Nickel-foam supported cobalt fluoride hydroxide crystallites as an efficient and durable electrocatalyst for oxygen evolution reaction

摘要

This paper reports the facile hydrothermal synthesis of Co(OH)F crystallites on a nickel-foam (NF) substrate for the oxygen evolution reaction (OER). Scanning and transmission electron microscopy showed that the assynthesized Co(OH)F crystallites consisted of different rhombohedral, octahedral, and decahedral shapes, 0.3-0.5 mu m in size. The desired Co(OH)F catalyst synthesized in this study delivered a lower overpotential of 273 mV at a current density of 10 mA cm-2, with a smaller Tafel slope of only 45 mV dec- 1, compared to other fluoride-containing catalysts because of their unique structural features, higher double-layer capacitance, and rapid charge transfer. Furthermore, a stable potential was maintained for more than 20 h during the chronopotentiometry test at a constant current density of 10 mA cm-2.