Transition-metal doped cobalt phosphide nanostructures as electrocatalysts for water splitting

Because the global demand for energy rapidly increased in the past decades, scientists are looking for renewable and clean energy with the aim of substituting for fossil fuels. Hydrogen has been considered as a high density energy and clean fuel, so that the electrolysis of water for hydrogen production may be a promising way to solve the energy crisis and environment pollution. However, most of highly active electrocatalysts are commonly precious metal, their major drawbacks are high cost and insufficient reserve that restricts practical application. As a result, developing earth-abundant, active and stable catalysts which can operate in the same electrolyte for water-splitting is important for many renewable energy conversion processes. In this research, we utilized the gas-solid reaction to synthesize the cobalt phosphide with dopant of iron. Because the transition metal phosphides (TMPs) are characteristic of metallic properties, which can facilitate the water-splitting reaction owing to an effective charge-transfer. The morphology and catalytic capability can be further modified via doping various amount of iron. Finally, combination of the iron doping and carbon cloth as a hybrid material with flexible and conductive properties can facilitate the charge transfer from substrate to catalyst and lead to an enhanced performance. Besides, bubble releasing problem during the reaction can be remarkably suppressed owing to 3D structure of carbon cloth. Consequently, we successfully synthesized the hybrid material that can perform excellent activities toward both the oxygen and hydrogen evolution reaction. These strategies of TMPs are instructive for designing non-noble metal catalysts for future applications.