![]() ![]() In this study, chiral methylammonium lead halide perovskite nanoplatelets (NPLs) with varied halide and ligand compositions are prepared using direct synthetic methods. « lessĬhiral perovskites have generated significant recent interest, yet little is known about how their chiro-optical properties arise. Using this approach, we achieve an optical quantum efficiency of 26% and an internal concentration factor of 3.3 for LSCs with an area of 10 × 10 cm 2, which represents a fourfold enhancement over the best previously reported perovskite LSCs. Efficient ultrafast non-radiative exciton routing within each more » PNPL (0.1 ps –1) produces a large Stokes shift and a high PLQY simultaneously. Here, we devised a facile synthetic route to obtain layered perovskite nanoplatelets (PNPLs) that possess a tunable number of layers within each platelet. Here we employ layered hybrid metal halide perovskites-ensembles of two-dimensional perovskite domains-to fabricate low-loss large-area LSCs that fulfil this requirement. Achieving a low-loss LSC requires reducing the reabsorption of emitted light within the absorbing medium while maintaining high photoluminescence quantum yield (PLQY). In luminescent solar concentrator (LSC) systems, broadband solar energy is absorbed, down-converted and waveguided to the panel edges where peripheral photovoltaic cells convert the concentrated light to electricity. It is also confirmed that the field-induced linear polarization is sensitive to the monoclinic exchange term, whereas the field-induced circular polarization is immune to such term. These findings are well explained by an effective mass model that includes exchange terms unique to the monoclinic symmetry as a perturbation of the EFS in the approximate tetragonal symmetry. Furthermore, it is found that the dark exciton has an anomalous field-induced circular polarization, which cannot be explained by the classical more » Boltzmann distribution of spin-polarized species. Under a high magnetic field in Faraday/Voigt configuration, large field-induced circular/linear polarization is observed in the PL band related to the dark exciton, which is magnetically activated. Three exciton bands are identified in the PL spectrum associated with bound, dark, and bright excitons, respectively. A comprehensive study of the exciton fine structure (EFS) is presented in 2D-phenethylammonium lead iodide films using magnetic field-induced polarization of photoluminescence (PL) in both Faraday and Voigt configurations at fields up to 25 Tesla. ![]()
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