Waterborne advanced optical coatings based on polymer composite with hybrid graphene-metal phthalocyanine nanofiller

This study focuses on the development of waterborne coatings, based on polymer composites with incorporated hybrid filler composed of reduced graphene oxide (rGO) and metal phthalocyanines (MPc) with potential applications in the field of optics. The resulting composite coatings exhibit electrical conductivity on the order of 10 −5 S/m which places these composites in the group of semiconductors. Two distinct morphologies were achieved. The first features homogeneously distributed nanoaggregates of the hybrid filler within the polymer matrix, while the second involves the formation of a continuous network of the filler, facilitated by the particulate nature of the polymer particles in aqueous dispersions. All composites demonstrated enhanced optical properties, including increased UV/visible light absorption, decreased band gap and reduced energies for both direct and indirect allowed transitions. These observations suggest the formation of intermediate energy levels within the band gap, which facilitate electron transitions from the valence band to the conduction band. Moreover, the dielectric properties of the composites were significantly improved, as evidenced by increased dielectric constants and dielectric loss. The enhanced optical properties can be attributed to the abundant three-phase interface between rGO, MPcs, and the polymer, the good compatibility among the phases within the composites, and the semiconductive properties. Overall, these findings underline the potential of rGO/MPc-based composites as versatile materials for advanced technological applications in the optics and electronics industries. • Hybrids of reduced graphene oxide-rGO and metal phthalocyanines- MPc were prepared • rGO/MPc hybrids were introduced in methacrylic waterborne optical polymer coatings • Enhanced optical properties are due to abundant three-phase rGO/MPc/polymer interface • Dielectric properties of the composites were significantly improved • rGO/MPc/polymer composites present potential for advanced optical applications