Application Of Solid-State Electrolytes Dye Sensitized Solar Cells Based On Organic Ionic Plastic Crystals

Dye-sensitized solar cells （DSSCs） have been considered as an ideal alternative tosilicon photovoltaic cells and attracted a great deal of attention because of their relativelyhigh energy conversion efficiency and low production cost. Electrolytes play an importantrole in DSSC. Although the overall power conversion efficiency of more than12%hasbeen achieved for DSSCs with the liquid electrolyte, there are still some scientific andtechnological difficulties should be overcome before the widespread commercialization ofDSSCs. For example, the solvent leakage of the liquid electrolyte-based DSSCs increasesthe difficulty in sealing the device and reduces the long-term stability of cells.In this work, ionic organic plastic crystals were used as a new class of flexible organicsolid ion conductive materials because of their unique small molecules plastic strength andgood performance of the rapid transmission of the doped ion. Main contents andconclusions contained two parts as follows.1. Organic ionic plastic crystals P₁₂I was synthesized and characterized by NMR,DSC, TGA. The organic ionic plastic crystal matrix was doped I2and different amounts ofPMII to prepare the plastic crystal solid electrolyte which can be used in DSSCs, and aseries of test were studied, including conductivity, thermal properties, ion diffusioncoefficient. Finally, the fabricated solid–state devices give an overall power conversionefficiency of about5.8%at80°C under simulated radiation （50mW/cm²）. Furthermore,DSSCs based on PMII doped P₁₂I ionic plastic crystal electrolyte show excellent long–timestability at80°C. These results demonstrate a feasible approach to solid–state DSSCs forpractical outdoor application at high temperatures.2Organic ionic plastic crystals P₁₂TFSI was synthesized and characterized by NMR,DSC, TGA. The organic ionic plastic crystal matrix was doped I2and PMII to prepare theplastic crystal solid electrolyte which can be used in DSSCs, and a series of test werestudied, including conductivity, thermal properties, ion diffusion coefficient. Finally, theorganic ionic plastic crystal based solid electrolytes have been employed to fabricate solid-state DSSCs, without using any volatile solvent. The cells with the solid-stateelectrolytes showed maximum efficiency of5.12%under the simulated air mass1.5solarspectrum illumination at50mW cm^-2, as well as superior long-term stability, whichindicated that the solid-state DSSCs based on this type of electrolytes could overcome theleakage problem of devices with liquid electrolyte.