Solid-state fluorescent carbon dots-based composite optical waveguide film enables transparent and high-performance luminescent solar concentrators

Aggregation-caused quenching (ACQ) is a great obstacle for carbon dots (CDs) to be applied in the photovoltaic fields. In this work, we report that acid-catalyzed hydrolytic condensation of N-[3-(trimethoxysilyl)propyl]ethylenediamine (KH-792) is utilized to generate organosilicon matrices, meanwhile, CDs are covalently linked to the organosilicon matrices to realize solid-state fluorescence via one-step solvothermal method. This approach enables CDs to be uniformly distributed in the organosilicon matrices to produce strong solid-state fluorescence. Most importantly, the obtained blue fluorescent CDs (b-CDs) can be combined with (3-Aminopropyl)triethoxysilane (APTES) to form a highly transparent optical waveguide film on the glass to construct high-performance luminescent solar concentrators (LSCs) with high loading amount. By changing the CDs loading amounts and volume of the coating solution, the transparent LSCs (5 × 5 × 0.2 cm3) with high optical conversion efficiency (ηopt) of 2.83% can be achieved. In addition, the b-CDs powder can be intergrated with 365 nm chips to successfully fabricate monochromatic light-emitting diodes (LEDs). The prepared b-CDs powder with strong solid-state fluorescence shows great potential in photoelectric devices.