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)3O4 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)3O4 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.