Luminescent down-shifting glasses for solar applications obtained by ion exchange

To verify the possibility of realizing down-shifting phenomena inside photovoltaic cover glass panels, silicate glasses where doped by ion exchange process. Different salt mixtures were compared. The effectiveness of the improvement of the power produced by a photovoltaic panel covered by the doped glasses was also tested by a home-made system acting as a solar simulator. The trends obtained from the characterization have been interpreted on the basis of changes on the optical basicity degree along the exchanged layers. A preliminary study is proposed about the relation between the optical basicity degree of the glass and the chemical state of the doping elements.