Michael Gratzel, the inventor of organic solar cells and a professor at EPFL (Ecole Polytechnique Federale de Lausanne) in Switzerland is hitting headlines again with the latest achievement in the field of organic photovoltaics: an efficiency figure of 15 percent.
His new solid-state dye-sensitized solar cells (DSSC) are two percent more efficient than the last iteration, but this can mean a lot if the technology is mass-produced and commercialized on a large scale.
Gratzel used a perovskite structure (CH3NH3PbI3) as a dye sensitizer and a hole transport material consisting of organic materials acting as electrolyte. TechOn reports its DSSC as having the structure of glass/FTO/TiO2/CH3NH3PbI3/HTM/Au.
In 2009, a team of researchers from Toin University in Yokohama, Japan, proposed the same formula, but that only yielded a 3.8% efficiency. The secret lied in the particle diameter of the perovskite material, and the original inventor seems to have figured that out eventually.
Three years ago, Michael Gratzel received a price of more than $1 million as the Millennium Technology Prize for inventing DSSCs.