Template-free synthesis of coral-like nitrogen-doped carbon dots/Ni 3 S 2 /Ni foam composites as highly efficient electrodes for water splitting

Abstract Non-noble, high-efficient electrodes with excellent durability are desirable for water splitting. Herein, a facile strategy has been proposed to in-situ grow nitrogen-doped carbon dots (NCDs) decorated Ni 3 S 2 on Ni foam (NCDs/Ni 3 S 2 /NF) by hydrothermal treatment of Ni foam in water solution of thiourea and NCDs. Interestingly, coral-like NCDs/Ni 3 S 2 /NF composites are unprecedentedly prepared without any templates, where the Ni 3 S 2 nanorods mainly expose {021} high-index facets. The resultant NCDs/Ni 3 S 2 /NF composites are directly used as self-supported electrodes for overall water splitting which deliver a current density of 10 mA cm −2 at 1.50 V with excellent durability in 1.0 M KOH solution.