Tailoring the Local Environment of Platinum in Single‐Atom Pt 1 /CeO 2 Catalysts for Robust Low‐Temperature CO Oxidation

• Published in: Angewandte Chemie Vol. 133; no. 50; pp. 26258 - 26266
• Main Authors: Jiang, Dong, Yao, Yonggang, Li, Tangyuan, Wan, Gang, Pereira‐Hernández, Xavier Isidro, Lu, Yubing, Tian, Jinshu, Khivantsev, Konstantin, Engelhard, Mark H., Sun, Chengjun, García‐Vargas, Carlos E., Hoffman, Adam S., Bare, Simon R., Datye, Abhaya K., Hu, Liangbing, Wang, Yong
• Format: Journal Article
• Language: English
• Published: Germany Wiley Blackwell (John Wiley & Sons) 06.12.2021
• ISSN: 0044-8249; 1521-3757
• DOI: 10.1002/ange.202108585

Abstract A single‐atom Pt 1 /CeO 2 catalyst formed by atom trapping (AT, 800 °C in air) shows excellent thermal stability but is inactive for CO oxidation at low temperatures owing to over‐stabilization of Pt 2+ in a highly symmetric square‐planar Pt 1 O 4 coordination environment. Reductive activation to form Pt nanoparticles (NPs) results in enhanced activity; however, the NPs are easily oxidized, leading to drastic activity loss. Herein we show that tailoring the local environment of isolated Pt 2+ by thermal‐shock (TS) synthesis leads to a highly active and thermally stable Pt 1 /CeO 2 catalyst. Ultrafast shockwaves (>1200 °C) in an inert atmosphere induced surface reconstruction of CeO 2 to generate Pt single atoms in an asymmetric Pt 1 O 4 configuration. Owing to this unique coordination, Pt 1 δ+ in a partially reduced state dynamically evolves during CO oxidation, resulting in exceptional low‐temperature performance. CO oxidation reactivity on the Pt 1 /CeO 2 _TS catalyst was retained under oxidizing conditions.