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The present work describes the preparation and characterization of PEDOT films (different commercial screen-printing grades) mixed with intrinsically conductive materials such as graphene, graphite, silver nanowires or AZO (antimony doped zinc oxide) deposited on plastic and paper substrates using screen-printing. The final objective was to develop a material that could be used both as electrochromic material and as electrode (electrically conductive) for use in electrochromic devices, avoiding the use of an extra layer of conductive material such as a TCO, allowing the use of different substrates, shapes or sizes, because of the limitations found in TCO deposition. The resulting films were characterized in terms of electrical and optical properties, as well as electrochemical stability. Techniques such as cyclic voltammetry, UV–visible spectroscopy, scanning electron microscopy and mechanical tests were also used. Electrochromic devices (ECDs) were assembled using these PEDOT based electrodes. The performances of the resulting devices (3 layer structures) were compared with that of conventional ones (5 layer structures) through the analysis of the device color contrast over time during continuous operation conditions using a cycling program. [ABSTRACT FROM AUTHOR]

Low-cost electrochromic devices presenting fast switching continue to have an enormous interest for industrial applications; however the durability of the devices is a parameter of critical importance. The present work describes the preparation and characterization of ITO free electrochromic devices, being the use of hybrid electrodes for low-cost electrochromic devices the main focus. It was used silver grids (silver ink) as electrically conductive electrodes. These grids were screen-printed on polyethylene terephthalate (PET), using two different patterns and different line widths. The printing of a conductive polymer film on top of the grids for electrochemical protection of the metal was evaluated. These grids were characterized in terms of equivalent resistance and light transmission, considering each pattern, as well as electrochemical stability. The resulting electrochromic devices were tested using cyclic voltammetry, spectroelectrochemistry and colorimetry. The durability of the devices was characterized through the analysis of color contrast over time during continuous operation conditions using a cycling program. These experiments displayed electrochromic devices performing 100 cycles before degradation with switching times of 4.5 s and a color contrast (Δ E ) of 27 or a variation in transmittance of 50% between redox states. [ABSTRACT FROM AUTHOR]