Scalable Production of Nickel Cobaltite Nanoplates using Solution-Processed Inks for OER Electrocatalysis

The large-scale fabrication of non-precious metal oxide electrocatalysts with reasonable control over catalytic active surface sites is critical for oxygen evolution reaction (OER). Herein, we report an industrially scalable, dip-coating method for the fabrication of 3D electrodes using Co and Ni thiolate hybrid inks. The solventless thermolysis of Co hexadecane thiolate in Ni butane thiolate (4:1) mixture results in 2D nanoplates of Ni-Co oxide (NCO) with spinel structure and superparamagnetic nature. The NCO acts as an electrocatalyst exhibiting excellent OER performance in alkaline media with low overpotential values of 310 mV and long-term stability. XPS studies reveal that Ni³⁺ and Co³⁺ species on the surface of NCO-20 nanoplates enhance the OER activity. The superparamagnetic NCO-20 shows enhancement in OER with the external magnetic field due to electron spin polarization. Thus, the present study is of high technological potential in OER performance and possible commercialization due to scalable production.