Application Of Lonic Liquids As Electrolye In Dye-Sensitized Solar Cells

Dye-Sensitized Nano-crystal Solar Cells, or Dye-Sensitized Solar Cells (DSSCs) is a technically and economically reliable substitution for the traditional P-N node photovoltaic unit. Electrolyte plays a significant role in DSSCs, it is the major component to maintain the performance of the cells, which complete the regeneration by the reduction of the dye. DSSC is granted various photoelectric conversion efficiency depending on different electrolyte, thus, stable cells with high performance need special electrolytes. Ionic liquid, known for long-lasting, easy to prepare, nontoxic, odorless and great potential to increase the efficiency, becomes the optimal choice for next generation of DSSC.The major components of ionic liquid (IL) based DSSC electrolytes include:IL iodides, low-viscosity IL solvents and corresponding additive. Several ionic liquids are usually mixed to form a mixture of IL iodides in order to increase entropy and lower viscosity. A mixture of EMâ…¡, DMâ…¡and PMâ…¡were used. Solid DMII and EMâ…¡have the highest entropy when dissolved. EMITA and EMIBF4 were chosen after investigating the properties of many kinds of ionic liquids. The additives such as I2, TBP, LiI and GNCS is commonly used.The aforementioned ionic liquids were synthesized from NMI. New routine was employed when synthesizing EMITA:the direct backflow reaction of EMIBr (or EMâ…¡) with TFA. This product has high purity and the elementary iodine is recyclable. The most advantage of this routine is the low cost, avoiding the use of expensive, unstable silver salts.7 different types of IL electrolytes were made with the synthesized IL compounds and proper additives. Stoichiometry I did not give a liquid state, it could be because the high proportion solid material in components and the common ion effect of EMI+ further stimulates this insolubility. The rest stoichiometry all yielded liquid material with good mobility. The electrolyte was assembled in DSSC cell, the performance was tested with an electrochemistry workstation and professional software LK9805 was used to plot J-V curve. By comparison, the most effective stoichiometry isâ…¦, the efficiency approached 5%, it could be further enhanced and possessed a great potential in application.