Processing and Carbon Nanotube Actions on Functional Behavior of Poly(3,4‐Ethylenedioxythiophene): Poly (Styrene Sulfonate) Conductive Polymer

ABSTRACT This research explored the integration of MWCNTs (multiwalled carbon nanotubes) as reinforcing agents to improve the optoelectrical properties of the Poly(3,4‐ethylenedioxythiophene):Poly(styrene sulfonate) thin film (PEDOT:PSS). This integration provided enhanced mechanical robustness and electrical conductivity, owing to MWCNT's high aspect ratio and superior conductive properties. Composite films incorporating MWCNTs at varying concentrations (0.5, 1, 3, and 5 wt%) were fabricated by spin coating followed by thermal annealing. The resulting devices underwent characterization to determine their electrical conductivity, pressure sensitivity, response time, mechanical flexibility, hysteresis, and structural properties. The incorporation of 3 wt% MWCNTs resulted in optimal performance, demonstrating a significant increase in sensitivity and electrical conductivity without compromising the device's flexibility. This composition's electrical conductivity was increased to 47 S/cm, with a pressure sensitivity of 0.57 kPa −1 and a response time of 80 ms, higher mechanical flexibility (25%), and a lower hysteresis ratio (3.9). The ultrasonication process leads to a more uniform MWCNT conformation as observed by SEM analysis, and edge cuts lead to partial density defects. Thus, the current study suggests a promising approach to modify PEDOT:PSS characteristics via MWCNT incorporation, facilitating the development of advanced, flexible pressure sensors.