Dye-sensitized solar cells fabricated by electrospray coating using TiO2 nanocrystal dispersion solution

Dye-sensitized solar cells (DSCs) were fabricated by an electrospray coating method using TiO2 nanocrystal dispersion (P25) in water (DSC-ESC). They were compared with DSCs prepared by conventional coating methods (DSC-COAT). The former had higher short-circuit current (J(SC)) than the latter. Electron lifetime and electron diffusion coefficient in TiO2 layers did not vary largely between the two DSCs. Large differences were not observed between them in terms of the amount of dye molecules adsorbed on TiO2. Differences were observed only for limiting currents (I-3(-) diffusion) through TiO2 layers. The limiting current for DSC-ESC was higher than that of DSC-COAT. Considering the previous reports on fractal structures prepared by the ESC method and the fact that needle-like TiO2 tends to grow on deposited TiO2 needles by using the ESC method, we conclude that ionic paths are formed better in TiO2 layers of DSC-ESC than in those of DSC-COAT. (c) 2006 The Electrochemical Society.