In situ Formed Co(TCNQ)2 Metal‐Organic Framework Array as a High‐Efficiency Catalyst for Oxygen Evolution Reactions

Abstract Energy conversion and storage systems such as water splitting devices and metal‐air batteries need excellent and energy‐efficiency oxygen evolution reaction (OER) catalysts. This work reports the in situ development of sawtooth‐like Co(TCNQ) 2 (TCNQ=tetracyanoquinodimethane) metal–organic framework array on Co foil (Co(TCNQ) 2 /Co) by means of a solution immersion method at room temperature. As an oxygen‐evolving catalyst, the resulting Co(TCNQ) 2 /Co demonstrates superior OER activity with overpotential of 310 mV to drive a geometrical catalytic current density of 15 mA cm −2 in 1.0 M KOH. Notably, it also shows good long‐term electrochemical durability with its activity being retained for at least 20 h and achieves a high turnover frequency of 0.66 mol O 2 s −1 at overpotential of 380 mV.