Development of ethylene-vinyl acetate copolymer/graphene oxide nanocomposites for crystalline silicon photovoltaic modules

Renewable sources of energy, such as solar cells, stand out as promising sustainable alternatives, given the growing world energy demand. The crystalline silicon photovoltaic (PV) modules are the most used in the conversion of solar energy into electricity. These modules are subject to weather conditions that may cause degradation of the ethylene vinyl acetate copolymer (EVA) encapsulant (cross-linked EVA copolymer), affecting the efficiency, stability and service life of the PV conversion. In this work, the development of an encapsulant was performed, based on the addition of graphene oxide (GO) to EVA encapsulant forming the nanocomposite (EVA/GO), in order to improve the stabilization against photodegradation. Nanocomposites with GO concentrations wt. %: 0.25%, 0.50%, 0.75%, 1.0% and 2.0% were characterized by: Fourier transform infrared spectroscopy by attenuated total reflectance (ATR-FTIR) thermogravimetry (TG), and differential scanning calorimetry (DSC), before and after they underwent accelerated aging processes in Weather-Ometer and UVB rays chambers. In general, the addition of GO minimized EVA encapsulant degradation. Only the encapsulant with GO concentration of 0.25 wt% was shown as promising for photovoltaic modules, since the transparency of the films with higher concentrations was impaired.