Double layer photoelectrodes consisting of the TiO 2 nanoparticles (npTiO 2) with 30-40nm in diameter and the TiO 2 nanospheres (nsTiO 2) with 100-200nm as a bottom and a top layer, respectively, were fabricated for dye-sensitized solar cells (DSSCs) employing a polymer electrolyte. The nsTiO 2 with hierarchical pores were prepared via the combined process of atom transfer radical polymerization (ATRP) and a sol-gel. Use of nsTiO 2 resulted in the remarkable enhancement of cell performance due to light scattering and dye adsorption capability. The overall energy conversion efficiency (η) of 5.5% was achieved by the formation of npTiO 2-nsTiO 2 double layer photoelectrode, which was higher than those formed by npTiO 2 alone (4.6%) or nsTiO 2-nsTiO 2 double layer (4.4%). Electrochemical impedance spectra (EIS) analysis showed that the npTiO 2-nsTiO 2 double layer had lower electron transfer resistance and longer electron lifetime, leading to facilitation of reduced recombination and consequently improvement of cell performance.
All Science Journal Classification (ASJC) codes
- Chemical Engineering(all)