Inexpensive photovoltaic solar cells remain elusive, especially when considering those based on dye-coated titanium dioxide. These devices are less efficient than silicon based PV cells but would have several advantages if only the electrolyte problem could be solved. The most efficient electrolyte uses an iodide-triiodide couple, but this not only absorbs and dissipates useful light but also corrodes silver electrical contacts. Now, the inventor of this type of PV cell, Michael Graetzel of the Swiss Federal Institute of Technology in Lausanne, has developed a novel electrolyte using a disulfide-thiolate redox couple that gives a power conversion efficiency of 6.4%, and does not lead to terminal corrosion.
Terminal improvement for solar cells