Fabrication of amorphous FeCoNiCuMnP high-entropy phosphide/carbon composites with a heterostructured fusiform morphology for efficient oxygen evolution reaction

Amorphous high-entropy materials with abundant defects, coordinatively unsaturated sites, and loosely bonded atoms could exhibit excellent electrocatalytic performance. However, how to fabricate such materials with nanostructure as well as amorphous structure is still full of challenges. In this work, high-entropy metal organic framework (HE-MOF) is employed as the self-sacrificial template to fabricate FeCoNiCuMnPx high-entropy phosphide/carbon (HEP/C) composites. The obtained composite shows a heterostructured fusiform morphology, in which the HEP is encapsulated by a carbon layer, revealing high electron conductivity as well as rich catalytic active sites for oxygen evolution reaction (OER). Beside, it is found that there is a short-range ordered crystal structure in the amorphous phase, which is beneficial for revealing high OER catalytic activity as well as good stability. As a result, the optimum HEP/C composite shows an overpotential 239 mV@10 mA cm−2 with a small Tafel slope of 72.5 mV dec−1 for catalyzing OER in alkaline solution.