In-situ growth of Ni–CoSe2 on biomass-derived carbon tubes as an efficient electrocatalyst for overall water splitting

The construction of efficient non-noble metal bifunctional electrocatalysts for the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is a major challenge to improve the overall water splitting efficiency. Herein, by further selenization of NiCoO2 on biomass-derived carbon tubes (BCT), Ni–CoSe2/BCT composite is obtained and used as an electrocatalyst for overall water splitting. The abundant catalytically active sites of transition metal selenide combined with the enhanced charge transfer efficiency of BCT endow this composite catalyst high OER (overpotential of 325 mV at 10 mA cm−2) and HER (overpotential of 250 mV at 10 mA cm−2) activities. When Ni–CoSe2/BCT is used for electrochemical overall water splitting, a current density of 10 mA cm−2 can be achieved with a small voltage of 1.69 V, demonstrating its promise for overall water splitting. The current work presents a green, economical, and facile synthesis strategy to obtain efficient bifunctional electrocatalysts for overall water splitting.