In Situ Microscopy and Spectroscopy Applied to Surfaces at Work

Abstract

The present review discusses the current state of the art microscopic and spectroscopic characterization techniques available to study surfaces and interfaces under working conditions. Microscopic techniques such as environmental transmission electron microscopy and in situ transmission electron microscopy are first discussed showing their applications in the field of nanomaterials and catalysis. Next sum frequency generation vibrational spectroscopy is discussed, giving probing examples of surface studies in gaseous conditions. Synchrotron based X‐ray techniques are also examined with a specific focus on ambient pressure X‐ray photoelectron and absorption techniques such as near and extended X‐ray absorption fine structure. Each of the techniques is evaluated, whilst the pros and cons are discussed in term of surface sensitivity, spatial resolution and/or time resolution. The second part of the articles is articulated around the future of in situ characterization, giving examples of the probable development of the discussed techniques as well as an introduction of emerging tools such as scanning transmission X‐ray microscopy, ptychography, and X‐ray photon correlation spectroscopy.

Product distribution change in the early stages of carbon monoxide hydrogenation over cobalt magnesium Fischer-Tropsch catalyst

“…In parallel, the use of this method combined with in situ characterization such as sum frequency generation spectroscopy, x-ray adsorption, x-ray emission, and photoelectron spectroscopies [18] will help define the key factors at an atomic level which influence the kinetics of reactions as well as the restructuring occurring in nanomaterials often used in heterogeneous catalysis.…”

Bifunctional Metal Nanocrystals for Catalyzing and Reporting on Chemical Reactions

“…[22] To obtain kinetic information from the intensities of peaks in the SERS spectra, they introduced another molecular probe, such as 2-naphthalenethiol (2-NT), to the surfaces of Au as an internal reference to allow relative quantification. It was argued that the adsorption of 2-NT on the Au surface should not be affected by NaBH 4 . In a typical study, a glass substrate covered by the binary mixture of nanoparticles was immersed in a solution containing 4-NTP and 2-NT for 1 h before SERS measurements.…”

“…To this end, infrared reflection-absorption spectroscopy (IRAS) and sum frequency generation (SFG) spectroscopy have been reported. [4,5] Unfortunately, both techniques inherit intrinsic problems that include low detection sensitivity, limited range of wavenumbers, interference from the bulk phase, and inability to detect some vibrational modes because of surface-selection rules.…”

Development and Elucidation of Superior Turnover Rates and Selectivity of Supported Molecular Catalysts

“…However, utilizations of characterization techniques, especially under reaction conditions, further facilitates the discovery of information about reaction mechanisms, including the active sites, intermediates, etc. The development and use of in situ characterization techniques for catalysis and surface chemistry applications have been a focus of research for the last two decades . We will provide two case studies of such in the section.…”