Structure evolution and durability of Metal-Nitrogen-Carbon (M = Co, Ru, Rh, Pd, Ir) based oxygen evolution reaction electrocatalyst: A theoretical study.

[Display omitted] • The effect of structure evolution under working condition of MNC electrocatalysts on the OER activity and stability has been studied with the DFT method. • This work conducted a comprehensive evaluation method for MNC electrocatalysts by taking ΔG *OH as the screening criterion for OER activity and ΔE b of electrocatalysts under working conditions as the stability descriptor. • The stability of MNC electrocatalysts under working conditions, including high temperature, dynamic condition, local electric field and strong specific adsorption has been studied in detail. Developing low-cost, high activity and stability oxygen evolution reaction (OER) catalysts is significantly important but still challenging for water electrolyzers. In this work, we calculated the OER activity and stability of Metal-Nitrogen-Carbon (MNC, M = Co, Ru, Rh, Pd, Ir) based electrocatalyst with different structures (MN 4 C 8 , MN 4 C 10 , MN 4 C 12) using density functional theory (DFT) method. These electrocatalysts were divided into three groups based on the value of ΔG *OH , that is ΔG *OH > 1.53 eV (PdN 4 C 8 , PdN 4 C 10 , PdN 4 C 12), ΔG *OH < 1.23 eV (RuN 4 C 8 , RuN 4 C 10 , RuN 4 C 12 , CoN 4 C 8 , CoN 4 C 10) and 1.23 eV < ΔG *OH < 1.53 eV (RhN 4 C 8 , RhN 4 C 10 , RhN 4 C 12 , IrN 4 C 8 , IrN 4 C 10 , IrN 4 C 12 , CoN 4 C 12), and ΔG *OH determine whether the structure evolution will appear. The results proved that MNC (M = Rh, Ir) with 1.23 eV < ΔG *OH < 1.53 eV shows higher OER activity due to moderate binding energy between reaction intermediates and MNC. Furthermore, these catalysts could maintain M N C structure without further oxidation and structural evolution under working conditions (high temperature, dynamic condition, local electric field and strong specific adsorption), therefore show excellent stability. However, MNC electrocatalyst with ΔG *OH > 1.53 eV or ΔG *OH < 1.23 eV revealed less stability under working conditions, due to their low intrinsic stability or structural evolution under working conditions, respectively. In conclusion, we proposed a comprehensive evaluation method for MNC electrocatalysts by taking ΔG *OH as the screening criterion for OER activity and stability, as well as ΔE b under working condition as descriptor of stability. This is of great significance for the design and screening of ORR, OER and HER electrocatalysts under working conditions. [ABSTRACT FROM AUTHOR]