A hierarchical CoMoO4 nanoparticle decorated nanoplate array as an electrocatalyst toward improved alkaline oxygen evolution reaction

Abstract

Highly efficient noble metal-free water oxidation electrocatalysts play a key role in water splitting devices for large-scale hydrogen production. In this communication, we report the surface engineering of a CoMoO₄ nanoplate array on nickel foam (CoMoO₄ NPAs/NF) by CoMoO₄ nanoparticle decoration. The hierarchical structure of the as-formed CoMoO₄ NP@PAs/NF (CoMoO₄ nanoparticle coated nanoplate array on Ni foam) guarantees the exposure of more catalytically active sites with a much larger electrochemically active surface area, leading to improved catalytic activity for the oxygen evolution reaction (OER) in alkaline media. In 1 M KOH, it needs a low overpotential of 317 mV to attain 100 mA cm⁻², 72 mV less than that for CoMoO₄ NPAs/NF. Moreover, this system is also durable with a twice higher turnover frequency (TOF) value of 0.41 s⁻¹ at 400 mV overpotential compared with CoMoO₄ NPAs/NF.