Tailoring catalytic properties of V2O3 to propane dehydrogenation through single-atom doping: A DFT study

Abstract

Vanadium-oxide-based catalysts have recently been found very promising for the catalytic dehydrogenation of propane. In this work, self-consistent density functional theory calculations have been performed to examine how the electronic structure of the V2O3(0001) surface is modified by single-atom doping and how the catalytic properties can be tailored to propane dehydrogenation. The structural stability of single-atom-doped V2O3(0001) surfaces is assessed by comparing the adsorption energies of single atoms with the cohesive energies of bulk metals. A weak Lewis acid-base interaction is found to occur on the pristine surface, which can be strengthened and weakened by substitution of single atoms for V and O, respectively. On these two types of oxide surfaces, single atoms act as promoters and active sites. The first dehydrogenation step is identified as the rate-limiting step by microkinetic analysis. On all the single-atom-doped surfaces, the activation energy for water formation is higher than that for hydrogen recombination, implying that reduction of the oxide surfaces is difficult to take place during the course of the reaction. If a compromise between the catalytic activity and catalyst selectivity is made, Mn1-V2O3 is suggested to be a good candidate as the catalyst for propane dehydrogenation.