Magnetic-field guided synthesis of highly active Ni–S–CoFe2O4 electrocatalysts for oxygen evolution reaction. (March 2021)

• Record Type: Journal Article
• Authors: Li, Zihan; Lv, Zunhang; Liu, Xin; Wang, Guixue; Lin, Yusheng; Xie, Guangwen; Jiang, Luhua
• Is Part Of: Renewable energy. Volume 165:Part 1(2021)
• Page Start: 612
• Page End: 618
• Publication Date: 2021-03
• Subjects: Magnetic nanosheets -- Electrocatalysts -- Amorphous Ni–S -- Cobalt ferrite -- Oxygen evolution reaction; Renewable energy sources -- Periodicals; Power resources -- Periodicals; Énergies renouvelables -- Périodiques; Ressources énergétiques -- Périodiques; 333.794
• DOI: 10.1016/j.renene.2020.11.083
• Languages: English
• ISSNs: 0960-1481

Abstract

Abstract: The sluggish kinetics of the four-electron-proton coupled oxygen evolution reaction (OER) limits the efficiency of water splitting. Herein, Ni–S–CoFe2 O4 magnetic nanosheets supported on Ni Foam (Magn-Ni-S-CoFe2 O4 /NF) as highly active OER electrocatalysts are synthesized via an extremely simple magnetic-field guided co-electrodeposition strategy. With the application of magnetic fields, the flower-like structures consisting of numerous nanosheets are obtained. This special interconnected structure can effectively reduce the transfer resistance to electrons during catalysis. The ultra-thin amorphous Ni–S layer at the edge of well-defined crystalline CoFe2 O4 provides more active sites for the reaction because of the abundant defects, which greatly enhances the OER performance. At the same time, the application of magnetic fields changes the chemical state of the electrocatalyst. The well-designed Magn-Ni-S-CoFe2 O4 /NF exhibits excellent OER activity with a low overpotential of 228 mV at the current density of 10 mA cm −2, which is lower than the value of 253 mV for the Ni–S–CoFe2 O4 /NF without applied magnetic field, a small Tafel slope of 72 mV dec −1 and excellent stability for at least 24 h. This work provides a simple magnetic field-assisted synthesis method to prepare electrocatalysts with excellent OER activity. Highlights: A new highly active and cost-effective electrocatalyst: Magn-Ni-S-CoFe2 O4 /NF. An innovative synthesis method: electrodeposition assisted by magnetic field. A excellent electrocatalytic activity of OER: 228 mV/10 mA cm −2 in 1 M KOH.