Ion‐change promoting Co nanoparticles@N‐doped carbon framework on Co2SiO4/rGO support forming “double‐triple‐biscuit” structure boosts oxygen evolution reaction

Abstract

AbstractExploring economic and high‐performance electrocatalysts to decrease the overpotential of oxygen evolution reaction (OER) and facilitate its reaction kinetics is a frontier subject in line with green energy. Herein, metal‐organic framework (MOF)‐derived Co nanoparticles@N‐doped carbon (Co NPs@N,C) is rationally designed on sandwich‐like cobalt silicate/reduced graphene oxide (Co2SiO4/rGO) support to acquire Co NPs@N,C/Co2SiO4/rGO “double‐triple‐biscuit”‐like structure as enhanced OER electrocatalysts. Co NPs@N,C on Co2SiO4/rGO support optimizes its geometric architecture and introduces new active sites. The “double‐triple‐biscuit”‐like Co NPs@N,C/Co2SiO4/rGO structure achieves excellent OER ability compared with the existing materials based on transition metal silicates (TMSs). The overpotential of 278 mV is achieved at the current density of 10 mA cm−2, and it is prominently higher than Co2SiO4/rGO support (390 mV). This excellent OER activity is rooted in its structural peculiarity, enabling efficient ion and electron transport. Co NPs@N,C are highly dispersed on the Co2SiO4/rGO support, increasing the active sites and avoiding self‐aggregation of Co NPs in the OER process. This work combines the advantages of Co2SiO4/rGO support with the triple biscuits' structure and MOF to implement the preparation of boosted Co NPs@N,C/Co2SiO4/rGO, and it opens a new avenue for designing novel architectures to promote the OER activity of TMSs.