Luminescent solar concentrators (LSCs) represent an interesting solution for light harvesting, management and conversion, efficiently operating under both direct and diffuse light conditions. In such devices, incident photons are absorbed and re-emitted by luminophore species embedded in a waveguide, and transported by total internal reflection towards solar cells for the light-to-electricity conversion. Conventional luminophores often exhibit diminished photoluminescence in concentrated solutions or at the solid state, negatively affecting the final performance of the devices.
To overcome these limitations, the present work investigates the enhanced emission properties associated with aggregation-induced emission (AIE) emitters. Specifically, newly synthesized macromolecules were employed as photonically active species through copolymerization between methyl methacrylate and a tetraphenyl ethylene based AIE-active monomer at varying molar concentrations. Two distinct radical polymerization methods were evaluated and explored: free radical polymerization (FRP) and reversible addition-fragmentation chain transfer (RAFT) polymerization.
The resulting copolymers were comprehensively characterized in terms of their molecular, thermal, and optical properties, demonstrating the superiority of the RAFT method. This technique provided narrower molecular weight distribution (Đ~1.2) and yielded copolymers with more consistent glass transition temperatures, absorption features, and photoluminescence quantum yields. Subsequently, LSCs were fabricated by deposition of thin polymeric films onto optical glass substrates and their optical and photovoltaic characteristics were assessed under simulated sunlight conditions, with LSCs deriving from RAFT polymerization demonstrating improved performance.
This study illustrates a promising approach for enhancing the efficiency of LSCs through the manipulation of macromolecular architecture and the strategic incorporation of AIE-active species within polymer matrices.