| 초록 |
TiO2 films were modified by adding a glass frit as a light scattering particle and applied to an anode electrode in dye-sensitized solar cells (DSSCs) to enhance the adhesion between TiO2 and fluorine doped transparent oxide (FTO). Low melting point glass frits at contents of (3 to 7wt%) were added to the nano crystalline TiO2 films. The light scattering properties, photovoltaic properties and microstructures of the photo electrodes were examined to determine the role of the low glass transition temperature (Tg) glass frit. Electrochemical impedance spectroscopy, Brunauer-Emmett-Teller method and scratch test were conducted to support the results. The DSSC with the TiO2 film containing 3wt% low Tg glass frit showed optimal performance (5.1%, energy conversion efficiency) compared to the TiO2-based one. The photocurrent density slightly decreased by adding 3wt% of the frit due to its large size and non conductivity. However, the decrease of current density followed by the decrease of electron transfer due to the large frit in TiO2 electrode was compensated by the scattering effect, high surface area and reduced the electron transfer impedance at the electrolyte-dye-TiO2 interface. The stability of the photo electrodes was improved by the frit, which chemically promoted the sintering of TiO2 at relatively low temperature (450oC). |
