Designed Architecture of Multiscale Porous TiO2 Nanofibers for Dye-Sensitized Solar Cells Photoanode

Multiscale porous (MSP) TiO2 nanofibers (NFs) were fabricated using a simple electrospinning and etching process with TiO2/SiO2 composite NFs for high-efficiency dye-sensitized solar cells (DSSCs). TiO2 NFs with different pore sizes (small, large, and multiscale) were prepared using SiO2 nanoparticles of various sizes. The surface area of the MSP TiO2 NFs was nine times higher than that of pristine MSP TiO2 NFs, providing sufficient dye adsorption for light harvesting as well as efficient paths for electrolyte contact. Moreover, the one-dimensional structure provides efficient light scattering and fast electron transport. As a result, DSSCs exhibited an enhanced current density (J(sc)) of 16.3 inA cm(-2) and a high photoconversion efficiency (eta) of 8.5%, greater than those of conventional photoelectrodes made of TiO2 nanoparticles (J(sc) of 12.0 mA cm(-2) and eta of 6.0 %).