High‐Throughput Screening of Co‐Fe‐Ni Electrocatalysts for High‐Current‐Density Water Electrolysis

Abstract

Developing oxygen evolution (OER) catalysts with opti­mum composition and highly active catalytic centres is a challenge during electrode scale‐up. We show a selection strategy for the optimum composition of Co‐Fe‐Ni catalyst systems through a scanning droplet cell‐based high‐throughput screening on thin‐film materials libraries, followed by fabrication and testing of the selected compositions in form of catalyst‐coated porous electrodes for the OER in alkaline media. The electrode with optimum composition (Co17Ni58Fe25_Ni foam) exhibits a high current density of 1 A cm‐2 during water electrolysis at an operating potential of ~1.9 V.