ZnO Nanowires as Photoanode Material for Quasi-Solid State Dye-Sensitized Solar Cells

• Main Authors: Huang, Po-Yung, 黃博雍
• Other Authors: Lin, Heh-Nan
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/84632239284917085296

碩士 === 國立清華大學 === 材料科學工程學系 === 98 === In recent years, much attention has been paid to the development of dye-sensitized solar cells (DSCs) because of their low production cost. In this study, the growth of well-aligned single-crystalline ZnO nanowires (NWs) is realized on bare transparent conductive oxide (TCO) glass substrates by thermal evaporation. Although the NWs provide a good electron transport path, the surface area of the NWs is too small for dye loading. In this study, additional ZnO NWs for backbones of branched NWs were added and a secondary growth was introduced to raise the surface area of the photoanode and enhance the light scattering effect. The Short-circuit current density(JSC) was improved to 5.38 mA/cm2 for the branched NW photoanode from 4.07 mA/cm2 for the bare NW photoanode. The highest conversion efficiency and the fill factor were around 1.57% and 0.50, respectively. On the other hand, liquid electrolytes are usually used in DSCs, rendering leakage and evaporation problems. To solve these problems, solid-state hole transporters, whether organic or inorganic, polymer electrolytes and gel polymer electrolytes have been used to replace liquid electrolytes in many reports. A gel electrolyte with good contact, reasonable conductivity, ease of fabrication, was prepared to make quasi-solid state DSCs. The highest efficiency of 0.7% and the fill factor of 0.54 have been achieved. In comparison with DSCs with liquid electrolytes, the relative low JSC and the efficiency are due to the lower ion diffusion velocity.