloy catalysts, and single-atom-cluster/nanoparticle catalysts. The unique properties of each type of catalyst and their catalytic performance in CO-SCR are explored. SACs enhance the adsorption and activation of NO through synergistic interactions with the support, thereby improving catalytic activity and optimizing the reaction pathway. Furthermore, tuning atomic structure, coordination environment, and metal-support interactions can further enhance the catalytic performance. Despite showing excellent catalytic activity under laboratory conditions, SACs still face challenges in industrial applications, such as catalyst stability, scalability and resistance to poisoning. Future research will focus on improving SAC stability, increasing the density of active sites, and enhancing resistance to deactivation. Combining advanced synthesis methods, large-scale production techniques, and in-depth structural characterization will be crucial for the industrial application of SACs in environmental and energy-related fields.

Keywords

Single-atom catalysts / selective catalytic reduction / NO reduction with CO / catalytic activity

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