In Situ Synthesis of Ultrathin Co3O4 Nanoflakes Film on Ni Foam with Enhanced Performance for Electrochemical Oxygen Evolution

Herein we present a brand-new and straightforward method for producing ultrathin Co3O4 nanoflakes directly on a Ni foam (NF) substrate, resulting in a Co3O4@NF electrode. An intrinsic cross-linked structure with a flake thickness of about 2.5 nm is created by the anchored ultrathin Co3O4 nanoflakes, and it has the advantages of strong affinity, good conductivity, and a large active surface area. Utilized as an additive-free electrode, the substance works admirably in the oxygen evolution reaction (OER) with a low overpotential of 290 mV at 10 mA cm-2, a small Tafel slope of 61.2 mV dec-1, and great durable stability for long-term operating. In situ EIS further reveals its intrinsic kinetic characteristics for excellent OER catalytic performance. Besides, A well-established electrolyzer can also produce a current density of 290 mA cm-2 at 2 V and has improved long-term stability when using Pt@NF as the cathode and Co3O4@NF as the anode. From a methodological perspective, the suggested procedure may be extremely valuable in the synthesis of other efficient catalytic ultrathin nanoparticles (Nps).