Anchoring Ni doped Mn3O4 on Bimetallic CoFe Layered Double Hydroxide for Efficient Electrocatalytic Oxygen Evolution Reaction

Abstract

The advancement of highly effective electrocatalysts for water electrolysis applications has become a prominent topic of interest. In particular, the oxygen evolution reaction (OER) has garnered considerable attention due to the substantial overpotential associated with the intricate four-electron transfer coupled reaction. Upgrading economic water splitting technique requires evolution of two-dimensional, inexpensive, robust electrocatalyst for oxygen evolution reactions (OERS). In this study, a low temperature single-step co-precipitation formation method is used for manufacturing of a 2D heterostructure Ni doped Mn3O4/CoFe layered double hydroxide (LDH)merged composite on a GCE substrate. The as-prepared Ni doped Mn3O4 /NiFe LDH (30 wt%) electrocatalyst shows an excellent OER performance with current of 10 mA/cm2 , with the lowest reported overpotential of 335 mV as well as Tafel slope 38 mV/dec in 1 M KOH electrolyte. A prolonged oxygen evolution was carried out over several hours at an applied potential of 1.56 V (versus RHE) to examine the stability of active CoFe LDH/Ni-Mn3O4 of 30 wt%. OER activities of formed catalyst are excellent even to surpass that of RuO2 OER electrocatalyst. The synergetic effect of CoFe LDHs and Ni doped Mn3O4 is the reason of its excellent OER activity. Outstanding corrosion resistance of the electrocatalyst in alkaline medium is due to inherently present, cheap Ni metal, and the enhancement of the electronic conductivity of the electrocatalyst is due to active edge sites of Ni-doped Mn3O4 /CoFe LDH composite sheets.