Self-supporting hybrid silica membranes with controlled porous architectures

Abstract

Bioinspired by the nanoporous architectures in living organisms, self-supporting membranes that contain nanopores have attracted extensive attention due to their transferrable property and promising applications in the fields of separation, filtration, sensing and catalysis. Due to the simplicity and operability, silica sol–gel processing and templating methods can be combined to fabricate self-supporting nanoporous silica membranes. Aiming at controllable porous architectures and mechanical flexibility of the silica membrane, a simple method to fabricate flexible, transferable, self-supporting hybrid silica membranes with controlled and ordered porous architectures has been developed. At first, self-assembly at the gas/liquid interface was used for the preparation of ordered latex spheres with controlled layers. Using such ordered spheres on a sacrificial ITO support as the template, self-supporting silica membranes containing ordered porous architectures were constructed. Then, multi-walled carbon nanotubes were introduced into such porous silica membranes to increase flexibility. Moreover, gold nanoparticles were deposited onto the pore walls of the self-supporting silica membranes to show the possibility for selective recognition, which shows that such self-supporting hybrid silica membranes with controlled porous architectures can be chemically modified and transferred into other surfaces for promising applications in the fields of separation, catalysis and sensing.