Degradation analysis of highly UV-resistant down-shifting layers for silicon-based PV module applications

In this work, the external quantum efficiency (EQE) of [Eu(bta)3me-phen] downshifters (DS) encapsulated by industrial procedures on photovoltaic (PV) modules is presented. The samples have been laminated using the DS layers faced-up and faced-down. The results obtained for the DS layers present an EQE enhancement of 1.2 % for the faced-up samples and 0.8 % for the faced-down samples. A climate chamber was used to evaluate the EQE performance during the ageing process; a temperature of 22 degrees C and relative humidity of 30 % was fixed. Several time cycles have been used to achieve a total UV dose of 454.94 kWh. After a 136.51 kWh dose, the increment of the EQE for the faced-up samples vanishes. In contrast, after a dose of 454.94 kWh, the EQE enhancement for samples with the DS layer faced down remains unaltered.