| 초록 |
We have investigated the Quantum dot-sensitized solar cells (QDSSCs) using CdSe, CdS, and ZnS onto mesoporous metal oxide. The semiconductor CdSe QD used as a dye in DSSC is prepared over mesoporous TiO2 by successive ionic layer adsorption and reaction (SILAR) process. The growth of the QDs was monitored by UV-visible absorption spectroscopy and scanning electron microscopy (SEM). We prepared TiO2/CdSe/CdS solar cells to introduce a cascade of QD band gaps to facilitate the dissociation of photo-generated excitons in CdSe QDs. By using the CdS under-layer and the ZnS upper-layer, the overall performance of the cell is improved due to ZnS upper-layer blocking back transfer of electrons toward electrolyte. Also titanium(Ⅳ) isopropoxide (TIP) layer was introduced under mesoporous TiO2 layer as a blocking layer for improving the performance of the cell, especially photocurrent and open-circuit voltage. |
