Controlled Synthesis of P‐NCO@Co‐MOF on Ni Foam for Boosting Oxygen Evolution Reaction Activity

ABSTRACT Metal–organic frameworks (MOFs) have won widespread focus and research due to their outstanding activity during the electrocatalytic oxygen evolution reaction (OER), attributed to their varied structural characteristics, highly ordered pore architecture, and abundant active sites. In this study, P‐NCO@Co‐MOF is presented as an efficient OER catalyst, mounted on a nickel foam substrate through a hydrothermal combined annealing phosphating method. The prepared ultrathin two‐dimensional sheet‐like structures, developed on Co‐MOF arrays, exhibit highly exposed active regions and numerous metal center areas, which are conducive to enhanced electrocatalytic OER activity. P‐NCO@Co‐MOF demonstrates remarkable OER activity, characterized by an overpotential of merely 239 mV at 10 mA cm −2 in 1.0 M of KOH solution and a low Tafel slope of 59 mV dec −1 . Additionally, P‐NCO@Co‐MOF exhibits robust stability, evidenced by negligible chronoamperometric decay after 100 h of continuous operation. The factor contributing to the excellent OER activity is the synergistic coupling of MOF arrays with ultrathin nanosheets, which enhances charge transfer kinetics and electrical conductivity. This study offers a degree of reference into the development of ultraefficient MOF structure–based OER catalysts.