Abstract
Photoinduced splitting of water using photocatalysts in the form of nanoparticles is a promising and simple way to produce environmentally friendly hydrogen. In this paper, we investigate the potential of modified barium titanate (BaTiO3), an inexpensive perovskite oxide obtained from precursors widely distributed on earth, to develop effective electrocatalysts for water oxidation using first-principles calculations. It has been shown that the BaTiO3(001) surface terminated with TiO2 is more promising in terms of its use as a catalyst. After replacing Ti with Rh, the dopant ion can take over part of the electron density from neighboring oxygen ions. As a result, during the oxidation reaction of water, rhodium ions can be in an intermediate oxidation state between 3+ and 4+. This affects the adsorption energy of the reaction intermediates on the surface of the catalyst, reducing the excess potential.