Novel non-alloy Ru/Pd composite membrane fabricated by electroless plating for hydrogen separation

This study presents a new non-alloy Ru/Pd composite membrane fabricated by electroless plating for hydrogen separation. It shows that palladium and ruthenium can be deposited on an aluminum-oxide-modified porous Hastalloy by using our new EDTA-free plating bath at room temperature and 358 K, respectively. A 6.8 μm thick non-alloy Ru/Pd membrane film could be plated and helium leak test confirmed that the membrane was free of defects. Hydrogen permeation test showed that the membrane had a hydrogen permeation flux of 4.5 × 10−1 mol m−2 s−1 at a temperature of 773 K and a pressure difference of 100 kPa. The hydrogen permeability normalized value with thickness of the membrane was 1.4 times higher than our pure Pd membrane having similar structure. The EDX profiles of the front and back side membrane, cross-sectional EDX line scanning and XRD profile show that there was no alloying progress between the palladium and ruthenium layer after hydrogen permeation test at 773 K.