Graphene/poly(3,4-ethylenedioxythiophene) hydrogel with excellent mechanical performance and high conductivity

We report a novel and easy route to synthesize a mechanically strong hydrogel composed of graphene and poly (3,4-ethylenedioxythiophene) (PEDOT). 3,4-Ethylenedioxythiophene played the role of reducing agent to convert a highly oxidative graphite oxide (h-GO) to graphene and in situ polymerized itself synchronously on the active sites of the graphene to construct the hydrogel. The content of the carbonyl groups in h-GO was found to have a major impact on the generation of the hydrogel. Also the morphology and the quantity of PEDOT formed in the hydrogel were considered to be the key factors for improving the mechanical performance of the hydrogel. As-prepared enhanced graphene/PEDOT hydrogel displayed a compressive fracture stress as high as 29.6 MPa, a storage modulus about 2.1 MPa at 10 rad/s, a good electrical conductivity of 0.73 S/cm and a high specific capacitance of 174.4 F/g, which make it a potential candidate for a number of technologies such as electrochemical sensor and supercapacitor.