TY - JOUR AB - In the context of the energy transition to renewables, the spotlight is on large systems connected to the power grid, but this also offers room for smaller, more specialized applications. Photovoltaics, in particular, offer the possibility of the self-sufficient supply of smaller electrical appliances on smaller scales. The idea of making previously unused surfaces usable is by no means new, and textiles such as backpacks, tent tarpaulins and other covers are particularly suitable for this purpose. In order to create a non-toxic and easily recyclable product, dye-sensitized solar cells (DSSC), which can be manufactured through electrospinning with a textile feel, are an attractive option here. Therefore, this paper investigates a needle electrospun nanofiber mat, whose spin solution contains polyacrylonitrile (PAN) dissolved in dimethyl sulfoxide (DMSO) as well es TiO2 nanoparticles. In addition to characterization, the nanofiber mat was dyed in a solution containing anthocyanins to later serve as a front electrode for a dye-sensitized solar cell. Although of lower efficiency, the DSSC provides stable results over two months of measurement. AU - Dotter, Marius AU - Placke, Lion Lukas AU - Storck, Jan Lukas AU - Güth, Uwe ID - 2577 IS - 4 JF - Tekstilec KW - dye-sensitized solar cells (DSSC) KW - long-term stability KW - electrospinning KW - polyacrylonitrile (PAN) KW - TiO2 nanoparticles SN - 0351-3386 TI - Characterization of PAN-TiO2 Nanofiber Mats and their Application as Front Electrodes for Dye-sensitized Solar Cells VL - 65 ER - TY - JOUR AB - Polyacrylonitrile belongs to the most often used precursors for carbon fibers. Using electrospinning, polyacrylonitrile nanofiber mats can be prepared and afterwards stabilized and carbonized to prepare carbon nanofiber mats which, by adding other materials, will be useful for several applications. One of these materials is TiO2, which has photocatalytic properties and can thus be used as a photocatalyst for photodegradation of dyes. Here, we report on a detailed study of electrospinning, stabilization, and carbonization of electrospun polyacrylonitrile/TiO2 mats with varying TiO2 content. Depending on the amount of TiO2 in the nanofibers, the fiber morphology changes strongly, indicating an upper limit for the preparation of carbon/TiO2 nanofibers with smooth surface, but offering an even increased inner surface of the rougher carbon/TiO2 nanofibers with increased TiO2 content due to better maintenance of the fibrous structure during stabilization. AU - Sabantina, Lilia AU - Böttjer, Robin AU - Wehlage, Daria AU - Grothe, Timo AU - Klöcker, Michaela AU - García-Mateos, Francisco José AU - Rodríguez-Mirasol, José AU - Cordero, Tomás AU - Ehrmann, Andrea ID - 573 JF - Journal of Engineered Fibers and Fabrics KW - Polyacrylonitrile KW - PAN KW - TiO2 KW - nanofiber mat KW - electrospinning KW - composite KW - stabilization KW - carbonization TI - Morphological study of stabilization and carbonization of polyacrylonitrile/TiO2 nanofiber mats VL - 14 ER - TY - JOUR AB - Developing dye-sensitized solar cells (DSSCs) further is of utmost importance in a time of increasing energy consumption and the necessity to change to renewable energy sources. Opposite to silicon-based solar cells, DSSCs can be produced from low-cost, non-toxic materials. In addition, they can be applied on flexible substrates, enabling even utilization on textile architecture. On the other hand, reaching efficiencies in a similar order of magnitude as with silicon-based solar cells is only possible by highly pure and toxic materials. This is why optimization of DSSCs with non-toxic and affordable materials is of high interest. Here we report on the possibility to increase the TiO2 layer performance by adding a nonionic surfactant, focusing on a non-toxic electrolyte and a natural dye. Our results show that coating the semiconducting layer from a solvent including a surfactant increases the efficiency of the DSSC. To enable comparison with results of other groups which are often reported for very small active areas, we compare three different areas between 0.25 cm² and 6.0 cm² and show that the efficiencies are more than doubled for the smallest active area in comparison to the largest one. This underlines the necessity to perform more research on large-area DSSCs, e.g. by combining several smaller cells, aiming at possible applications on tents or other large textile areas. AU - Udomrungkhajornchai, Suphawit AU - Junger, Irén Juhász AU - Ehrmann, Andrea ID - 622 JF - Optik KW - Dye-sensitized solar cells (DSSCs) KW - Semiconductor KW - TiO2 KW - Nonionic surfactant KW - Triton X-100 KW - Natural dye KW - Anthocyanin KW - Active area SN - 0030-4026 TI - Optimization of the TiO2 layer in DSSCs by a nonionic surfactant VL - 203 ER - TY - JOUR AB - TiO2 is a semiconductor that is commonly used in dye-sensitized solar cells (DSSCs). However, the necessity of sintering the TiO2 layer is usually problematic due to the desired temperatures of typically 500 °C in cells that are prepared on polymeric or textile electrodes. This is why textile-based DSSCs often use metal fibers or metallic woven fabrics as front electrodes on which the TiO2 is coated. Alternatively, several research groups investigate the possibilities to reduce the necessary sintering temperatures by chemical or other pre-treatments of the TiO2. Here, we report on a simple method to avoid the sintering step by using a nanofiber mat as a matrix embedding TiO2 nanoparticles. The TiO2 layer can be dyed with natural dyes, resulting in a similar bathochromic shift of the UV/Vis spectrum, as it is known from sintered TiO2 on glass substrates, which indicates an equivalent chemical bonding. Our results indicate a new possibility for producing textile-based DSSCs with TiO2, even on textile fabrics that are not high-temperature resistant. AU - Ehrmann, Andrea AU - Mamun, Al AU - Trabelsi, Marah AU - Klöcker, Michaela AU - Sabantina, Lilia AU - Großerhode, Christina AU - Blachowicz, Tomasz AU - Grötsch, Georg AU - Cornelißen, Carsten AU - Streitenberger, Almuth ID - 570 IS - 7 JF - Fibers KW - TiO2 KW - dye-sensitized solar cell (DSSC) KW - textile-based DSSC KW - electrospinning KW - nanofiber mat KW - polyacrylonitrile (PAN) TI - Electrospun nanofiber mats with embedded non-sintered TiO2 for dye-sensitized solar cells (DSSCs) VL - 7 ER -