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

Junyuan Xu (1) , Juliana P. S. Sousa (1) , Natalia E. Mordvinova (2) , Jose Diogo Costa (1) , Dmitri Y. Petrovykh (1) , Kirill Kovnir (3) , Oleg I. Lebedev (2) , Yury V. Kolen'Ko (1)

1 INL - International Iberian Nanotechnology Laboratory
2 CRISMAT - Laboratoire de cristallographie et sciences des matériaux
3 ISU - Iowa State University

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.

Mots clés: OER; Sacrificial Al; Nickel phosphide; In situ catalyst formation; PGM-free catalyst; Electrodes; Inorganic compounds; Electrocatalysts; Radiology; Foams

Domaines: Matériaux

Junyuan Xu, Juliana P. S. Sousa, Natalia E. Mordvinova, Jose Diogo Costa, Dmitri Y. Petrovykh, et al.. Al-Induced In Situ Formation of Highly Active Nanostructured Water-Oxidation Electrocatalyst Based on Ni-Phosphide. ACS Catalysis, 2018, 8 (3), pp.2595-2600. ⟨10.1021/acscatal.7b03817⟩. ⟨hal-02174404⟩