Controlling the optical properties of polyaniline doped by boric acid particles by changing their doping agent and initiator concentration

Abstract

In this study, polyaniline doped by boric acid (PAni:BA) conducting polymers were chemically synthesized by oxidative polymerization method using (NH 4 ) 2 S 2 0 8 (APS) as initiator. Pani:BA conducting polymers were synthesized by using two different APS/aniline molar ratios as 1:1 and 2:1. Their results were compared with PAni doped by HCl (PAni) conducting polymer. Structural properties of the PAni, PAni:BA (1:1) and PAni:BA (2:1) conducting polymers were characterized by using FTIR, SEM, TGA, particle size and apparent density measurements. Effects of doping agents and initiator concentrations on optical properties were investigated in detail. The optoelectronic parameters such as absorption band edge, molar extinction coefficient, direct allowed band gap, refractive index, optical conductance and electrical conductance of the PAni, PAni:BA (1:1) and PAni:BA (2:1) were determined. The absorption band edge and direct allowed band gap of PAni were decreased with doping BA and increasing APS ratio. Also, the refractive index values of the materials were calculated from experimental results and compared with obtained results from Moss, Ravindra, Herve-Vandamme, Reddy and Kumar-Singh relations. © 2017 Elsevier B.V.