Fig. 4

Mechanical and electrical characterizations of pure PEDOT:PSS hydrogels. a Nominal stress vs. strain curves of free-standing pure PEDOT:PSS hydrogels in PBS with varying DMSO concentrations. b Young’s moduli and ultimate tensile strains vs. DMSO concentration for pure PEDOT:PSS hydrogels in PBS. c Electrical conductivity of pure PEDOT:PSS hydrogels both in deionized water and in PBS with varying DMSO concentrations. d Electrical conductivity of pure PEDOT:PSS hydrogels at different strain both in deionized water and in PBS. e CV curves for the pure PEDOT:PSS hydrogel on Pt electrode in PBS. Red curve represents the CV curve of bare Pt electrode as a control. f Cyclic electrochemical current pulse injection curves of the pure PEDOT:PSS hydrogel on Pt electrode under between −1.5 V and 1.5 V vs. Ag/AgCl. Values in b–d represent mean and the error bars represent the SD of the measured values (n = 4)