Fabrication of thin-film electrochemical sensors from single-walled carbon nanotubes by vacuum filtration Original Research Article

We report a simple strategy for fabricating a thin-film filtering membrane electrode (FME) of single-walled carbon nanotubes (SWCNTs) by vacuum filtration. A SWCNT–FME, comprised of SWCNTs and mixed cellulose ester (MCE), is applicable in two detection modes. The face-mode SWCNT–FME directly employs the exposed SWCNT sensing layer and possesses remarkable properties as thin-film electrochemical sensor platforms, including good flexibility, wide potential window, large surface area and excellent analytical performance resembling traditional carbon nanotube-based electrochemical sensors. The back-mode SWCNT–FME has a tunable selectivity produced by combining the separation function of the outer MCE membrane with the high surface area of the inner SWCNT sensing layer. As an example of surface functionalization, an electrodeposition method was proposed for the controlled decoration of a SWCNT–FME with either low-density discrete flower-like gold nanoparticles (GNPs) or continuous GNP films. The resulting SWCNT–GNP composites were proved to possess high surface area and excellent electrocatalytic activity for the oxidation of glucose.