Abstract: At present, the environmental problems caused by fossil fuels are becoming more prominent, and it is imperative to reduce carbon emissions. Based on this situation, the solar photovoltaic technology has become the fastest growing renewable energy technology, and it has great promise to solve current resource and environmental problems. Owing to the characteristics of adjustable structure, sustainable use, and low cost, the luminescent solar concentrators are attracting more and more attention from among photovoltaic field. The typical luminescent solar concentrator is composed of two parts, including the light waveguide coated or embedded with the emitting fluorophores, a photovoltaic cell mounted on the light waveguide edge. Carbon dots have attracted increasing attention in the field of luminescent solar concentrators due to their environmental friendliness, economic applicability, simple synthesis methods, and excellent optical properties. However, when carbon dots are compatible with hydrophilic polymer waveguide materials as luminescent substrates, the poor compatibility of most carbon dots in polymers and the brittleness of hydrophilic polymers severely limit the practical application of luminescent solar concentrators. In order to solve these problems, the synthesis of a carbon dot doped with other elements or new carbon dot structure has become the focus of attention. In addition, the suitable host matrix needs to be explored, such as organic-inorganic hybrid matrix, multifunctional matrix, polysiloxane matrix, etc. In this work, a bright yellow emitting silicon coated carbon dot with a Stokes shift of 150 nm, a quantum yield of 10.94%, and good dispersibility and compatibility was synthesized using the hydrolysis condensation of 3-aminopropyltriethoxysilane, along with phthalic acid and o-phenylenediamine. At the same time, a series of 3 cm×3 cm×0.1 cm sizes were prepared by combining dimethyl siloxane with good compatibility and high flexibility as the waveguide material, flexible luminescent solar concentrators based on silicon coated carbon dots with different mass percentages, among which the best performing solar concentrator has an energy conversion efficiency of 1.05%. This work combines the advantages of silicon coated carbon dots with polydimethylsiloxane, which has potential value for the practical application of luminescent solar concentrators.

Key words: silicon coated carbon dot, luminescent solar concentrator, compatibility, flexibility, 3-aminopropyltriethoxysilane, polydimethylsiloxane