One-step chemical transformation synthesis of CoS2 nanosheets on carbon cloth as a 3D flexible electrode for water oxidation

Water electrolysis is an important way to gain pure hydrogen, while it is restricted by the sluggish kinetics of oxygen evolution reaction . To improve hydrogen production capability, it is critical to search for low-cost, earth-abundant, and superior catalytic activity materials as electrocatalysts for water oxidation . Herein, one-step chemical transformation strategy is utilized to synthesize cobalt sulfide nanosheets supported on the carbon cloth through the sulfuration process of the Co 3 O 4 precursor. The catalyst exposes abundant active sites and facilitates charge transfer, which is beneficial to water oxidation. In alkaline electrolyte , the catalyst as a non-noble metal electrode exhibits sparkly performance for water oxidation. To achieve current densities of 10 and 100 mA cm −2 , the overpotentials as low as 291 and 364 mV are demanded, respectively. Moreover, cobalt sulfide nanosheets on the carbon cloth manifest a small Tafel slope of 69 mV dec −1 and robust long-term durability. In addition, this one-step chemical transformation strategy can be utilized to synthesize cobalt selenide nanosheets on the carbon cloth, providing an orientation for developing other binder-free electrocatalysts for water oxidation.