Enhanced solar photons harvesting of a-SiC:H solar cells with ZBLA fluoride glasses containing rare earth ions

As encapsulation glasses for a-SiC:H cells, Yb3+/Ce3+-Er3+ tri-doped ZBLA fluoride glasses were prepared using the high temperature melt-quenching method and the optical characteristic of the glass were measured. Depending on the nature of rare earth doped ZBLA fluoride glasses, both near infrared (low-energy) and ultraviolet (high-energy) solar photons can be transformed into visible photons. By downshifting the ultraviolet (280-350 nm) light combined with upconverting the near infrared (900-1100 nm) light, the glass can emit strong visible (500-700 nm) light, which matches well with the spectral responsivity of a-SiC:H cells. The conversion of non-absorption photons energies by upconversion and downshifting leads to promote the improvement of a-SiC:H cells performances, and measurement shows relatively increase of 7.6%-0.8% in cell efficiencies.