Efficient overall water splitting electrode regulated by Pt nanodots modified NiCo-carbonate hydroxide nanowires on porous rGO matrix

We report a novel strategy for constructing the OWS electrode by modifying nickel-cobalt carbonate hydroxide nanowires (NiCo-CHs) arrays with platinum (Pt) nanodots on a three-dimensional porous reduced graphene oxide (3D-rGO) matrix. The incorporation of Pt nanodots induces substantial modulation in the electronic states of NiCo-CHs, leading to a synergistic heterostructure that favors the OWS. The introduction of 3D-rGO enhances electrical conductivity, facilitates charge transfer, and provides abundant surface sites for the deposition of active components. Consequently, the electrode with a multi-dimensional heterostructure possesses remarkable bifunctional electrocatalytic activity, achieving low overpotentials of 73 mV for HER at −10 mA cm⁻² and 272 mV for OER at 50 mA cm⁻². Furthermore, the electrode exhibits superior reaction kinetics, enhanced charge transfer characteristics, and excellent stability and durability for both HER and OER. When configured into an OWS cell, the device achieves a low operating voltage of 1.40 V at 10 mA cm⁻².