Breaking the scaling relationship <i>via</i> dual metal doping in a cobalt spinel for the OER: a computational prediction
Yikun Kang, Feiran Zhang, Bowen Liu, Yuanqing Sun, Xiao Zhang, Weiyu Song, Yuechang Wei, Zhen Zhao, Jian Liu
Abstract
with five-fold coordination (Co3+5f) was identified as the active site. A total of 23 metal doping types were employed based on the reconstructed surface. We showed that the OER process with lattice oxygen participating can lead to favorable thermodynamics by the doping of early transition metals, and the O-O coupling of surface lattice oxygen can be facilitated kinetically by dual doping with Zn. Considering both thermodynamics and kinetics, the dual doping of Zn-Cr exhibits theoretical OER activity beyond the conventional AEM limitations and is suggested to be a candidate with enhanced OER performance. Moreover, we demonstrated that the dual doping with Zn enhances metal-oxygen covalency, where the moderate activity of the surface lattice oxygen is required for feasible O-O coupling kinetics while retaining favorable thermodynamic propensity.