Luminescent Solar Concentrators Based on Lanthanide Bimetallic Red-Emitting Metal–Organic Framework

Luminescent solar concentrators (LSCs) are large-area, high-efficiency solar energy-harvesting devices with considerable potential in building-integrated photovoltaics. Their performance is dominantly governed by the luminescent materials, which determine the light-harvesting efficiency, spectral conversion capability, and long-term operational stability of the devices. As important luminescent materials, metal–organic frameworks (MOFs) have advantages for LSC applications, including high luminescent efficiency, excellent stability, low environmental impact, and facile synthesis. Nevertheless, despite these favorable characteristics, the exploration of MOF-based luminescent materials in LSC devices remains relatively limited. In this work, a red-emitting MOF, designated as SCU-UEu-2, was synthesized with high reaction yield and good feasibility for large-scale production. Compared with Eu-based MOFs, SCU-UEu-2 shows a broader excitation range, while in contrast to quantum dots, it exhibits a narrower emission bandwidth. Moreover, the minimal spectral overlap between its absorption and emission effectively suppresses reabsorption energy losses, thereby improving LSC efficiency. The photoluminescent quantum yield (PLQY) of the SCU-UEu-2 reaches 90.28%. As a proof of concept, an LSC device incorporating SCU-UEu-2 was fabricated and systematically evaluated. Under simulated sunlight illumination (100 mW·cm –2 ), the device achieved a maximum optical conversion efficiency (η opt ) of 9.9%, demonstrating strong potential of MOF-based luminescent materials for high-performance LSC applications.