Optimized protocol for the preparation of multi-walled carbon nanotube:polystyrene transducers for electrochemical sensing

Abstract

A practical method is presented to prepare films of a composite material constituted of multi-walled carbon nanotubes (MWCNTs) and polystyrene (PS) that are used for transduction applications. The method, which can be carried out by employing usual lab equipment, is simple, low-cost, rapid, and nonpolluting. Furthermore, it is compatible with microelectronic fabrication technology and is scalable for mass production. For designing this method, we studied how the number of drop-casted composite layers, the temperature used for curing the samples, and the duration of this thermal treatment influence on the electrochemical performance of a Si/SiO2/Au/MWCNT:PS electrode. The optimum electrochemical responses of the Si/SiO2/Au/MWCNT:PS electrode were obtained with films prepared with four layers of MWCNT:PS composite, each cured at 80 °C for 15 min. Under these conditions, the MWCNT walls are exposed and readily accessible for subsequent functionalization.