Redox properties of transition metal oxides NiO₂ and CoO₂ from a defect perspective

The splitting of water is considered the cleanest method for harvesting renewable energy, offering both environmental and economic benefits. Here, I will present our study on the redox properties of two layered transition metal oxides NiO₂ and CoO₂. There is a consensus that an open d-shell transition-metal atom in a specific oxidation state is desirable for favorable catalysis. The oxidation state of transition-metal can be tuned by using alkali metals, thereby restructuring the electronic properties of these layered materials to make them favorable for catalysis. Our study employs the density functional HSE06 and r2SCAN+rVV10+U to search for the polaron that can produce the favorable e_g¹ configuration.