Abstract
Luminescent solar concentrators (LSCs) enable large-area collection of sunlight relevant to building-integrated photovoltaics. Reduced-dimensional metal halide perovskite nanoplatelets (PNPLs) have recently emerged as candidates for low-loss large-area LSCs due to the optoelectronic properties of perovskites combined with the large Stokes shift attainable using the multiple quantum well (MQW) structure. LSCs using bromine-based PNPLs have been demonstrated; however, the band gaps of bromine-based perovskites limit the absorption range. Iodine-based PNPLs allow broader absorption, but emission can be achieved only if the chemistry of PbIx2−x precursor complexes is engineered to provide the appropriate MQW distribution. Here, by controlling the polarity and Lewis basicity of the precursor solution, we modify the solvent-Pb2+ coordination and synthesize PNPLs having a uniform MQW distribution. This improves energy funneling, enabling a film PLQY (photoluminescence quantum yield) of 56% and 10 × 10 cm LSCs with an optical conversion efficiency of 2.0%, a 1.3-fold enhancement compared to the best previously reported room-temperature-fabricated perovskite LSCs.
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•Solvent-Pb2+ coordination engineering enables tailoring of the MQW distribution•56% PLQY for PNPL-PMMA films•2.0% optical conversion efficiency for 10 × 10 cm PNPL-based LSCs
Luminescent solar concentrators (LSCs) concentrate sunlight incident from a large area to a smaller one, thereby reducing photovoltaic (PV) materials consumption and enabling building-integrated PV. Reduced-dimensional metal halide perovskite nanoplatelets (PNPLs) have recently emerged as candidates for low-loss large-area LSCs, since they combine the optoelectronic properties of perovskite materials with reduced absorption-luminescence spectral overlap. Prior LSC studies based on PNPLs used bromine-based perovskites, and their absorption spectral range was limited to wavelengths shorter than 520 nm. We engineered the precursor chemistry of iodine-based perovskites to realize a room-temperature synthesis of PNPLs that exhibit a substantially uniform distribution of quantum wells. The high photoluminescence quantum yield led to an optical conversion efficiency that is 1.3× higher than in the best previously reported room-temperature-fabricated perovskite LSCs.
By judiciously engineering solvent and anti-solvent ratios during the preparation of precursors, Li et al. exploit solvent-Pb2+ coordination to control the multiple quantum well (MQW) distribution in perovskite nanoplatelets (PNPLs). They report 10 × 10 cm luminescent solar concentrator (LSC) devices based on PNPL/poly(methyl methacrylate) composites; these reach an optical conversion efficiency of 2.0%.