Interface engineering and heterometal doping Co-Mo/FeS for oxygen evolution reaction

The sluggish kinetics of the oxygen evolution reaction (OER) limits the development of water electrolysis technology and the long-term efficiency of hydrogen energy production. In addition, it is important to evaluate the reconstruction performance of OER catalysts for actual water electrolysis. We created a self-supported electrode with FeS film coated Fe foam as a substrate, ordered resoluble molybdate (MoO42-) anions in interlayers, and Codoped as a catalytically active phase for the OER. The catalyst is capable of electrochemical self-reconstruction (ECSR). With the dissolution of molybdate and sulfur ions, the catalyst surface cobalt iron oxide (CoFe2O4) forms an active amorphous FeCoOOH, which is favorable for alkaline OER. We realized the introduction of new active sites in the catalyst reconstruction process. Finally, the composite CoFeOx catalyst increased the specific surface area, promoted bubble transport, and enhanced electron mass transfer. The synergistic coupling effect of the catalyst makes it have excellent OER activity and stability. Remarkably, Co-Mo/FeS nanosheets afforded an electrocatalytic OER with a current density of 100 mA cm-2 at a low overpotential of 321 mV. These discoveries open up new opportunities for the application of doping and template-directed surface reconfiguration, which holds promise as an effective electrocatalyst for the OER. & COPY; 2023 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

The slow kinetics of the oxygen evolution reaction (OER) hinders the progress of water electrolysis technology and the long-term efficiency of hydrogen energy production. By creating a self-supported electrode with FeS film coated Fe foam as a substrate, ordering resoluble molybdate (MoO42-) anions in interlayers, and codoping as a catalytically active phase, an electrochemically self-reconstructing (ECSR) catalyst for OER is developed. The catalyst introduces new active sites through the dissolution of molybdate and sulfur ions, resulting in improved OER activity and stability.