Sacrificial Layer and Supporting Layer Techniques for the Fabrication of Ultra-Thin Free-Standing PEDOT:PSS Nanosheets

Abstract

ABSTRACTAim of this work was to realize free-standing conductive nanofilms having very large surface area with typical nano-scale thickness (40-120 nm) by modifying existing approaches for nanostructured thin films assembly. We tested and optimized two different fabrication methods for the obtainment of free-standing conductive ultra-thin nanosheets based on the conductive polymer poly(3,4-ethylenedioxythiophene)/poly(styrene sulfonate) (PEDOT:PSS). Supporting Layer and Sacrificial Layer techniques permitted the obtainment of single layer nanofilms that can be released in water and of LbL multilayer nanosheets (PEDOT:PSS/Polyelectrolytes) that can be released in acetone, respectively. Here we describe the details of both the proposed fabrication methods and compare the properties of the realized nanosheets in terms of thickness, contact angle and conductivity. Interestingly, the realized free-standing nanosheets, despite their low thickness, are very robust and compliant while maintaining their structure and functionality. Possible applications are foreseen in the field of sensing and actuation, as well as in the biomedical field, e.g. as smart conductive substrates for cell culturing and stimulation.