Building perovskite superlattices by shape-tuning perovskite nanocrystals for enhanced superfluorescent emission

Lead halide perovskite nanocrystals exhibit high emission coefficients with controllable shapes, sizes and compositions.

Moreover, the self-assembly of perovskite nanocrystals into consistent superlattices can generate a focused and intense burst of collective coupling emission called superfluorescence. These prominent features made them attractive in light-emitting and laser applications.

In SPUREPER, shape-tuning perovskite nanocrystals will be synthesised via a new route and pure perovskite superlattices through different shapes of nanocrystals with controllable aggregated structures and enhanced collective emission will be explored.

In WP1, a concept of post-injection of halide source and alkylamine ligands into the lead-oleate and caesium-oleate complexes is proposed to achieve monodisperse perovskite nanospheres and nanocubes.

Introducing other metal cations partially replacing lead at the beginning of synthesis controls the growth of crystals, and post-injecting alkylamine modifies the nanocrystals into a spherical shape.

In WP2, pure perovskite superlattices in various three-dimensional structures will be built by co-assembling perovskite nanospheres and nanocubes.

The size and relative ratios of nanospheres and nanocubes will be tuned to modify nanocrystal packing structure, packing density, and aggregated orientations in superlattices. Moreover, the self-assembling behaviour of solely perovskite nanospheres will be exploited.

In addition, the influence of the solvent, whose polarity and volatility are essential in forming a well-organised three-dimensional structure, on the arrangement behaviour of superlattices will be studied. In WP3, superfluorescence will be measured in these various perovskite superlattices.

Peak shift and intensity adjustment of the coupling emission will be correlated to the packing manners involving structure, density, and coupling number in the superlattices.