The study of electrochromic materials for viewports with dynamic shadowing implementation

Аuthors

Zhidik Y. S.^*, Troyan P. E.^**, Voronyuk E. E.^***

Tomsk State University of Control Systems and Radioelectronics, 40, Lenin str., Tomsk, 634050, Russia

*e-mail: zhidikyur@mail.ru
**e-mail: p.e.troyan@mail.ru
***e-mail: lightofnight93@rambler.ru

Abstract

The purpose of this work is to study and compare the characteristics of electrochromic devices based on inorganic materials, such as WO₃ и Fe₄(Fe(CN)₆)₃ for using in passenger cabin viewports with dynamic shadowing.

The study of various electrochromic devices structural variants based on these materials revealed that the structure configuration based on Fe₄(Fe(CN)₆)₃ allowed obtain the most effective result. Moreover, device characteristics such as the transition time to colored state and the transmittance in the bleached state deteriorate with increasing thickness of the electrochromic layer due to deceleration Fe3+ ions reduction to Fe2+ ions. The optimal variant of electrochromic device was the device with the electrochromic coating thickness of 400 nm, which transmittance in the visible range varies from 68 to 21% when the potential difference of 1.5 V was applied for 3 seconds. With the electrolyte concentration increase, the coloring / bleaching time was found to be increased due to reduced velocity of the ions, caused by the increase of the Coulomb interaction between the ions of the electrolyte. The best coloring / bleaching time was obtained by using 1 M KCl solution.

Ease of operation, low power consumption, and high-speed dimming should be noted when such devices are implemented for passenger cabin portholes dynamic shadowing. The major shortcoming of inorganic electrochromic devices today is the limited number of coloring / bleaching cycles. Due to this, the inorganic electrochromic devices are almost completely ousted from the market by electrochromic devices based on liquid crystals and polymers (Pdlc). A disadvantage of the devices based on liquid crystals (Pdlc) is that they have only two states: fully transparent and fully shadowed, which eliminates the continuous adjustment of the device. Thus, electrochromic devices based on inorganic materials have a great potential for development and competition in the market of electrochromic devices, one of which is passenger cabin portholes with dynamic shadowing.

Keywords:

aviation materiel, thin-film coating, tungsten trioxide, Prussian blue, electrochromic device

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