Exploring the Potential of Self-Supported Laser-Induced Graphene-Cobalt Oxide Electrodes for Alkaline Electrolysis.

Abstract

A simple, fast, and cost-effective strategy to fabricate self-supported electrodes based on laser-induced graphene (LIG) decorated with cobalt oxide (LIG-CoO) for oxygen evolution reaction (OER) in alkaline media is reported. The method involves a dual-ablation process directly on commercial Kapton tape, eliminating the need for binders, metal current collectors, or post-synthesis thermal/chemical treatments. Raman, scanning electron microscopy, X-ray photoelectron spectroscopy (XPS), and X-ray diffraction analyses confirm the formation of a graphitic and porous LIG network decorated with CoO nanostructures. At the optimal cobalt precursor concentration, the electrochemical evaluation reveals superior OER achieved with an overpotential of 388.0 mV at a current density of 10.0 mA cm^-2 and a Tafel slope of 65.8 mV dec^{- 1}. Electrochemical impedance spectroscopy reveals enhanced charge transfer and increased electrochemical surface area with CoO loading. Notably, synchrotron XPS analysis shows compositional gradients and oxidation states across the electrode depth, confirming Co²⁺ stabilization and surface oxygenation. The proposed fabrication route demonstrates significant potential for scalable production of integrated electrocatalytic materials, addressing the increasing demands for green energy solutions.