Solid-State Dye-Sensitized Solar Cell with p-type Co3O4 as a Hole Conductor

• Main Authors: Weng, Tsu-Heng, 翁子恆
• Other Authors: Yew, Tri-Rung
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/17122450766606983893

碩士 === 國立清華大學 === 材料科學工程學系 === 97 === In this work, through the optimization of temperature, time, concentration, and stirring of chemical the reaction, a hydrothermal synthesis of Co3O4 with unique nanostructure is presented. Using this nanostructured Co3O4 as a hole conductor, a solid-state dye-sensitized solar cell (SS-DSSC) with an inverse stacking sequence of layers is also fabricated. The Co3O4 nanoparticles covered with smaller flakes have been synthesized in an aqueous solution with 25% of ammonia solution in the volume ratio, which is sealed at 85 °C for 24 hr. The as-grown Co3O4 black nanoparticles exhibit a diameter of around 100 nm, and optical band gaps of 3.15 eV and 1.85 eV. Besides, a SS-DSSC utilizing these as-grown Co3O4 nanoparticles as the hole collector with an inverse stacking sequence is fabricated by paste-squeegee method in order to provide better contact between hole Co3O4 conductor and TiO2 layer, higher stability under sunlight, and easier sealing condition than liquid-type dye-sensitized solar cells (DSSCs). Even though the fabricated DSSC devices in this work exhibit low power conversion efficiency (PCE) of 2.6�e10-4 %, major root causes were identified. Further efforts in improving the contact between Co3O4 and TiO2, optimizing the thickness of film stacks, and reducing Co3O4 nanostructure size will enable the fabrication of an SS-DSSC with good stability and power conversion efficiency.