| 초록 |
We have investigated the effect of blocking layer deposited on a transparent conducting glass (TCO) on photovoltaic performance in dye-sensitized solar cell. Blocking layers are deposited using Ti(IV)bis(ethyl acetoacetato)–diisopropoxide precursor solution, where the concentration of the precursor solution is varied from 0 to 0.4 M. SEM cross section view confirms that the thickness of the blocking layer increases with increasing concentration, in the ranging from 0 to 90 nm. The deposited blocking layer forms anatase phase. Overall conversion efficiency increases with increasing the precursor concentration and reaches maximum at 0.15 M, which is mainly due to increase in photocurrent density. Electrochemical impedance spectroscopy under one sun light illumination shows a new semicircle at high frequency range. Blocking layer at TCO is found to play an important role in protection of back electron transfer from TCO to electrolyte. |
