Mn Doping in Centimeter-Sized Layered 2D Butylammonium Lead Bromide (BA₂PbBr₄) Single Crystals and Their Optical Properties

Abstract

Layered lead halide perovskites such as butylammonium lead bromide (BA2PbBr4) possess a multiple-quantum-well structure, which is expected to enhance the interaction between the excitons and Mn dopants. Therefore, doping Mn in large single crystals of layered perovskites may induce interesting magneto-optic and magneto-electric properties, with minimal contributions from the detrimental grain boundary effects. Furthermore, these single crystals show stark differences in excitonic absorption and emission (dual emission) compared with the measurements done on the ensemble of corresponding microcrystals. Therefore, exploring the exciton–Mn interactions by performing measurements on one large crystal is important. We report the one-pot synthesis of centimeter-sized Mn-doped BA2PbBr4 single crystals to study the exciton–Mn interaction measured on a single crystal. Mn-doped BA2PbBr4 single crystal shows dual excitonic emission, and both of the excitonic features transfer their energies nonradiatively to Mn dopants, yielding Mn d–d emission with quantum yield ∼26%. The Mn emission, in these single crystals, shows a strong excitation energy dependence, which is related to the penetration depth of the excitation light into the single crystals. We also exfoliate the BA2PbBr4 single crystals using a Scotch-tape method. The differences in the optical properties of the exfoliated sample and the single crystal provide insights into both Mn doping and exciton–Mn interactions.

Doped Lead Halide White Phosphors for Very High Efficiency and Ultra‐High Color Rendering

“…[39] However,f or low concentrations of Mn dopants,t he influence of Mn on the structure is negligible and cannot be observed by X-ray diffraction. [40] To confirm the absence of amorphous phases, solid-state NMR was carried out. No differences are observed for the samples without or with Mn doping (Supporting Information, Figure S3), showing that such doping does not influence the environments of lead and organic molecules.…”

Mn2+‐Doped Metal Halide Perovskites: Structure, Photoluminescence, and Application

“…Nag's group reported the centimeter‐sized layered single crystals of Mn 2+ ‐doped BA 2 PbBr 4 with dual excitonic emissions. [ 173 ] As shown in Figure a,b, the emission signal is collected by placing a detector in the same front side of the sample, and the single crystal shows the single excitonic emissions. When the emission signal is detected from the back side of the single crystal, the dual excitonic emissions are observed.…”

Dual Emission of Water‐Stable 2D Organic–Inorganic Halide Perovskites with Mn(II) Dopant

“…Subsequently, high PL‐QYs of thermostability‐enhanced all‐inorganic CsPbX 3 materials were reported in succession . Further exploration of Mn 2+ ‐doped perovskite has also been extended to OIHPs . However, there is no report on water‐stable Mn‐doped perovskite nanocrystals.…”