Monodisperse Formamidinium Lead Bromide Nanocrystals with Bright and Stable Green Photoluminescence

Abstract

Bright green emitters with adjustable photoluminescence (PL) maxima in the range of 530–535 nm and full-width at half-maxima (fwhm) of <25 nm are particularly desirable for applications in television displays and related technologies. Toward this goal, we have developed a facile synthesis of highly monodisperse, cubic-shaped formamidinium lead bromide nanocrystals (FAPbBr3 NCs) with perovskite crystal structure, tunable PL in the range of 470–540 nm by adjusting the nanocrystal size (5–12 nm), high quantum yield (QY) of up to 85% and PL fwhm of <22 nm. High QYs are also retained in films of FAPbBr3 NCs. In addition, these films exhibit low thresholds of 14 ± 2 μJ cm–2 for amplified spontaneous emission.

High‐Efficiency Formamidinium Lead Bromide Perovskite Nanocrystal‐Based Light‐Emitting Diodes Fabricated via a Surface Defect Self‐Passivation Strategy

“…The crystal structures of as‐prepared perovskite NCs are analyzed by X‐ray diffraction (XRD) patterns (Figure S6a, Supporting Information). The main diffraction peaks correspond to the cubic phase of FAPbBr 3 with the Pm‐3m space group, as reported in previous studies . The peaks in the XRD patterns remained, which indicates that the additional FABr has a negligible effect on the crystal structure of perovskite NCs.…”

Quantifying the Thermodynamics of Ligand Binding to CsPbBr3 Quantum Dots

“…An up-and-coming class of QDs is the colloidal lead halide perovskites (APbX 3 , where A = CH 3 NH 3 + , CH(NH 2 ) 2 + , Cs + ; X = Cl − , Br − , I − ) because of their excellent optoelectronic properties, such as bright photoluminescence (PL) with narrow spectral line widths that cover a wide color gamut. [2–4] These properties have made lead halide perovskite QDs intriguing for use in a multitude of optical devices, such as LEDs [5–7] and solar cells. [3,8] Unlike the more traditional II-VI QDs, lead halide perovskite QDs are much more ionic in their bonding, including bonding with ligands.…”

Metal halide perovskite nanocrystals and their applications in optoelectronic devices

“…This hot injection method has been widely used in the synthesis of colloidal NCs with various compositions and morphologies. Loredana and coworkers synthesized FAPbBr 3 and CsPbBr 3‐ x I x colloidal QDs with PL QY over 85% and FWHM of <22 nm …”

“…Kovalenko's group let Pb(acetate) 2 and FA‐acetate react with OA in ODE and injected oleylammonium bromide (OAmBr) at 130°C to synthesize FAPbBr 3 QDs. The luminescence wavelength of synthesized QDs can be adjusted from 470 to 535 nm by changing the reaction temperature or the amount of OAmBr . Manna's group synthesized all‐inorganic and organic‐inorganic hybrid perovskite NCs by hot injection with benzoyl halides as halogen precursor.…”