Preparation of a nanoporous CaCO3-coated TiO2 electrode and its application to a dye-sensitized solar cell.
A nanoporous CaCO3 overlayer-coated TiO2 thick film was prepared by the topotactic thermal decomposition of Ca(OH)2, and its performance as an electrode of a dye-sensitized solar cell was investigated. As compared to bare TiO2, nanoporous CaCO3-coated TiO2 provided higher specific surface area and, subsequently, a larger amount of dye adsorption; this in turn increased short-circuit current (Jsc). Furthermore, the CaCO3 coating demonstrated increased impedance at the TiO2/dye/electrolyte interface and increased the lifetime of the photoelectrons, indicating the improved retardation of the back electron transfer, which increases Jsc, open-circuit voltage (Voc), and fill factor (ff). Thereby, the energy conversion efficiency (eta) of the solar cell improved from 7.8 to 9.7% (an improvement of 24.4%) as the nanoporous CaCO3 layer was coated onto TiO2 thick films.
Lee
Sangwook
S
School of Materials Science and Engineering, Seoul National University, San 56-1, Shillim-dong, Kwanak-gu, Seoul 151-744, South Korea.
Kim
Jin Young
JY
Youn
Sung Hun
SH
Park
Min
M
Hong
Kug Sun
KS
Jung
Hyun Suk
HS
Lee
Jung-Kun
JK
Shin
Hyunho
H