Large-Area Semi-Transparent Luminescent Solar Concentrators Based on Large Stokes Shift Aggregation-Induced Fluorinated Emitters Obtained Through a Sustainable Synthetic Approach

In this study, the design, fabrication, and characterization of semi-transparent large-area luminescent solar concentrators (LSCs) in thin-film configuration is reported, incorporating a novel organic luminophore (PFPBNT) emitter based on a π-conjugated core flanked by two naphthothiophene units obtained through a chemically sustainable synthetic approach. As found experimentally and validated through computational modeling, PFPBNT exhibits aggregation-induced emission (AIE) behavior, broad absorption in the UV–vis spectrum and significant Stokes shift (≈4632 cm–1), thereby making it an excellent candidate as luminophore in thin-film LSCs based on a poly(methyl methacrylate) (PMMA) matrix, where it is found to show good compatibility, homogeneous distribution, and excellent photostability. After extensive device optimization, PFPBNT/PMMA LSCs with suitable luminophore concentration (12.5 wt%) showed an internal photon efficiency of 17.3% at a geometrical gain of 6.25 under solar-simulated illumination. The size scalability of these systems was also evaluated by means of ray-tracing simulations on devices of up to 1 m2 surface area. This work demonstrates semi-transparent large-area thin-film LSCs incorporating chemically sustainable AIEgen luminophores, thus opening the way to the development of synthetically affordable, efficient, and stable emitters for the photovoltaic field.