High conductivity PEDOT resulting from glycol/oxidant complex and glycol/polymer intercalation during vacuum vapour phase polymerisation

Vacuum vapour phase polymerisation (V-VPP) was used to synthesis high conductivity poly(3,4-ethylenedioxythiophene) (PEDOT) on glycol/oxidant coated substrates. Thermo gravimetric analysis (TGA) indicated that up to 15 wt.-% glycol was able to complex with the Fe(Tos)3 oxidant solution and that this loading produced PEDOT with the highest conductivity, namely 1487 S cm−1. Further addition beyond 15 wt.-% resulted in an unbounded excess of glycol which appeared to inhibit the polymerisation process, resulting in reduced doping levels and conductivity. XPS data showed that glycol was incorporated within the PEDOT matrix after polymer synthesis, and that this may contribute to the high conductivity achieved using the V-VPP technique. XPS data also confirmed that the highest conductivity coincided with the highest recorded doping level, d = 28.4%.