Kelsey A. Stoerzinger, Wesley T. Hong, Gisele Azimi, Livia Giordano, Yueh-Lin Lee, Ethan J. Crumlin, Michael D. Biegalski, Hendrik Bluhm, Kripa K. Varanasi, and Yang Shao-Horn

DOI: 10.1021/acs.jpcc.5b06621

Oxides are instrumental to applications such as catalysis, sensing, and wetting, where the reactivity with water can greatly influence their functionalities. We find that the coverage of hydroxyls (*OH) measured at fixed relative humidity trends with the electron-donor (basic) character of wetted perovskite oxide surfaces. Using ambient pressure X‑ray photoelectron spectroscopy, we report that the affinity toward hydroxylation, coincident with strong adsorption energies calculated for dissociated water and hydroxyl groups, leads to strong H bonding that is favorable for wetting while detrimental to catalysis of the oxygen reduction reaction (ORR). Our findings provide novel insights into the coupling between wetting and catalytic activity and suggest that catalyst hydrophobicity should be considered in aqueous oxygen electrocatalysis.

Related Links:

Reactivity of Perovskites with Water: Role of Hydroxylation in Wetting and Implications for Oxygen Electrocatalysis (Physical Chemistry)

How to look for a few good catalysts (MIT News)

Professor Yang Shao-Horn