Affiliation: | aDepartment of Physics, Tezpur University, Napaam, Tezpur, Assam-784 028, India bNuclear Science Centre, Aruna Asaf Ali Marg, New Delhi-110 067, India |
Abstract: | Electronically conducting polymers are suitable electrode materials for high performance supercapacitors, for their high specific capacitance and high dc conductivity in the charged state. Supercapacitors and batteries are energy storage and conversion systems which satisfies the requirements of high specific power and energy in a complementary way. Ion beam {energy > 1 MeV} irradiation on the polymer is a novel technique to enhance or alter the properties like conductivity, density, chain length and solubility. Conducting polymer polypyrrole thin films doped with LiClO4 are synthesized electrochemically on ITO coated glass substrate and are irradiated with 160 MeV Ni12+ ions at different fluence 5 × 1010, 5 × 1011 and 3 × 1012 ions cm−2. Dc conductivity measurement of the irradiated films showed 50–60% increase in conductivity which is may be due to increase of carrier concentration in the polymer film as observed in UV–Vis spectroscopy and other effects like cross-linking of polymer chain, bond breaking and creation of defects sites. X-ray diffractogram study shows that the degree of crystallinity of polypyrrole increases in SHI irradiation and is proportionate to ion fluence. The capacitance of the irradiated films is lowered but the capacitance of the supercapacitors with irradiated films showed enhanced stability compared to the devices with unirradiated films while characterized for cycle life up to 10,000 cycles. |