Si-Zr-C-N-based hydrophobic plasma polymer membranes for small gas molecule separation

Abstract

Si-Zr-C-N membranes were studied for an application of hydrogen separation at high temperature. The synthesis of single-source molecular precursor incorporating four elements Si, Zr, C and N in the same molecule has been developed leading to a volatile compound that can be deposited in a gaseous way by plasma enhanced chemical vapor deposition. The obtained thin films were characterized by scanning electron microscopy, infrared spectroscopy and ellipsometry. Gas permeation tests were also performed to determine their performance in terms of permeance and selectivity. A helium permeance of about 4.5.10- 8 mol m- 2 s- 1 Pa- 1 and an ideal selectivity α* He/N2 around 60 have been obtained at 150 C with a transmembrane pressure of 105 Pa. © 2012 Elsevier B.V.