Rapid, self-sacrificing template synthesis of two dimensional high-entropy oxides toward high-performance oxygen evolution

The design of high-entropy oxides (HEOs) with specific morphologies and tunable compositions is of great significance for the development of efficient electrocatalysts for the oxygen evolution reaction (OER). Herein, a series of two-dimensional HEOs with abundant active sites are prepared by a self-sacrificing template method via rapid Joule heating. Among them, high-entropy oxide (FeCoNiMoRu) 3 O 4 exhibits outstanding OER performance with low overpotential (199 mV@10 mA cm -2 , 266 mV@100 mA cm -2 ), small Tafel slope (40 mV dec -1 ), and excellent long-term stability (operating at 500 mA cm -2 for 100 hours without significant decay). The perfect performance of (FeCoNiMoRu) 3 O 4 can be attributed to the large active surface area generated by the nanosheet structure, shortened ion transport pathway, entropy stabilization mechanism and multi-element synergism. Therefore, the two-dimensional high-entropy oxide prepared by using a carbon sacrificial template is expected to be a promising candidate material for industrial water splitting. The large size high-entropy oxides nanosheets were prepared by the self-sacrificing template method via Joule heating in a short period of time, which show high activity (1281 A g −1 @1.55 V vs. RHE) and stability in alkaline OER.