Efficient near-infrared quantum cutting in Ce~(3+) -Yb~(3+) codoped glass for solar photovoltaic

摘要

We report that Ce~(3+) can be an efficient sensitizer for Yb~(3+) and a broadband absorber for blue solar spectra. The broadband excitation for near-infrared (NIR) emission is ranged from 350 nm to 500 nm. The allowed 4f→5d transition and the adjustable lowest 5d level make the energy transfer from Ce~(3+) to Yb~(3+) efficiently. Therefore the quantum efficiency (QE) is also very high up to 154.3%. Furthermore, the energy of Yb~(3+2)F_(7/2)→~2F_(5/2) transition matches well with the band gap of a single-junction Si. Given the broad excitation band, high absorption coefficient and excellent mechanical, thermal, and chemical stability, this system can be used as down-conversion (DC) layer for solar cells.