Solarization-induced redox reactions in doubly Ce3+/Mn2+-doped highly transmission glasses studied by optical absorption and photoluminescence

This work investigates the photoluminescence properties of high transmission glass (HTG) doped with CeO2 and MnO as well as their capability to transform the solar spectrum by absorption/emission via energy transfer from Ce3+ to Mn2+ into a more efficient red-enhanced spectrum for traditional Si-based solar cells. We show that Mn3+ and Mn2+ centers are formed in HTG, their relative concentration depending on the heat treatment and the presence of other dopants like Ce3+. Co-doping with CeO2 aims to stabilize Mn2+ by avoiding Mn3+ formation. We investigate the possibility of energy transfer from UV-absorbing Ce3+ to Mn2+ as a way of enhancing the HTG capability for blue-UV to red light transformation. The solarization effect through the Mn2+/Mn3+ ratio is also investigated for different CeO2 concentrations by means of optical transmittance and emission/excitation spectroscopy. Following these results, we perform an analysis of the optically enriched HTG for photovoltaic applications.