Engineering high-entropy alloy nanosheets toward efficient electrocatalytic water oxidation

Fabricating advanced materials with a high-entropy concept imparts a result in efficient energy conversion and storages, as the configurations of high entropy alloys (HEAs) are optimized through incorporating different atomic species. Herein, we synthesize FeCoNiCrMn HEAs with nanosheet structure through a facile salt-templated approach. Extensive characterizations reveal that the introduction of sodium chloride is beneficial to the formation of high-entropy and nanosheet structures, and the chemical compositions can be modified via the designed annealing temperature. As an example application, the FeCoNiCrMn HEA nanosheets that annealed at 750 ℃ exhibit outstanding electrocatalytic performances for water oxidation, which possess the ultralow overpotential of 294 and 434 mV at the current density of 10 and 300 mA cm−2, respectively, accompanied with long-term electrochemical durability with a negligible decay in alkaline at the current density of 100 mA cm-2 for 100 h. Our work not only offers insights into high-entropy syntheses, but also provides robust electrocatalysts for water splitting.