Abstract
The ubiquitous presence of moisture usually shows adverse effects on industrial catalysis. Herein, a concept of engineering entropy to design water-resistant oxide catalysts is proposed. The C(3)H(6) oxidation by spinel ACr(2)O(4) (A=Ni, Mg, Cu, Zn, Co) catalysts is selected as a model. Through DFT calculation, the adsorption energy of C(3)H(6), the dissociation energy of molecular H(2)O on the oxide surface, and the formation energy of oxygen vacancy all suggest better performance induced by higher configurational entropy. Indeed, (Ni(0.2)Mg(0.2)Cu(0.2)Zn(0.2)Co(0.2))Cr(2)O(4) experimentally show excellent water resistance (>100 h) in C(3)H(6) oxidation, while in sharp contrast binary oxides (e.g., NiCr(2)O(4), CoCr(2)O(4)) are deactivated in 20 h. H(2)O-TPD, in-situ Raman, and in-situ FTIR all confirm the low H(2)O adsorption energy and strong hydrothermal stability of high entropy oxide, which is attributed to their lower Gibbs free energy. This work may inspire the rational design of water-resistant catalysts.