Isolated Pt Atoms Embedded in CuO Nanocatalysts for Selective Oxidation of Ammonia

• Published in: ACS catalysis Vol. 13; no. 21; pp. 14070 - 14079
• Main Authors: Lan, Tianwei, Gao, Min, Hasegawa, Jun-ya, Shen, Yongjie, Qu, Wenqiang, Hu, Qingmin, Deng, Jiang, Cheng, Danhong, Zhang, Dengsong
• Format: Journal Article
• Language: English
• Published: American Chemical Society 03.11.2023
• Subjects: ammonia; selective catalytic oxidation; heterogeneous catalysis; N2 selectivity; single atom
• ISSN: 2155-5435; 2155-5435
• DOI: 10.1021/acscatal.3c02613

Establishing a binary synergy is promising to break the scaling relationship in heterogeneous catalysis. In this study, we created CuO nanocatalysts with isolated Pt atoms to selectively oxidize NH3 to N2, which helps to reduce fine particulate matter air pollution. These nanocatalysts had a reaction rate 30 times higher than CuO catalysts at 160 °C and 30% higher N2 selectivity than Pt catalysts at 99% NH3 conversion. Our experimental and theoretical findings showed that a reaction field separation strategy was responsible for the improved performance. Specifically, isolated Pt atoms facilitated the adsorption/activation of O2 while adjacent Cu atoms facilitated NH3 adsorption/activation. Through operando infrared spectroscopy and theoretical calculations, we found that the weaker adsorption of the NO2 intermediate on Cu sites was crucial for better performance. This research sets the foundation for developing high-performance heterogeneous catalysts.