Large area, flexible ordered mesoporous carbon films from soft templating on polymer substrates

Abstract

Mesoporous carbon films are generally fabricated on rigid substrates that act to provide mechanical stability. Here, instead of utilizing rigid substrates, a thin sheet of polyimide (Kapton) is utilized as the substrate to enable continuous production of sheets of soft templated mesoporous carbon films. The mesoporous carbon film is well adhered to the carbonized Kapton. Although mesoporous carbon is generally considered brittle, carbonization of the coated polyimide yields a tough flexible sheet that can be gently bent or even cut to the desired shape. Characterization with transmission electron microscopy, small angle X-ray scattering and N₂ sorption (B.E.T.) confirms the presence of ordered mesopores that conform to expected structures based upon analogous powders. A simple demonstration of the flexible mesoporous carbons as electrodes for aqueous supercapacitors illustrates that the carbonized Kapton can act as the current collector without significant degradation in performance based on the estimated mass of the active mesoporous carbon film at low rates. The fabrication of ordered mesoporous carbon on Kapton provides a facile route to large area, robust high surface area, conductive materials that could be used for a wide variety of electrochemical applications, especially as sensors.