One-step synthesis of mesoporous Cobalt sulfides (CoSx) on the metal substrate as an efficient bifunctional electrode for overall water splitting

Electrocatalysts based on transition metal sulfides (TMSs) are drawing accelerating concerns in renewable energy research because of their intrinsically excellent activities towards both hydrogen evolution reaction (HER) and oxygen (OER). To date, considerable efforts made to improve the performance these catalysts, but ignoring improper synthesis strategy would incur additional cost catalyst. Herein, a convenient, one-step anodization method is developed for fast construction cobalt (CoSx). Without any high-temperature or long-time treatment, mesoporous CoSx self-grown substrate minutes. As result, as-anodic requires overpotentials 102 mV HER 284 OER achieve current density 10 mA m−2 alkaline solution. Moreover, tandem bifunctional exhibits required cell voltage 1.64 V overall water splitting solution, exceeding most documented Co-based electrocatalysts.