| 초록 |
Since O'Regan and Gratzel announced dye-sensitized solar cells (DSSCs), DSSCs gradually engage society's attention due to their ease of fabrication, low cost, green production process and high efficiency. Furthermore, substantial efforts have been made to fabricate solid-state DSSCs (ssDSSCs) with stable electrolytes. Obtaining fine pore-filling of solid electrolyte into a photoanode is pivotal for high energy conversion efficiency of ssDSSCs. A multi-layered shell is considered to be an effective way to satisfy these conditions as good photoanode. TiO2 has been widely used as a photoanode in DSSCs over the last few decades. However, due to low electron mobility of TiO2, alternative metal oxides such as ZnO, Nb2O5 and SnO2 are considered as substitutes. Especially, SnO2 has a decided advantage since its higher conduction band energy (3.6 eV) and electron mobility. In this study, we report 8.2 % conversion efficiency which is one of the highest values for ssDSSCs. This ssDSSC is based on inner SnO2 hollow sphere (SHS) surrounded by outer TiO2 nanosheets (TNS) which result in improved light scattering, large surface area and excellent electron transport. |
