Bismuth activated succulent-like binary metal sulfide heterostructure as a binder-free electrocatalyst for enhanced oxygen evolution reaction.

Oxygen evolution reaction (OER) is the key to achieve highly efficient hydrogen production during water splitting. Herein, flexible nanorods-integrated succulent-like Bi2S3/Ni3S2/NF heterostructure has been prepared by a facile solvothermal method and applied for OER. We highlight the unique nonequivalent sp3 hybridization of P-region metal based sulfides, which makes a possibility of electronic inductive effect and enhanced electrocatalytic performance. The Bi2S3/Ni3S2/NF catalyst shows low overpotential 268 mV at 10 mA cm−2 and low Tafel slope of 82 mV dec−1. Long-term stability evaluated at high current density suggests that succulent-like Bi2S3/Ni3S2 could be a promising alternative to noble-metal based electrocatalysts for water oxidation reaction in alkaline medium.