High‐Efficiency Luminescent Solar Concentrators Based on Antifogging and Frost‐Resisting Fluorescent Polymers: Adding Multiple Functions for Sustained Performance

Abstract

Luminescent solar concentrators (LSCs) are light‐management devices able to harvest and downshift sunlight, making it available to edge‐coupled photovoltaic cells for light‐to‐electricity conversion. When operating in real‐life outdoor scenarios, LSCs can be exposed to humid/freezing environments which may yield fogging and frosting, ultimately resulting in detrimental performance decay owing to reduced photon absorption and photon trapping efficiency within the waveguide. To address this issue, the first demonstration of an antifogging/frost‐resisting highly efficient thin‐film LSC is presented in this work, based on a tailored semi‐interpenetrating polymer network serving as the host matrix material, where the antifogging behavior is imparted by the simultaneous presence of hydrophilic and hydrophobic segments in the macromolecular structure, whereas the fluorescent response is achieved via the incorporation of a coumarin‐functionalized methacrylic monomer. By judicious selection and compositional tuning of an additional luminescent guest dopant with excellent spectral match with the fluorescent host matrix, highly efficient (≈98%) energy transfer is achieved. Optimized LSC devices exhibit external and internal photon efficiencies as high as 3.96% and 34.79%, respectively. In addition, persistent and reproducible antifogging/frost‐resisting functionality is demonstrated during aggressive aging tests under UV‐light, with preserved fluorescence emission and prolonged and sustained device efficiency.

Integration of Conjugated Copolymers‐Based Luminescent Solar Concentrators with Excellent Color Rendering and Organic Photovoltaics for Efficiently Converting Light to Electricity

“…To study the light concentrating ability of the concentrators, the η opt of the LSCs were measured according to the method proposed by Griffini et al [49,50] Encouragingly, the η opt values of the PPF-IF, PPF-NIF, and PPF-F based LSCs were determined to be 5.71 ± 0.08%, 9.12 ± 0.13%, and 12.08 ± 0.06%, respectively. Subsequently, an LSC-solar cell system was fabricated to evaluate its photon-to-electron conversion capability, which is shown in Figure 3a.…”

“…49, and the values for the light passing through PPF-IF, PPF-NIF, and PPF-F based LSCs are still as high as 95.74, 92.71, and 93.24, respectively. To experimentally verify that these LSCs have good color rendering ability, they were utilized as filters to take pictures of different color-dominated scenes, as shown in Figure4d.…”

Semi‐Transparent Luminescent Solar Concentrators Based on Intramolecular Energy Transfer in Polyurethane Matrices

“…Some recent examples of this type include small-molecule or 𝜋-conjugated-polymer pairs, [18][19][20] aggregation-induced-emission luminophores, [21][22][23] dendrimeric structures [24,25] and nanoparticle-based hybrid systems, [26,27] in some cases in the presence of a photoactive host matrix taking part in the FRET process. [28][29][30] In this device configuration, a key role is played by the photophysical characteristics of the luminophores and by their concentration in the host matrix, the latter influencing their average intermolecular distance, identified by the so-called critical FRET radius R 0 , which should be in the 2-6 nm range for optimal interaction. [17,31] Alternative strategies for FRET-based LSC systems have targeted the covalent incorporation of one or more luminophores within the macromolecular structure of the host matrix.…”