Computational Studies of Pure and Mo-Doped Pt Nanocatalysts: Effects of Size, Structure, and Composition

Our general motivation is to explore and characterize the catalytic functionality of pure and alloy metal nanocatalysts as a function of their size, structure, composition, and support. The catalysts of primary interest are those relevant to reforming of glycerol and formic acid (e.g., into hydrogen). Pt is one of the best catalysts for these and many other catalytic transformations.

It has been found that adding Mo to Pt further improves its catalytic functionality in glycerol reforming, water-gas shift reaction, electrooxidation of hydrogen [1-2], and other reactions. The specific goal of this study is to explore the structural and electronic properties of pure and mixed Pt and Mo nanocatalysts as defined by their size and composition, and to characterize the role of these in shaping the chemical/catalytic activity of the nanocatalysts.

We are particularly interested in understanding the role of admixing Mo to Pt and in characterizing the mechanism(s) through which this admixing affects the catalytic efficiency of Pt at the nanoscale. As a paradigmatic reaction relevant and important in the context of glycerol and formic acid reforming, as well as many other catalytic processes, we consider adsorption of CO, which may have a poisoning effect. One of the questions we address is: Does adding Mo to Pt nanocatalysts reduce the CO poisoning effect and, if yes, how?

This material is based upon work supported as part of the Institute for Atom-efficient Chemical Transformations (IACT), an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences.

[1] E. I Santiago et al., Electrochim. Acta, (2003) 48, 3527-3534.

[2] S. Mukerjee et al., J. Electrochem. Soc., (2004) 151, A1094-A1103.