First-principles insight into the electronic structure, hydration ability and proton conduction of Gd and Y co-doped BaZrO3 proton conductors.

BaZrO 3 -based oxides have attracted attention due to their intrinsic properties that allow protons to traverse. To accelerate proton conduction, a novel BaZr 0.5 Gd 0.25 Y 0.25 O 3 (BZGY) material is proposed as the electrolyte of proton ceramic fuel cells (PCFCs). The electronic structure, synergistic effect and proton transport mechanism of Gd and Y co-doped BaZrO 3 are theoretically studied. Y-doping and Gd-doping promote the formation of oxygen vacancies and the entry of H 2 O molecules into the structure and binding to oxygen vacancies, respectively. The co-doping of Y and Gd promotes the hydration process and increases the proton concentration. The binding of Gd or Y to the oxygen vacancy around the acceptor inhibits proton trapping. BZGY shows rapid and long-distance transport of protons. BZGY has obtained high proton concentrations and mobility, which fully support its potential application in next-generation PCFCs. The synergistic effects of Gd and Y co-doped BaZrO 3 provide important theoretical significance for the study of proton electrolytes. [ABSTRACT FROM AUTHOR]