Nitrogen‐Doped Carbon Dots Modified Fe–Co Sulfide Nanosheets as High‐Efficiency Electrocatalysts toward Oxygen Evolution Reaction

Developing high-efficiency and stable oxygen evolution reaction (OER) electrocatalysts is an imperative requirement to produce green and clean hydrogen energy. In this work, the FeCoS_y /NCDs composite with nitrogen-doped carbon dots (NCDs) modified Fe-Co sulfide (FeCoS_y ) nanosheets is prepared by using a facile and mild one-pot solvothermal method. Benefiting from the low crystallinity and the synergistic effect between FeCoS_y and NCDs, the optimal FeCoS_y /NCDs-3 composite exhibits an overpotential of only 284 mV at 10 mA cm^-2 , a small Tafel value of 52.1 mV dec^-1 , and excellent electrochemical durability in alkaline solution. Remarkably, unlike ordinary metal sulfide electrocatalysts, the morphology, components, and structure of the FeCoS_y /NCDs composite can be well retained after OER test. The NCDs modified FeCoS_y composite with excellent electrocatalytic performance provides an effective approach to boost metal sulfide electrocatalysts for practical application.