Creating Hyperthin Membranes for Gas Separations

Interest in creating membranes that can separate gases has intensified in recent years owing, in large part, to climate change. Specifically, the need for separating CO2 and N-2 from flue gas in an economically viable fashion is now considered urgent. This Perspective highlights two recent developments from my laboratory-defect repair of polyelectrolyte multilayers (PEMs) using micellar solutions of sodium dodecyl sulfate (SDS) and the surface modification of a highly permeable polymer, poly[1-(trimethylsilyl) propyne] (PTMSP)-which I believe have significant implications not only for this CO2/N-2 problem but also for the ever-growing area of layer-by-layer (LbL) thin films. A brief mention is also made of past efforts that have been aimed at creating hyperthin membranes from porous surfactants and from PEMs with a view toward gas separations.