Textile-based dye-sensitized solar cells (DSSCs) can be created by building the necessary layers on a textile fabric or around fibers which are afterwards used to prepare a textile layer, typically by weaving. Another approach is using electrospun nanofiber mats as one or more layers. In this work, electrospun polyacrylonitrile (PAN) nanofiber mats coated by a conductive polymer poly(3,4-ethylenedioxythiopene) polystyrene sulfonate (PEDOT:PSS) were used to produce the counter electrodes for half-textile DSSCs. The obtained efficiencies were comparable with the efficiencies of pure glass-based DSSCs and significantly higher than the efficiencies of DSSCs with cotton based counter electrodes. The efficiency could be further increased by increasing the number of PEDOT:PSS layers on the counter electrode. Additionally, the effect of the post treatment of the conductive layers by HCl, acetic acid, or dimethyl sulfoxide (DMSO) on the DSSC efficiencies was investigated. Only the treatment by HCl resulted in a slight improvement of the energy-conversion efficiency.

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Electrochromic devices can act as passive displays. They change their color when a low voltage is applied. Flexible and bendable hybrid textile-film electrochromic devices with poly-3,4-ethylenedioxythiophene polystyrene sulfonate (PEDOT:PSS) were prepared on polyethylene polyethylene terephthalate (PEPES) membranes using a spray coating technique. The electrolyte consisted of a gelatin glycerol mixture as host matrix and calcium chloride. Titanium dioxide was used as an ion storage layer and a carbon containing dispersion was used for the counter electrode on a polyester rip-stop fabric. The sheet resistance of PEDOT:PSS on PEPES was 500 Ohm/sq. A 5 × 5 electrochromic matrix with individually addressable pixels was successfully designed and assembled. The switching time of the pixels was 2 s at a voltage of 2.0 V directly after assembling. The use of titanium dioxide as ion storage also increased the contrast of the dark-blue reduced electrochromic layer. Coloration was not self-sustaining. The PEDOT:PSS layer needed a constant low voltage of at least 0.5 V to sustain in the dark-blue reduced state. The switching time increased with time. After 12 months the switching time was ~4 s at a voltage of 2.8 V. The addition of glycerol into the electrolyte extended the lifetime of a non-encapsulated textile electrochromic cell, because moisture is retained in the electrolyte. Charge carriers can be transported into and out of the electrochromic layer.

Polyvinyl butyral is used in safety glass interlayers, mainly in car windshields. Legislative regulations require a recycling of cars after their lifetime and therefore also their safety glass. This causes the availability of recycled polyvinyl butyrate (r-PVB) originated from safety glass interlayers. Due to deteriorated optical properties, such as the transparency, and unknown amounts of plasticizers, it is challenging to reuse the recycled material in new windshields. Therefore, it is of particular interest to find new fields of application for r-PVB, such as the usage as a textile coating. In this research, r-PVB was investigated as a material for yarn coating. Polyester and polyamide mono- and multifilament yarns were coated continuously with solely a polymer dispersion and with mixtures of crosslinking agent and polymer dispersion. Crosslinked r-PVB coatings showed enhanced properties toward abrasion and chemical resistance. Coatings without the crosslinking agent showed a diminished abrasion resistance and could be washed off with ethanol. Mechanical properties of the monofilaments were influenced by the r-PVB coating in general. However, varying concentrations of the crosslinking agent did not affect the mechanical properties.

Alternating current–driven electroluminescent devices on polyester fabrics were realized using a combination of coating and printing. The PEDOT:PSS front electrode was coated onto the fabric using knife coating. All other layers were digitally printed using a specially modified three-dimensional printer and three-dimensional printing software. Slicing parameters (line distance, printing speed, printing pattern) as well as other hardware parameters and ink viscosity were evaluated for each ink to obtain a good print. Final results show a complex interaction of all investigated parameters. Fully digitally printed electroluminescent devices show a luminescence of 44 lx, but combinations of digital printing and knife coating show a much higher luminescence of up to 128 lx for samples with an even smaller luminous layer thickness.

Alternating-current (AC) electroluminescent (EL) devices on fabrics with high brightness are presented. The EL-devices were fabricated via knife coating; inorganic luminous pigments are based on zinc sulfide. Effects of parameters influencing the brightness were investigated. These parameters are the AC-voltage, AC-frequency, AC-waveform, layer composition of the luminous capacitor and the fabric. Introducing a flexible reflecting dielectric layer enhances the light yield on fine woven fabrics with green luminous pigment. This can be achieved with small concentrations of reflective white pigments such as titanium dioxide, maintaining the flexibility and bendability of the textile substrate. The produced luminous textiles are investigated as a possible replacement for light boxes used in the therapy of seasonal affective disorder (SAD). A high luminous emittance and a high portion of short and energy rich wavelengths are necessary for the treatment. Contrarily to state-of-the-art light boxes a higher acceptance of light therapy is expected, because a luminous textile can be integrated easily and unremarkably into the living environment.

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