Dry Mechanochemical Synthesis of Highly Luminescent, Blue and Green Hybrid Perovskite Solids

A simple method to obtain bright photoluminescent wide bandgap mixed-halide 3D perovskites is reported. The materials are prepared by dry mechanochemical synthesis (ball-milling) starting from neat binary precursors, and show enhanced photoluminescence upon the addition of an adamantane derivative in the precursors' mixture. The structural characterization suggests that the additive does not participate in the crystal structure of the perovskite, which remains unvaried even with high loading of amantadine hydrochloride. By simple stoichiometric control of the halide precursors, the photoluminescence can be finely tuned from the UV to the green part of the visible spectrum. Photoluminescence quantum yields as high as 29% and 5% have been obtained for green- and blue-emitting perovskite solids, even at very low excitation densities.