First-principles study of oxygen evolution reaction on Ni3Fe-layered double hydroxides surface with different oxygen coverage

The oxygen evolution reaction performance was studied in the different oxygen coverage on the 110 surface of Ni3Fe-layered double hydroxides by the first-principles. The OER activities on three O covered surfaces were compared with clean surface. The three different O covered surfaces included (i)1/4 monolayer O covered, (ii) 1/2 monolayer O covered, (iii) 3/4 monolayer O covered surface. The computed overpotential (η) on the four cases followed the order: 1/4 monolayer < clean < 1/2 monolayer < 3/4 monolayer. And the overpotential of the active site has the following order 1/4 monolayer Fe < 1/4 monolayer Ni. By calculating the partial density of states and Bader charge on the O covered surface, it was found that 1/4 monolayer O covered surface combined with the formation OH easily. Based on the above analysis, the 1/4 monolayer O covered Ni3Fe-layered double hydroxides surface exhibited better OER catalytic performance than that of the clean surface in the OER cycle.