PdAu and PdAuAg composite membranes with reduced film thickness using YSZ as a stainless-steel support modifier

Abstract

PdAu and PdAuAg alloy membranes were synthesized on top of YSZ-modified planar porous stainless steel supports by electroless deposition. A uniform, continuous and smooth coverage was observed after three YSZ deposition calcination cycles, with neither uncovered zones nor detachment after calcination at 673 K. Through this modification procedure, we could obtain thinner and more robust PdAu and PdAuAg alloy membranes. These membranes showed higher hydrogen permeance during the evaluations (623–723 K) and high thermal stability during the long-term stability test. The PdAu and PdAuAg membranes exhibited a good performance during the exposure to CO/H2O steam mixture. Contrary to the PdAu membrane, where no significant change on the atomic surface composition was observed, silver segregation was evidenced on the PdAuAg membrane after exposure to CO/H2O steam mixture.