New Methodology to Create Ultra-Thin Membranes

Achievement date: 

Ultra-thin membranes composed of arrays of closely packed pores, surface modified to a depth of 18 nanometers, were developed by researchers at the Center for Innovative and Strategic Transformation of Alkane Resources (CISTAR), an NSF-funded Engineering Research Center (ERC) based at Purdue University.


Because the flow of gases through a membrane depends inversely on the membrane’s thickness, thin membranes can allow more gases to flow in a given time. The methodology developed with CISTAR support allows for subsequent deposition of super-thin layers of alumina, silica, or palladium—which allow the membranes to operate at the high temperatures often required in refining hydrocarbons.


To design the methodology, CISTAR researchers developed a nanotech process that allows for atomic-layer deposition of refractory ceramics—silica, alumina, palladium, and microporous silica. Based on application, the coating materials have a high melting point, good thermal and chemical stability, and thermal expansion coefficient close to the substrate material.

The methodology allows for the synthesis and optimization of ultra-thin, thermally stable mesoporous silica-based membranes for separating hydrogen or other gases.