Synthesis, characterization, electrical and luminescence performance of novel copolymer of anthracene/pyrrole

Abstract

A novel copolymer of anthracene/pyrrole at their different mole ratios has been prepared by facile oxidative coupling of anthracene and pyrrole using FeCl3 as a catalyst in nitrobenzene/n-hexane. The prepared copolymers were analyzed by using FTIR, 1HNMR, XRD, GPC and thermogravimetric techniques. The SEM photographs of copolymers exhibit uniform morphology and their crystallites arranged with random orientations. The temperature dependent electrical conductivity of copolymers was changed with respect to pyrrole concentration. The observed red shift in UV–Visible and excitation spectra of copolymers with pyrrole contents indicates the formation of large conjugation in their main chain. The fluorescence spectra of solid powder of copolymers was observed in the green region at maximum wavelength 518 nm with the addition of anthracene contents. However, the copolymer in the solution of concentrated sulphuric acid exhibited tuning of emission towards the red side. Furthermore, the copolymer excited at the maximum absorption wavelength (340 nm) of the pyrrole shows same emission band, indicating efficient energy transfer between pyrrole and anthracene units. Therefore, the present study shows improved thermal, electrical and optical properties of copolymers, which have practical applications in the fields of optoelectronic devices such as organic light emitting diode, conducting devices, solar cells etc.