First-principal study of proton transfer in metal oxide perovskite

The mechanism of proton conduction of defect-free perovskite $\rm LaScO_3$ was investigated by ab initio molecular dynamics. The effects of the initial location and speed of a proton, the electric field, and the temperature of the system on the behavior of a proton in metal oxides of the perovskite type are considered. It is shown that the temperature of the system is the main factor affecting the speed of proton movement. The Arrhenius temperature behavior of proton conduction is found. In the absence of oxygen vacancies, the direction of proton movement in a crystal with a perovskite structure is determined by its interaction with lattice phonons; i.e., proton migration through metal-oxide perovskite has a polaronic character. Better understanding of the nature of proton migration along the perfect perovskite is one of the ways to improve the characteristics of clean energy devices.