For the first time to our knowledge, a study about the increase in external quantum
efficiency (EQE) by down-shifters (DS) encapsulated by industrial procedures on
photovoltaic (PV) modules is presented. EQE improves substantially in the UV range not
only because of the optical path optimization for photons reaching the solar cell, but also
it is attributed to the substantial reduction of DS photons scattered out of the solar cell
when the outermost surface of the DS layer is embedded in ethyl-vinyl-acetate.
Consequently, a proper encapsulation of DS layers is required for the optimal
characterization of EQE. Moreover, the encapsulation of the DS layer substantially
reduces the degradation of its luminescent properties due to UV radiation. However, the
reduction of the EQE under UV radiation for the encapsulated DS layer is still high and
should be substantially reduced for the integration of down-shifting properties in the
lamination process of PV modules.
