Free-Standing Ni nanoparticles wrapped in electrochemically reduced graphene Oxide: A highly efficient electrocatalyst for hydrogen evolution in acidic conditions

Abstract

This study presents an eco-friendly, one-pot electrochemical method for fabricating flexible, free-standing electrodes composed of nickel nanoparticles (NiNPs) wrapped in electrochemically reduced graphene oxide (ERGO). The process involves simultaneous reduction of GO and Ni²⁺ ions on indium-doped tin oxide (ITO) substrates, followed by detachment using H₂ bubbling delamination. Characterization revealed uniform distribution of NiNPs within ERGO layers, providing abundant active sites. After electrochemical activation, the NiNPs/ERGO electrodes demonstrated exceptional hydrogen evolution reaction (HER) performance in 0.5 M H₂SO₄, with a low overpotential of 73 mV at 10 mA cm⁻², a Tafel slope of 31 mV dec⁻¹, and outstanding durability. This innovative approach offers potential for developing high-performance electrocatalysts for water splitting and other applications.