Magnetron sputtered Ir thin film on TiC-based support sublayer as low-loading anode catalyst for proton exchange membrane water electrolysis
Abstract
Proton exchange membrane (PEM) water electrolysis (PEMWE) is getting more attention in recent years as a promising alternative in context of energy storage from renewables. However high prices of platinum and iridium, currently considered to be the state-of-the-art electrocatalysts, prevent wider commercialization of this technology.
In this paper, we present unconventional and cost-effective preparation method of anode catalyst, containing low amount of noble metal. Thin Ir film is magnetron sputtered on TiC-based support sublayer, hot-pressed on anode side of Nafione (R) N115 PEM.
Following three parameters were systematically varied and their impact on PEMWE in-cell performance was evaluated: total TiC-based support material loading on the PEM, ionomer content within the support sublayer and Ir catalyst loading on top of the support sublayer. In addition, TiC-based sublayer underwent accelerated aging procedure, followed by photoelectron spectral analysis to prove its ability to withstand high anodic potentials.
Remarkable PEMWE in-cell performances were obtained, considering amount of used Ir; 1.74 V (with similar to 80 mu g cm(-2) of Ir), 1.72 V (with similar to 160 mu g cm(-2) of Ir) and 1.71 V (with similar to 240 mu g cm(-2) of Ir) at 1 A cm(-2) and 80 degrees C.