Electrochromism

About: Electrochromism is a research topic. Over the lifetime, 13097 publications have been published within this topic receiving 294637 citations.

Transparent conductive electrodes for electrochromic devices: A review

Abstract: This paper reviews the optical and electrical performance of thin films that are useful as transparent electrodes in electrochromic devices. The properties of certain heavily doped wide-bandgap semiconductor oxides (especially In2O3:Sn) and of certain coinage metal films are discussed.

Enhanced Contrast Ratios and Rapid Switching in Electrochromics Based on Poly(3,4-propylenedioxythiophene) Derivatives

Abstract: Dark opaque blue to transmissive light blue is the color transition that poly(3,4-propylenedioxythiophene) (PProDOT) and derivatives undergo when switched from their reduced to oxidized state. These polymers are very promising electrochromic materials - they exhibit more rapid switching, lower oxidation potentials, and greater stability than polythiophene. The synthesis and optical properties of the disubstituted derivative PProDOT-Me2 are reported and compared with those of PProDOT-Me and PProDOT. Substitution is found to improve the polymers electrochromic properties.

Synthesis of oxidation-resistant cupronickel nanowires for transparent conducting nanowire networks.

Abstract: Nanowires of copper can be coated from liquids to create flexible, transparent conducting films that can potentially replace the dominant transparent conductor, indium tin oxide, in displays, solar cells, organic light-emitting diodes, and electrochromic windows. One issue with these nanowire films is that copper is prone to oxidation. It was hypothesized that the resistance to oxidation could be improved by coating copper nanowires with nickel. This work demonstrates a method for synthesizing copper nanowires with nickel shells as well as the properties of cupronickel nanowires in transparent conducting films. Time- and temperature-dependent sheet resistance measurements indicate that the sheet resistance of copper and silver nanowire films will double after 3 and 36 months at room temperature, respectively. In contrast, the sheet resistance of cupronickel nanowires containing 20 mol % nickel will double in about 400 years. Coating copper nanowires to a ratio of 2:1 Cu:Ni gave them a neutral gray color, making them more suitable for use in displays and electrochromic windows. These properties, and the fact that copper and nickel are 1000 times more abundant than indium or silver, make cupronickel nanowires a promising alternative for the sustainable, efficient production of transparent conductors.

A bi-functional device for self-powered electrochromic window and self-rechargeable transparent battery applications

Abstract: Electrochromic smart windows are regarded as a good choice for green buildings. However, conventional devices need external biases to operate, which causes additional energy consumption. Here we report a self-powered electrochromic window, which can be used as a self-rechargeable battery. We use aluminium to reduce Prussian blue (PB, blue in colour) to Prussian white (PW, colourless) in potassium chloride electrolyte, realizing a device capable of self-bleaching. Interestingly, the device can be self-recovered (gaining blue appearance again) by simply disconnecting the aluminium and PB electrodes, which is due to the spontaneous oxidation of PW to PB by the dissolved oxygen in aqueous solution. The self-operated bleaching and colouration suggest another important function of the device: a self-rechargeable transparent battery. Thus the PB/aluminium device we report here is bifunctional, that is, it is a self-powered electrochromic window as well as a self-rechargeable transparent battery.