Highly transparent all-perovskite luminescent solar concentrator/photovoltaic windows

Abstract

Luminescent solar concentrators (LSCs) play a major role as light suppliers at the boundaries between indoor and outdoor spaces in buildings. The performances of solar panels coupled with LSCs are directly influenced by the photoluminescence (PL) characteristics of fluorophores, among which inorganic perovskite nanocrystals (PeNCs) have shown great potential. A large Stokes shift in these NCs spanning the ultraviolet (UV), visible, and near-infrared regions can be achieved through metal doping, leading to significant improvements in the PL quantum yields and reduced PL reabsorption. However, practical approaches for coupling perovskite LSCs (PeLSCs) with perovskite solar cells (PSCs) are lacking. The design of all-perovskite LSC/photovoltaic (PV) windows is essential to prepare perovskite-based building-integrated PV systems. Thus, Mn-doped CsPbCl₃ NCs were employed as PL-reabsorption-free fluorophores for LSCs. Their significant Stokes shift allowed for efficient PL propagation to the LSC edges. The Mn:CsPbCl₃/polystyrene composite films used in the LSCs demonstrated excellent optical transparencies and low haze values. When coupled with 16 series-connected high-efficiency PSCs, the PeLSC/PV windows exhibited impressive optical (5.38%) and power conversion (0.43%) efficiencies at a large geometric factor of 25 under 1 sun illumination. Using PeLSC/PV windows as self-powered UV light detectors, an excellent responsivity, specific detectivity, and noise equivalent power were obtained due to strong PL emission from the LSCs, even under weak UV light. An excellent power conversion efficiency was retained (86.3%) after 1000 h of operation due to protection of the solar absorbers from UV light by the long-wavelength PL emission of the LSCs.