Effect of the preparation procedure on the morphology of thin TiO₂ films and their device performance in small-molecule bilayer hybrid solar cells.
Flat titanium dioxide films, to be used as the acceptor layer in bilayer hybrid solar cell devices, were prepared by spray-pyrolysis and by spin-casting. Both preparation methods resulted in anatase titania films with similar optical and electronic properties but considerably different film morphologies. Spray pyrolysis resulted in dense TiO₂ films grown onto and affected by the surface roughness of the underlying conducting glass substrates. The spin-casting preparation procedure resulted in nanoporous titania films. Hybrid solar cell devices with varying layer thickness of the small-molecule semiconducting dye TDCV-TPA were investigated. Devices built with spray-pyrolyzed titania substrates yielded conversion efficiencies up to 0.47%. Spin-cast titania substrates exhibited short circuits for thin dye layer thickness. For thicker dye layers the performance of these devices was up to 0.6% due to the higher interfacial area for charge separation of these nanoporous TiO₂ substrates.
Department of Chemistry-Ångström Laboratory, Uppsala University, Box 523, 75120 Uppsala, Sweden.
Eva L
EL
Unger
Francesca
F
Spadavecchia
Kazuteru
K
Nonomura
Pål
P
Palmgren
Giuseppe
G
Cappelletti
Anders
A
Hagfeldt
Erik M J
EM
Johansson
Gerrit
G
Boschloo
D003460:Crystallization / Q000379:methods; D011211:Electric Power Supplies; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008567:Membranes, Artificial; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D036103:Nanotechnology / Q000295:instrumentation*; D010316:Particle Size; D012993:Solar Energy; D014025:Titanium / Q000737:chemistry*
D008567:Membranes, Artificial; C009495:titanium dioxide; D014025:Titanium