Structural Evolution of Anatase-Supported Platinum Nanoclusters into a Platinum-Titanium Intermetallic Containing Platinum Single Atoms for Enhanced Catalytic CO Oxidation

Wenxue He; Xu Zhang; Kun Zheng; Chuanqiang Wu; Ya Pan; Hongmei Li; Liuxin Xu; Ruichao Xu; Wei Chen; Yi Liu; Chao Wang; Zhihu Sun; Shiqiang Wei

doi:10.1002/anie.202213365

Structural Evolution of Anatase-Supported Platinum Nanoclusters into a Platinum-Titanium Intermetallic Containing Platinum Single Atoms for Enhanced Catalytic CO Oxidation

Angew Chem Int Ed Engl. 2023 Jan 9;62(2):e202213365. doi: 10.1002/anie.202213365. Epub 2022 Dec 7.

Authors

Wenxue He¹, Xu Zhang², Kun Zheng², Chuanqiang Wu³, Ya Pan¹, Hongmei Li¹, Liuxin Xu¹, Ruichao Xu¹, Wei Chen¹, Yi Liu¹, Chao Wang¹, Zhihu Sun¹, Shiqiang Wei¹

Affiliations

¹ National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230029, P. R. China.
² Beijing Key Lab of Microstructure and Properties of Solids, Faculty of Materials and Manufacturing, Beijing University of Technology, Beijing, 100124, China.
³ Information Materials and Intelligent Sensing Laboratory of Anhui Province, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Institutes of Physical Science and Information Technology, Anhui University, Hefei, 230601, China.

PMID: 36396598
DOI: 10.1002/anie.202213365

Abstract

Strong metal-support interactions characteristic of the encapsulation of metal particles by oxide overlayers have been widely observed on large metal nanoparticles, but scarcely occur on small nanoclusters (<2 nm) for which the metal-support interactions remain elusive. Herein, we study the structural evolution of Pt nanoclusters (1.5 nm) supported on anatase TiO₂ upon high-temperature H₂ reduction. The Pt nanoclusters start to partially evolve into a CsCl-type PtTi intermetallic compound when the reduction temperature reaches 400 °C. Upon 700 °C reduction, the PtTi nanoparticles are exclusively formed and grow epitaxially along the TiO₂ (101) crystal faces. The thermodynamics of the formation of PtTi via migration of reduced Ti atoms into Pt cluster is unraveled by theoretical calculations. The thermally stable PtTi intermetallic compound, with single-atom Pt isolated by Ti, exhibits enhanced catalytic activity and promoted catalytic durability for CO oxidation.

Keywords: CO Oxidation; Intermetallic Compound; Single Atoms; Strong Metal-Support Interactions; Structural Evolution.

Abstract

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