Microwave-assisted rapid synthesis and activation of ultrathin trimetal–organic framework nanosheets for efficient electrocatalytic oxygen evolution

Ultrathin metal–organic frameworks (MOFs) nanosheets have been considered as one of promising electrocatalysts for oxygen evolution reaction due to their unique structures. However, the preparation process is subject to the low-yield exfoliation and time-consuming synthetic methods. And it still requires to be explored to develop an efficient strategy for regulation of surface electronic states of MOFs to enhance their electrocatalytic activities. Herein, we report a facile microwave-assisted synthesis of NiCoFe-based trimetallic metal-organic framework (MOF) nanosheets, which can achieve simultaneously rapid synthesis and activation of MOF for OER. The as-prepared Ni4Co4Fe2-MOF nanosheets exhibit excellent OER activity and electrochemical stability, which can deliver a current density of 10 mA cm−2 at a low overpotential of 243 mV with a small Tafel slope of 48.1 mV dec-1. This work provides a facile method for the rapid synthesis of MOF nanosheets and also demonstrates an effective approach for regulating the electronic structure of MOFs for electrocatalysis.