Efficient Co-doped Pyrrhotite Fe0.95S1.05 Nanoplates for Electrochemical Water Splitting

Abstract The development of highly performed bi-functional electrocatalysts for both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) with low cost materials has remained a great challenge in electrochemical water splitting. Herein, we design and develop a novel Co-doped Fe0.95S1.05 nanoplates, which was synthesized using Fe(CO)5 as precursor for the first time via one pot reaction. Fe0.9Co0.05S1.05 lead to enhanced OER activity with a low overpotential of ∼ 0.27 V at 20 mA/cm2, small Tafel slope of ∼ 46 mV/decade, as well as improved HER activity with a Tafel slope of 114 mV/decade and a current density of 20 mA/cm2 at an overpotential of ∼ 0.385 V. This study produces the most active pyrrhotite FeS based catalyst towards electrochemical water splitting, which suggests a scalable, low cost, simple, and highly efficient catalyst for water splitting.