title: Atomic-Scale Observations of Catalyst Structures under Reaction Conditions and during Catalysis.
abstract: Heterogeneous catalysis is a chemical process performed at a solid-gas or solid-liquid interface. Direct participation of catalyst atoms in this chemical process determines the significance of the surface structure of a catalyst in a fundamental understanding of such a chemical process at a molecular level. High-pressure scanning tunneling microscopy (HP-STM) and environmental transmission electron microscopy (ETEM) have been used to observe catalyst structure in the last few decades. In this review, instrumentation for the two in situ/operando techniques and scientific findings on catalyst structures under reaction conditions and during catalysis are discussed with the following objectives: (1) to present the fundamental aspects of in situ/operando studies of catalysts; (2) to interpret the observed restructurings of catalyst and evolution of catalyst structures; (3) to explore how HP-STM and ETEM can be synergistically used to reveal structural details under reaction conditions and during catalysis; and (4) to discuss the future challenges and prospects of atomic-scale observation of catalysts in understanding of heterogeneous catalysis. This Review focuses on the development of HP-STM and ETEM, the in situ/operando characterizations of catalyst structures with them, and the integration of the two structural analytical techniques for fundamentally understanding catalysis.
authors.affiliation: Department of Chemical and Petroleum Engineering, University of Kansas , Lawrence, Kansas 66045, United States.|Department of Chemistry, University of Kansas , Lawrence, Kansas 66045, United States.
authors.forename: Franklin Feng
authors.initials: FF
authors.lastname: Tao
authors.affiliation: School of Engineering of Matter, Transport and Energy, Arizona State University , Tempe, Arizona 85287, United States.
authors.forename: Peter A
authors.initials: PA
authors.lastname: Crozier