Processing of Printed Dye Sensitized Solar Cells on Woven Textiles

Abstract

This paper presents the novel use of screen printing and spray coating techniques to fabricate dye sensitized solar cells on textiles for wearable energy harvesting applications. Multiple functional layers of electrodes and active materials have been deposited on everyday use polyester cotton woven fabric and high-temperature resistant glass fiber fabric. The poly cotton fabric limits processing temperatures to 150 °C, while the glass fiber textile can withstand up to 1200 °C. The surface roughness of the textiles has been significantly reduced by screen printing a polyurethane interface layer on the polyester cotton fabric and a liquid polyimide on the glass fiber textile. A silver bottom electrode layer and a bespoke titanium dioxide electron transport layer formulated for each temperature range were then screen printed onto the planarized surfaces. The devices use Iodine/Iodide (I <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-</sup> /I <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-</sup> ) as the liquid electrolyte and were sealed with a plastic PET/ITO, which also forms the counter electrodes. The printed cells have demonstrated photovoltaic (PV) power conversion efficiencies of 3.24% on polyester cotton and 4.04% on glass fiber textiles, in ambient conditions. The polyurethane and polyimide interface layers significantly enhance the performance and stability of the fabricated cells providing extended operational lifetimes. This approach is potentially suitable for the low-cost integration of PV devices into clothing and other textile applications.