Near ultraviolet and visible-to-near-infrared spectral converting properties and energy transfer mechanism of Sr_2SiO_4:Ce^3+, Pr^3+ phosphor

A visible-to-near-infrared spectral converting phosphor Ce3+, Pr3+ co-doped Sr2SiO4 was synthesized by a solid-state reaction, and was developed as a potential solar spectral convertor for Si solar cells. The diffuse reflection, photoluminescence excitation and emission spectra at room temperature and at 3K were investigated. The visible and near infrared luminescent properties and energy levels of Pr3+ were investigated in detail. These results demonstrate that the absorption of Pr3+ was greatly broaden and enhanced in UV-Vis through efficient energy feeding by allowed 4f-5d absorption of Ce3+. The energy transfer mechanism including downshift and quantum cutting process is also proposed.