Mingchu Ran, Yi Dong, Xiao Zhang*, Weixian Li, Zhi Wang, Saisai Lin, Yang Yang, Hao Song, Weihong Wu, Shaojun Liu, Yihan Zhu, Chenghang Zheng and Xiang Gao*,
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引用次数: 0
Abstract
NH3 emissions from industrial sources and possibly future energy production constitute a threat to human health because of their toxicity and participation in PM2.5 formation. Ammonia selective catalytic oxidation to N2 (NH3–SCO) is a promising route for NH3 emission control, but the mechanistic origin of achieving high N2 selectivity remains elusive. Here we constructed a highly N2-selective CuO/TiO2 catalyst and proposed a CuOx dimer active site based on the observation of a quadratic dependence of NH3–SCO reaction rate on CuOx loading, ac-STEM, and ab initio thermodynamic analysis. Combining this with the identification of a critical N2H4 intermediate by in situ DRIFTS characterization, a comprehensive N2H4-mediated reaction pathway was proposed by DFT calculations. The high N2 selectivity originated from the preference for NH2 coupling to generate N2H4 over NH2 dehydrogenation on the CuOx dimer active site. This work could pave the way for the rational design of efficient NH3–SCO catalysts.
期刊介绍:
Environmental Science & Technology (ES&T) is a co-sponsored academic and technical magazine by the Hubei Provincial Environmental Protection Bureau and the Hubei Provincial Academy of Environmental Sciences.
Environmental Science & Technology (ES&T) holds the status of Chinese core journals, scientific papers source journals of China, Chinese Science Citation Database source journals, and Chinese Academic Journal Comprehensive Evaluation Database source journals. This publication focuses on the academic field of environmental protection, featuring articles related to environmental protection and technical advancements.