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Luminescent solar concentrators (LSCs) are considered promising in their application as building-integrated photovoltaics (BIPVs). However, they suffer from low performance, especially in large-area devices. One of the key issues is the self-absorption of the luminophores. In this report, we focus on the study of self-absorption in perovskite-based LSCs. Perovskite nanocrystals (NCs) are emerging luminophores for LSCs. Studying the self-absorption of perovskite NCs is beneficial to understanding fundamental photon transport properties in perovskite-based LSCs. We analyzed and quantified self-absorption properties of perovskite NCs in an LSC with the dimensions of 6 in × 6 in × 1/4 in (152.4 mm × 152.4 mm × 6.35 mm) using three approaches (i.e., limited illumination, laser excitation, and regional measurements). The results showed that a significant number of self-absorption events occurred within a distance of 2 in (50.8 mm), and the photo surface escape due to the repeated self-absorption was the dominant energy loss mechanism.

Luminescent solar concentrators (LSCs) have been widely studied for their potential application as building-integrated photovoltaics (BIPV). While numerous efforts have been made to improve the performance, the photothermal (PT) properties of LSCs are rarely investigated. In this report, we studied the PT properties of an LSC with a power conversion efficiency (PCE) of 3.27% and a concentration ratio of 1.42. The results showed that the total PT power of the LSC was 13.2 W, and the heat was concentrated on the edge of the luminescent waveguide with a high heat power density of over 200 W m−2.

Luminescent solar concentrators (LSCs) are considered promising photovoltaic (PV) devices to circumvent practical issues of applying conventional solar panels to the built environment. However, LSCs suffer from low power conversion efficiencies (PCEs) (typically 2), despite numerous efforts having been made to develop novel luminescent materials and optical techniques. In this report, we proposed to utilize photothermal (PT) energy of the LSCs to further improve the PCE. We conducted a preliminary investigation on the PV and PT properties of an LSC with dimensions of 300 mm × 300 mm × 5 mm. The results showed that the PT power (27.05 W) was much higher than the PV power (2.12 W). Further analysis indicated that the PCE could reach 3.41% for a device of 1 m2.

In this study, a polymer dispersed cholesteric liquid crystal (PDChLC) film obtained via a one-step fabrication technique based on photopolymerization of a thiol-acrylate reaction system was prepared and characterized for the first time. The effects of the chiral dopant, the influence of thiol monomer functionality and content on the morphology and subsequent performance of the PDChLC films were systematically investigated. It was demonstrated that the addition of a small amount of chiral dopant slightly increased the driving voltage, but decreased the off-state transmittance significantly. Furthermore, scanning electron micrographs (SEM) shown that the liquid crystal (LC) droplet size decreased at first and then increased with the increasing amount of thiol monomer functionality, while increasing the thiol content increased the LC droplet size. Correspondingly, the electro-optical switching behavior was directly dependent on LC droplet size. By tuning the raw material composition, PDChLC film with optimized electro-optical performance was prepared.

Polymer-dispersed liquid crystal (PDLC) films were prepared by the ultraviolet-light-induced polymerization of photopolymerizable monomers in nematic liquid crystal/chiral dopant/thiol-acrylate reaction monomer composites. The effects of the chiral dopant and crosslinking agents on the electro-optical properties of the PDLC films were systematically investigate. While added the chiral dopant S811 into the PDLC films, the initial off-state transmittance of the films was decreased. It was found that the weight ratio among acrylate monomers, thiol monomer PETMP and the polymercaptan Capcure 3-800 showed great influence on the properties of the fabricated PDLC films because of the existence of competition between thiol-acrylate reaction and acrylate monomer polymerization reaction. While adding polymercaptans curing agent Capcure 3-800 with appropriate concentration into the PDLC system, lower driven voltage and higher contrast ratio were achieved. This made the polymer network and electro-optical properties of the PDLC films easily tunable by the introduction of the thiol monomers.