Electrodeposition and electrochromic properties of N-ethyl substituted poly(3,4-ethylenedioxypyrrole)

N-Ethyl substituted poly(3,4-ethylenedioxypyrrole), a new electrochromic polymer, has been produced and its spectroelectrochemical properties have been investigated. This material displays multicolor electrochromism, switching between green, violet, and grey. Three different electrochromic devices have been laminated and evaluated using the electrochromic polymer, an ion-conducting polymer electrolyte, and one of the following counterelectrodes: tungsten oxide, polyaniline, or poly-di-methyl-(3,4-propylenedioxythiophene).     

非晶Cu_xO-WO_3和V_2O_5-WO_3膜电色机理研究

本文对两个双氧化物非晶膜(Cu_xO-WO_3、V_2O_6-WO_3)光学特性及电致变色机理进行了研究。结果表明,此类薄膜的颜色和透过率能够连续、可逆变化。这种多色化效应是由于Cu_xO-WO_3膜中发生Cu~(2 )(?)Cu~ 与W~(6 )(?)W~(5 )顺序转变和V_2O_5-WO_3膜中发生V~(5 )(?)V~(4 )可逆转变而造成的。因此,它们有可能用于选择性透过窗或信息显示器件。     

A study on the electrochromic properties of polyaniline/silica composite films with an enhanced optical contrast

A polyaniline (PANI)/silica (SiO₂) composite film was prepared by a simple in situ electrodeposition method, and its electrochromic (EC) properties were studied. When PANI was electrodeposited in the presence of SiO₂ particles, the resulting PANI/SiO₂ composite films possessed higher surface areas, larger redox charge capacities, and higher doping levels, thus enhanced optical contrasts. By incorporating SiO₂ particles into the PANI film, the transmittance change at 700 nm from 10.7% to 16.4%, or an enhancement of ca. 50%, was achieved when operating between −0.5 V and 0 V. In addition, x-ray photoelectron spectroscopy (XPS) indicated that the formation of the highly oxidized PANI might have been retarded through the addition of SiO₂ particles. Furthermore, the growth mechanism of the PANI/SiO₂ composite film was proposed.     

Electrochromism of Crystal Violet Lactone in the presence of Fe(III)/Fe(II) redox pair

Selective interaction between Crystal Violet Lactone and Fe³⁺/Fe²⁺ in methanol leads to a reversible ionochromic colour change. This interaction can be controlled electrochemically, in order to achieve reversible colour changes with high contrast between colourless and dark blue solutions. The presented system is proposed as an alternative electrochromic solution.