Elaboration and characterization of ruthenium nano-oxides for the oxygen evolution reaction in a Proton Exchange Membrane Water Electrolyzer supplied by a solar profile

Highly crystalline rutile-like structure ruthenium oxide material was synthesized from the hydrolysis method. A heat-treatment procedure was effective to recover catalyst powders free from organic carbon species which could be resulted in the traces of ethanol as solvent. Voltammetry (CV and LSV) and electrochemical impedance Spectroscopy (EIS) were used to determine the capacitance and the kinetic parameters of the RuO2 anodes for the oxygen evolution reaction (OER). The utilization of this catalyst as anode in a single cell PEM electrolyzer has shown high activity toward pure H-2 and O-2 gases production. Exchange current density and Tafel slope of 3.3 10(-8) A cm(-2) and 51 mV dec(-1), respectively determined at 60 degrees C, showed that the H2O oxidation to O-2 was limited by intermediate species formation step. During the durability tests in a 25 cm(2) single PEM water electrolyzer (PEMWE) supplied by a solar power profile, the area resistance was raised in the 300-345 m Omega cm(2) range and an efficiency loss of 330 mu V h(-1) was measured from 1.85V at 1 A cm(-2) and 80 degrees C. (C) 2014 Elsevier Ltd. All rights reserved.