Broadband downshifting luminescence of Cr3+/Yb3+-codoped fluorosilicate glass

Cr3+/Yb3+-codoped glasses were studied as broadband down shifting materials for improving solar cells’ efficiency. We observed Föster resonance energy transfers (FRET) from Cr3+: 4T2g to Yb3+: 2 F5/2. The ET efficiency was up to 84 %, and the measured quantum yield (QY) reached 21.51 %. The glass can convert solar photons in super wide UV–Vis range to near infrared photons with the minimum quantum yields larger than 10%. Thus, such materials can be applied for improving silicon solar cells’ conversion efficiency.

► The Cr3+/Yb3+-codoped glass has a broad UV–VIS excitation band.
► The glass can convert UV–VIS solar photons to solar-cell-utilizable NIR photons.
► Föster resonance energy transfers (FRET) exist between Cr3+: 4T2g and Yb3+: 2 F5/2.
► FRET efficiency is up to 84 % and the quantum yield reaches 21.51 %.