Nanocrystal superlattices (NC SLs) have long been sought as promising metamaterials, with nanoscale-engineered properties arising from collective and synergistic effects among the constituent building blocks. Lead halide perovskite (LHP) NCs come across as outstanding candidates for SL design, as they demonstrate collective light emission, known as superfluorescence, in single- and multicomponent SLs. Thus far, LHP NCs have only been assembled in single-component SLs or coassembled with dielectric NC building blocks acting solely as spacers between luminescent NCs.
View Article and Find Full Text PDFStrong coupling of a confined optical field to the excitonic or vibronic transitions of a molecular material results in the formation of new hybrid states called polaritons. Such effects have been extensively studied in Fabry-Pèrot microcavity structures where an organic material is placed between two highly reflective mirrors. Recently, theoretical and experimental evidence has suggested that strong coupling can be used to modify chemical reactivity as well as molecular photophysical functionalities.
View Article and Find Full Text PDFLead halide perovskite nanocrystals (NCs) are highly suitable active media for solution-processed lasers in the visible spectrum, owing to the wide tunability of their emission from blue to red via facile ion-exchange reactions. Their outstanding optical gain properties and the suppressed nonradiative recombination losses stem from their defect-tolerant nature. In this work, we demonstrate flexible waveguides combining the transparent, bioplastic, polymer cellulose acetate with green CsPbBr or red-emitting CsPb(Br,I) NCs in simple solution-processed architectures based on polymer-NC multilayers deposited on polymer micro-slabs.
View Article and Find Full Text PDFNanocrystal (NC) self-assembly is a versatile platform for materials engineering at the mesoscale. The NC shape anisotropy leads to structures not observed with spherical NCs. This work presents a broad structural diversity in multicomponent, long-range ordered superlattices (SLs) comprising highly luminescent cubic CsPbBr NCs (and FAPbBr NCs) coassembled with the spherical, truncated cuboid, and disk-shaped NC building blocks.
View Article and Find Full Text PDFThe 1:1:1 reaction of DyCl·6HO, K[Co(CN)] and bpyO in HO has provided access to a complex with formula [DyCo(CN)(bpyO)(HO)]·4HO () in a very good yield, while [DyFe(CN)(bpyO) (HO)]·4HO () was also precipitated (also in a high yield) using K[Fe(CN)] instead of K[Co(CN)]. Their structures have been determined by single-crystal X-ray crystallography and characterized based on elemental analyses and IR spectra. Combined direct current (dc) and alternating current (ac) magnetic susceptibility revealed slow magnetic relaxation upon application of a dc field.
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