Insights into the origin of super-high oxygen evolution potential of Cu doped SnO2 anodes: A theoretical study

Abstract SnO 2 based anodes have been recognized as the most promising anodes for wastewater treatment due to the high oxygen evolution potential, high current efficiency and low cost. Herein, using large-scale screening-based density functional theory, we systemically investigate the origin of super-high oxygen evolution potential of Cu doped SnO 2 anodes. We find that the low binding energy of OH * on (1 1 0) plane of Cu doped SnO 2 anodes leads to the high onset potential for oxygen evolution. Detailed calculations of bond configurations and valence electron numbers reveal that the weak chemical absorption of OH * contribute to the low binding energy. The theoretical onset potential of oxygen evolution of 2.639 V (vs RHE) obtained from Free-energy diagram for OERs agrees well with the experimental value of ∼2.7 V (vs RHE).