Fine-Tuning of TiO2 Nanofibers-Mixed Nanoparticles-Photoelectrode for High Efficient Dye-Sensitized Solar Cells

Abstract

Electrospun TiO2 nanofibers were fabricated as a layer of photoelectrode for dye-sensitized solar cells (DSCs). TiO2 nanofibers were fabricated by using sol-gel and electrospinning techniques from mixed solution of titanium butoxide, acetylacetone, and polyvinylpyrrolidone (PVP) in methanol. Calcination of the composite fibers at 450åC for 3 h resulted in predominant content of anatase titania nanofibers. The obtained TiO2 nanofibers showed one-dimensional structure with the diameters about 100-200 nm. These nanofibers were applied to construct the dye (N719) sensitized photoelectrochemical cells with the combination of TiO2 nanoparticles in both original fiber form and nanorods from mechanical grinding of nanofibers. When the TiO2 nanofibers were combined to nanoparticles, enhanced photovoltaic performance was attained as compared with conventional TiO2 nanoparticles. TiO2 nanorods were fabricated by mechanical grinding of electrospun nanofibers and were applied to utilize DSCs. The optimization of thickness of TiO2 nanorods-mixed nanoparticles-photoelectrode was also investigated.