In-situ Reconstruction of High-Entropy Heterostructure Catalysts for Stable Oxygen Evolution Electrocatalysis Under Industrial Conditions.

Despite of urgent needs for highly stable and efficient electrochemical water-splitting devices, it remains extremely challenging to acquire highly stable oxygen evolution reaction (OER) electrocatalysts under harsh industrial conditions. Here, w e report a successful in-situ synthesis of FeCoNiMnCr high-entropy alloy (HEA) and high-entropy oxide (HEO) heterocatalysts via a Cr-induced spontaneous reconstruction strategy, and demonstrate that they deliver excellent ultra-stable OER electrocatalytic performance with a low overpotential of 320 mV at 500 mA cm -2 and a negligible activity loss after maintaining at 100 mA cm -2 for 240 h. Remarkably, the heterocatalyst holds outstanding long-term stability under harsh industrial condition of 6 M KOH and 85°C at a current density of as high as 500 mA cm -2 over 500 h. Density functional theory calculations reveal that the formation of the HEA-HEO heterostructure can provide electroactive sites possessing robust valence states to guarantee long-term stable OER process, leading to the enhancement of electroactivity. The findings of such highly stable OER heterocatalysts under industrial conditions offer a new perspective for designing and constructing efficient high-entropy electrocatalysts for practical industrial water splitting. This article is protected by copyright. All rights reserved.