An investigation on the performance of Di-isopropyl benzyl derivative of Poly (3, 4-propylene dioxythiophene) thin film based electrochromic pixels displays

Abstract

Electrochromic (EC) smart pixel display was designed and fabricated using a novel monomer di-4-isopropyl benzyl substituted (3, 4-propylene dioxythiophene) (ProDOT-IPBz2). The polymer thin film showed absorption between 450 and 650 nm at a fully reduced state. The absorption peak narrowed down slightly towards longer wavelength region (850–900 nm) at the oxidation states. Siju et al has reported the coloration efficiency (CE) of the thin film as ∼305 cm2C−1. The ProDot-IPBZ2 thin film was used to fabricate EC pixel display of 2 × 2 pixel array on a patterned ITO coated glass. The optical color contrast of the EC pixel display is 40% at 600 nm, with a switching time of about 2 s and 2.5 s respectively. The CE of EC pixel was found to be 555 cm2C−1 at 600 nm in the fully doped state. This EC pixel switched for more than 1000 cycles with good color contrast (<5% T). EC pixel displays showed transmissive, magenta and violet colored states at applied potentials of 1.5, −1.0 and −2.0 V respectively. This EC pixel display is efficient with faster response time and better color contrast.