Al-Induced In Situ Formation of Highly Active Nanostructured Water-Oxidation Electrocatalyst Based on Ni-Phosphide

We report a simple low-cost concept for the preparation of water-oxidation electrocatalyst via modification of self-supported Ni5P4-Ni2P foam catalyst precursor with Al. As an anode for alkaline oxygen evolution reaction, this material exhibits an impressive Tafel slope of 27 mV dec(-1) and offers anodic current densities of 10, 100, and 300 mA cm(-2) at overpotentials of merely 180, 247, and 312 mV, respectively. Moreover, the anode demonstrates high operational stability, as reflected by a steady-state performance for more than 8 days. Combining state-of-the-art electron microscopy and photoelectron spectroscopy, we investigated the role of the Al dopant in the formation of active Ni(OH)(2)/NiO/Ni5P4-Ni2P nanocatalyst, which exhibits oxygen-evolving activity among the highest reported to date.