Improvement of Dye Sensitized Solar Cells With Nanofiber-Based Anode Available to Purchase

Dye Sensitized Solar Cell (DSSC) has great advantages over conventional silicon-based photovoltaics as it is inexpensive, flexible, and transparent. Sun energy is used to excite the electron of the organic (ruthenium-polypyridine) dye from which the electron from the dye is injected into the anode made of titanium dioxide (TiO₂). The excited electron enters the conduction band of the TiO2 and gets transmitted across the TiO2 nanoparticles (anode) to the FTO (Fluorine-doped tin-oxide) glass/electrode, which in turn go to the external circuit powering the electrical load. The electron returns to the device via the counter electrode coated with a platinum catalyst to the electrolyte, typically iodide/tri-iodide, wherein the iodide ions carry the electron back to regenerate the dye attached to the TiO₂ nanofibers. Improvement can be made by using 60–120 nm diameter TiO₂ nanofibers produced in our lab, for which electrons can be directly transferred to the FTO reducing the recombination rate. Also, the large surface-to-volume ratio of the nanofibers allows numerous sites for attachment of the organic dye molecules, thereby increasing the capture of sunlight. In order to achieve high conversion efficiency, several critical parameters need to be optimized with the nanofiber-based DSSC. In this study, we investigate the thickness of the anode (TiO₂ nanofiber) on the conversion efficiency. The conversion efficiency of the DSSC in our laboratory can reach more than 7%. Other improvements are believed to further boost this efficiency.