Anodized bulk FeCoCrNiTi_0.6 high-entropy alloy electrocatalysts for long-term industrial-scale oxygen evolution...

For electrochemical water splitting, oxygen evolution reaction (OER) with a complex four-electron coupled process requiring high overpotential is a key process for hydrogen production. Therefore, the development of highly efficient and low-cost OER electrocatalysts is significant for green hydrogen production. In this work, a thin-walled bulk FeCoCrNiTi_0.6 high entropy alloy (HEA) was fabricated through laser additive manufacturing (LAM) followed by a simple one-step anodization. It is found that the HEA anodized for 15 min can realize ultra-high OER activity with low overpotentials of 234, 333, and 651 mV to reach the current densities of 10, 100, and 500 mA cm^-2. Additionally, the anodized HEA displays excellent stability at 600 mA cm^-2 for over 1000 h. Our study shows that anodized bulk FeCoCrNiTi_0.6 HEA has a promising application in industrial green hydrogen production.