Effect of regioregularity on specific capacitance of poly(3-hexylthiophene)

In this communication, we investigate the effect regioregularity of poly(3-hexylthiophene) (P3HT) on the specific capacitance. P3HTs with regioregularities 96, 70 and 58% have been synthesized by Grignard metathesis (GRIM) and FeCl3 methods. The regioregularity of P3HTs are characterized by nuclear magnetic resonance (NMR), UV–Vis spectroscopy, differential scanning calorimetry (DSC) and X-ray diffraction (XRD) studies. Electrochemical characterizations of the P3HTs reveal significant increase in the specific capacitance with increase in regioregularity. Electrochemical impedance spectroscopy analysis indicates that the charging process is facilitated by increase in regioregularity in P3HT. Stability of P3HTs during repeated charge–discharge cycles, also found to increase with increase in regioregularity.

► Effect of regioregularity on the specific capacitance of P3HT.
► Higher the regioregularity higher the specific capacitance.
► Resistance during electrochemical doping decreases with increase in regioregularity.
► Cycling stability increases with increase in regioregularity.