High-performance large-scale flexible dye-sensitized solar cells based on anodic TiO2 nanotube arrays.
A simple strategy to fabricate flexible dye-sensitized solar cells involves the use of photoanodes based on TiO2 nanotube (TNT) arrays with rear illumination. The TNT films (tube length ∼35 μm) were produced via anodization, and sensitized with N719 dye for photovoltaic characterization. Pt counter electrodes of two types were used: a conventional FTO/glass substrate for a device of rigid type and an ITO/PEN substrate for a device of flexible type. These DSSC devices were fabricated into either a single-cell structure (active area 3.6×0.5 cm2) or a parallel module containing three single cells (total active area 5.4 cm2). The flexible devices exhibit remarkable performance with efficiencies η=5.40% (single cell) and 4.77% (parallel module) of power conversion, which outperformed their rigid counterparts with η=4.87% (single cell) and 4.50% (parallel model) under standard one-sun irradiation. The flexible device had a greater efficiency of conversion of incident photons to current and a broader spectral range than the rigid device; a thinner electrolyte layer for the flexible device than for the rigid device is a key factor to improve the light-harvesting ability for the TNT-DSSC device with rear illumination. Measurements of electrochemical impedance spectra show excellent catalytic activity and superior diffusion characteristics for the flexible device. This technique thus provides a new option to construct flexible photovoltaic devices with large-scale, light-weight, and cost-effective advantages for imminent applications in consumer electronics.
Department of Applied Chemistry and Institute of Molecular Science, National Chiao Tung University , Hsinchu 30010, Taiwan.
Hsiu-Ping
HP
Jen
Meng-Hung
MH
Lin
Lu-Lin
LL
Li
Hui-Ping
HP
Wu
Wei-Kai
WK
Huang
Po-Jen
PJ
Cheng
Eric Wei-Guang
EW
Diau
D004396:Coloring Agents / Q000737:chemistry; D058266:Dielectric Spectroscopy; D004566:Electrodes; D004581:Electronics; D043942:Nanotubes / Q000737:chemistry*; D012993:Solar Energy; D014025:Titanium / Q000737:chemistry*
D004396:Coloring Agents; C009495:titanium dioxide; D014025:Titanium