Solar Energy Materials and Solar Cells, Vol.176, 19-29, 2018
Graphene nanoplatelets as an anticorrosion additive for solar absorber coatings
Efficiently transforming solar energy into heat requires an understanding of spectrally selective coatings at the atomic, molecular, corrosive and spectrally selective levels. Here, experiments were conducted and analyzed to rationalize and ultimately understand the complex behaviours of spectrally selective coatings in corrosion environments. By exploring reactions that modify graphene nanoplatelets, the preparation of stable dispersions, the incorporation in sol-gel binder, and the preparation of spectrally selective coatings, we demonstrated that (i) a successful graphene nanoplatelet modification is important for their incorporation into binders as sol-gels, (ii) the modified products do not influence the optical properties of the coatings, (iii) incorporating nanoplatelets drastically improves corrosion resistance, and (iv) thinner coatings can be used to acheieve the same anticorrosion properties as other treatments. We believe this experimental insight provides a pathway for the rational design of stable spectrally selective paint coatings that are urgently needed for the development of a new generation of reliable and affordable absorber coatings for efficient solar energy harvesting.