Towards understanding structural disorder in oxide electrocatalyts through first-principles calculations

Intentional amorphization or amorphization due to electrochemical cycling is a broadly observed phenomena in electrocatalysis for sustainable fuel production. Transition metal oxides are an ideal platform in elucidating structure-composition-catalysis design principles, particularly from the perspective of amorphous systems, which are prominent but not well understood systems. A central question is whether structural disorder simply gives rise to more electrochemically accessible active sites or whether novel active sites are present. We focus on the perovskite tungsten oxide, a model system for understanding correlations among geometric, electronic, and active site structure and as an alternate or complementary material to electrocatalysts based on precious metals. Turning to first-principles calculations and machine-learned interatomic potentials, we discuss computational aspects surrounding the generation of amorphous structural models for transition metal oxides and their electronic properties, compare and contrast the crystalline and amorphous phases in the bulk and at the surface, and look towards methods for sampling active sites with microscopic models.