Fabrication and Characterization of Solid-State Dye Sensitized Solar Cells Incorporating Hydroxy-attached Ruthenium Dye and Carbon Nanotubes

• Main Authors: Chiao-Yueh Lo, 羅喬嶽
• Other Authors: King-Fu Lin
• Format: Others
• Language: en_US
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/97121515103814060711

碩士 === 國立臺灣大學 === 材料科學與工程學研究所 === 101 === This research is divided in three parts: 1. fabrication optimization of the solid-state dye sensitized solar cells (SSDSSCs), 2. application of hydroxyl-substituted ruthenium dye on SSDSSCs and 3. incorporating MWCNTs in TiO2 working electrode for SSDSSCs . We first carried out the fabrication optimization of SSDSSCs by adjusting the compact layer and nanoporous layer thickness. The thickness of each layer was controlled by varying the concentration of precursor solution. The optimized processing parameters matches those reported in the literatures. In the second part, we have synthesized a hydroxy-substituted dye, denoted as RuC1OH. SSDSSCs sensitized with RuC1OH were fabricated and characterized. The SSDSSCs based on RuC1OH performed both higher open-circuit voltage and short-circuit current compared to N3 based devices. The power conversion efficiency (PCE) reached 1.01%. Photovoltaic properties were characterized by electrochemical impedance spectroscopy (EIS), IMPS/IMVS, photovoltage decay, and charge collection techniques. The surface properties of TiO2 and hole-transport material infiltration were studied by contact angle measurements and SEM, respectively. The photovoltaic property improvement can be attributed to higher affinity between RuC1OH sensitized TiO2 and hole-transport material (HTM), which lead to better HTM infiltration into nanoporous TiO2. In the third part, MWCNTs were surface-modified by NaPSS and added to the nanoporous TiO2. According to XRD results, the anatase phase of TiO2 increased when MWCNT was added. We observed that more anatase phase benefits photovoltaic properties of SSDSSCs. Although the open-circuit voltage decreased with the addition of MWCNT, it was compensated by higher short-circuit current and higher fill factor. The PCE increased from 0.75% to 0.94%. The device properties were further characterized by EIS and IMPS/IMVS, and the results showed that both recombination rate and charge transfer rate were increased. In summary, the TiO2 surface properties can be tuned by different sensitizers, which is important for improving HTM pore-filling. We also found out that introducing MWCNTs could improve the PCE of SSDSSCs.