Difunctional hierarchical CoxP QDs-MoS2@Ni3S2/NF nanostructure as advanced electrocatalyst for water electrolysis

A Co x P QDs-MoS 2 nanosheets@Ni 3 S 2 nanoarrays/NF with electrocatalytic overall water splitting is fabricated via a simple hydrothermal-electrodeposition method. There, the MoS 2 @Ni 3 S 2 /NF is prepared by a hydrothermal method on the surface of NF, and subsequently the Co x P QDs are deposited by an electrodeposition method on the surface of MoS 2 nanosheets. As demonstrated, the as-prepared Co x P QDs-MoS 2 @Ni 3 S 2 /NF presents low overpotentials of 54 mV(HER) at 10 mA cm −2 and 207 mV(OER) at 100 mA cm −2 in 1.0 M KOH, and exhibits a decent overall water splitting performance, including the overpotential of 1.39 V(vs RHE) at 10 mA cm −2 , which can be mainly ascribed to the hierarchical nanostructure can increase MoS 2 nanosheets and Co x P QDs efficiently for increasing the HER/OER active sites. Additionally, the extra HER active sites of edge S atoms from MoS 2 nanosheets, the extra OER active sites induce by the presence of Ni 3+ /Ni 2+ and Co 3+ /Co 2+ mixed state, and low overpotential of Ni 3 S 2 , MoS 2 and Co x P QDs are also important reasons.