Conductivity and optical studies of plasticized solid polymer electrolytes doped with carbon nanotube

► Optical band gap values show the decreasing trend with an increasing dopant concentration. ► It is also observed that the absorption edge shifted to longer wavelength on doping. ► Results of the optical measurements indicate the presence of a well-defined π→π⁎ transition associated with the formation of a conjugated C=O and/or C=O electronic structure.