Application of highly efficient thixotropic polysulfide electrolyte in QDSSCs

• Main Authors: Yu-Hsuan Chen, 陳妤瑄
• Other Authors: Jia-Yaw Chang
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/8zyb9h

碩士 === 國立臺灣科技大學 === 化學工程系 === 106 === Despite to the higher power conversion efficiencies of quantum dot sensitized solar cells (QDSSCs), photovoltaic devices that employ liquid electrolytes suffer from problems like long-term instability caused by leakage and volatilizations of electrolytes. In this study, to improve the stability, sealing, and conversion efficiency of the liquid-junction QDSSCs, an alternative electrolyte, gel electrolytes using organic polymer and inorganic nanoparticle (NP) gelators was attempted. Herein, we developed a noble water-based polymer gel electrolyte utilizing Xanthan gum (XG), which has thixotropic property, higher water solubility and environmentally friendly. Owing to the lower mobility of electrons in the liquid-junction TiO2 NPs was added which can improve ion conductivity and charge transfer. The charge recombination at the photoanode/electrolyte interface was emarkably inhibited with the addition of XG and TiO2 NP to the polysulfide electrolyte. Additionally, incorporation of TiO2 NPs increases VOC by adjusting photoanode fermi level. With our best condition XG/NP electrolyte, the efficiency of CIS-based QDSSCs was improved from 6.48 ± 0.15% to 7.06 ± 0.06%. And the efficiency of CISe-based QDSSCs was improved from 6.79 ± 0.10% to 8.00 ± 0.21%. To the best of our knowledge, this is the highest efficiency based on water-based XG/TiO2 electrolytes for CIS and CISe QDSSCs.