CsPbBr3 Superstructures with Circularly Polarized Photolumines‐Cence Obtained by the Self‐Assembly and Annealing of Nanoclusters

Abstract We report a two‐step approach to fabricate CsPbBr 3 superstructures with strongly circularly polarized photoluminescence by self‐assembly of nanoclusters on a substrate, followed by their annealing. In the first step, the nanoclusters self‐assemble upon solvent evaporation, a process that forms mesoscopic superstructures whose geometrical arrangement at the μm‐scale confers them optical chirality. In the second step, mild annealing of such superstructures induces the coalescence of the nanoclusters, accompanied by a continuous red shift of the photoluminescence up to 530 nm, with preservation of the μm‐scale wires bundles and the chiral properties of the sample (g lum =0.1). The successful chirality transfer from the initial nanoclusters assemblies to these final CsPbBr 3 superstructures provides a convenient way to obtain circularly polarized emitters.