High-loading single Pt atom sites [Pt-O(OH) x ] catalyze the CO PROX reaction with high activity and selectivity at mild conditions

Sufeng Cao; Yanyan Zhao; Sungsik Lee; Shize Yang; Jilei Liu; Georgios Giannakakis; Mengwei Li; Mengyao Ouyang; Dunwei Wang; E Charles H Sykes; Maria Flytzani-Stephanopoulos

doi:10.1126/sciadv.aba3809

High-loading single Pt atom sites [Pt-O(OH) _x ] catalyze the CO PROX reaction with high activity and selectivity at mild conditions

Sci Adv. 2020 Jun 17;6(25):eaba3809. doi: 10.1126/sciadv.aba3809. eCollection 2020 Jun.

Authors

Affiliations

¹ Department of Chemical and Biological Engineering, Tufts University, Medford, MA 02155, USA.
² Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, MA 02467, USA.
³ X-ray Science Division, Argonne National Laboratory, Lemont, IL 60439, USA.
⁴ Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973, USA.
⁵ Department of Chemistry, Tufts University, 62 Talbot Avenue, Medford, MA 02155, USA.

Abstract

The preferential oxidation of CO (PROX) in hydrogen-rich fuel gas streams is an attractive option to remove CO while effectively conserving energy and H₂. However, high CO conversion with concomitant high selectivity to CO₂ but not H₂O is challenging. Here, we report the synthesis of high-loading single Pt atom (2.0 weight %) catalysts with oxygen-bonded alkaline ions that stabilize the cationic Pt. The synthesis is performed in aqueous solution and achieves high Pt atom loadings in a single-step incipient wetness impregnation of alumina or silica. Promisingly, these catalysts have high CO PROX selectivity even at high CO conversion (~99.8% conversion, 70% selectivity at 110°C) and good stability under reaction conditions. These findings pave the way for the design of highly efficient single-atom catalysts, elucidate the role of ─OH species in CO oxidation, and confirm the absence of a support effect for our case.

Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).