Two-Dimensional Earth-Abundant Transition Metal Oxides Nanomaterials: Synthesis and Application in Electrochemical Oxygen Evolution Reaction.

Development of a universal synthetic strategy for two-dimensional (2D) Earth-abundant transition metal oxides nanomaterials is highly vital toward numerous electrochemical applications. Herein, a facile and general synthesis of highly ordered two-dimensional metal oxides nanomaterials includes Co3O4, NiO, CuO, and Fe3O4 nanosheets as an electrocatalyst for oxygen evolution reaction (OER) is demonstrated. Among the synthesized 2D transition metal oxides, the Co3O4 nanosheet exhibits smallest overpotential (η) of ∼384.0 mV at a current density of 10.0 mA cm-2 and Tafel slope of ∼52.0 mV dec-1, highest mass activity of ∼112.3 A g-1 at the overpotential of ∼384.0 mV, and high turn over frequency (TOF) of 0.099 s-1, which is relatively favorable with state-of-the-art RuO2 catalyst. The present synthetic approach may unlock a brand new pathway to prepare shape-controlled Earth-abundant transition metal oxides nanomaterials for electrocatalytic OER.