Óxido de grafeno (GO) funcionalizado adicionado ao encapsulante EVA para aplicação em módulos fotovoltaicos de silício cristalino

Abstract

In order to be economically viable, photovoltaic modules must have durability of at least 25 years of operation. In order to increase the useful life of the modules, it is necessary to control the degradation of the encapsulant, the ethylene vinyl acetate copolymer (EVA), by the action of ultraviolet radiation (UV) and other elements of weathering. This article aims to evaluate the applicability of nanocomposites of EVA and graphene oxide (GO) functionalized with octadecylamine (ODA) as encapsulants, characterizing them, before and after the aging processes, by using the analytical techniques: spectroscopy in infrared region by Fourier transform (ATR-FTIR), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). In order to acquire a better dispersion of GO in the polymeric matrix of the EVA encapsulant, we opted for its functionalization with octadecylamine. The prepared nanocomposites were aged in a UVB chamber, which is usually the most aggressive radiation for polymers. The results of the ATR-FTIR analysis indicated that the presence of GO increased the degradation resistance. An improvement in the thermal properties of unaged films was also observed, which was not observed in the aged ones. It is concluded that the addition of GO brought benefits regarding the resistance to material degradation, although its use in nanocomposites for photovoltaic cell encapsulants depends on the control of the number of graphene sheets, which will modulate the optical properties and the transparency of the encapsulant. The article presents a contribution to the advancement of research regarding the degradation, by UVB radiation, of the EVA encapsulant present in crystalline silicon photovoltaic modules.