Nanoscale alloying in metal nanoparticle catalysts play a critical role in catalytic and electrocatalytic synergies for many reactions, understanding of which constitutes an important front of research and development in sustainable energy and environment. The highly-dynamic nature of nanoalloys in catalytic and electrocatalytic reactions requires probing the detailed surface sites and nanocrystal structures of the catalysts through characterizations of the catalysts as prepared and under the reaction conditions or during the reactions. This presentation will discuss some of the recent results of ex-situ and in-situ/operando studies of several types of nanoalloy (nanoparticles and nanowires) catalysts in catalytic oxidation of carbon monoxide and hydrocarbons, and in electrocatalytic oxygen reduction and alcohol oxidation reactions. Examples will highlight the use of diffuse reflectance infrared Fourier transform spectroscopy and high energy x-ray diffraction coupled with atomic pair distribution function analysis for in situ/operando characterizations of platinum and palladium based binary and ternary nanoalloys, core-shell nanoparticles and nanowires in the reactions. Insights into the correlation of the catalytic or electrocatalytic synergies with the size, shape, composition, and surface sites will be also discussed.
