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New dye-sensitized solar cell from the University of Tokyo with a conversion efficiency of 10.3% – April 1, 2009: A research team from the University of Tokyo has developed a dye-sensitized solar cell that uses clay as the electrolyte medium, and has confirmed that its conversion efficiency is as high as 10.3%. This was presented at the 89th Spring Meeting of the Japanese Chemical Society (March 27–30, 2009). The solar cell in question was developed by a research team led by Professor Hiroshi Segawa from the Center for Advanced Science and Technology at the University of Tokyo, along with Associate Professor Satoshi Uchida from the same center. The electrolyte used in solar cells is a substance obtained by adding a type of clay to solutions that include lithium iodide and iodine, and then mixing them uniformly. The clay is “Synthetic Montmorillonite STN” produced by Co-Op Chemical. Also known as “organicized layer clay minerals” (nanoclay). After being mixed with ions, it can be turned into a liquid by applying stresses such as vibration; after being left for a while, it turns into a solid mass (gel), exhibiting \"thixotropy\". The electrode on the light-receiving side (the anode) is made of FTO, and a titanium oxide (TiO2) film with a thickness of 18 μm is formed on this electrode. Additionally, as a dye-sensitized solar cell, it was also coated with the dye “N719” composed of ordinary ruthenium complexes. By changing the weight ratio of clay in the electrolyte and analyzing the properties of the solar cell, it was found that a conversion efficiency of 10.3% can be achieved when the weight ratio is around 10%. Clay is added to the electrolyte to solidify it, thereby addressing the liquid leakage problem that often occurs in dye-sensitized solar cells. It turns out that the material used to solidify electrolytes faces the issue of low conversion efficiency due to the unstable movement of ions, which are the main carriers of charge. The conversion efficiency of 10.3% this time is the same as that when a liquid electrolyte is used.