A study on the optical properties and optoelectronic parameters of Sudan dye doped poly(5-hydroxy-L-tryptophane) and P(TER-CO-TRI) polymers

In this paper, the optical properties and optoelectronic parameters of two newly synthesized polymers forming a donor : acceptor (D : A) binary system are investigated, followed by their subsequent doping with Sudan dye to obtain a ternary system. The donor polymer is P(TER-CO-TRI), while the acceptor is poly(5-hydroxy-L-Tryptophane). A cost-effective solution-processing was carried out to obtain different binary and ternary composites with concentration of 0.5 mg/ml. Optical absorption spectroscopy was used to measure the optical response and optoelectronic parameters, while FTIR and cyclic voltammetry were used to assess the structure and molecular energy levels of the polymers. The results revealed that the non-dispersive refractive index and energy gap of binary D : A was decreased from 1.56 to 1.52 eV and from 2.84 to 2.10 eV, respectively, when it was doped with Sudan dye. It was concluded that with the help of doping process, different values of energy band gap, refractive index, dielectric constant, and optical conductivity are achieved. This tuning achievement of the optoelectronic parameters is crucial in determining the possible applications of these materials in the organic electronics, photodiodes and photovoltaic devices.