Synthesis, Structure, and Photoelectric Properties of a Novel 0-Dimensional Organic–Inorganic Hybrid Perovskite (2-5-py)₂MnBr₄

Abstract

In this study, a new type of 0-dimensional organic–inorganic hybrid perovskite single crystal (2-5-py)2MnBr4 was synthesized using 2-amino-5-methylpyridine (2-5-py) as the organic ligand. The crystal is a center-symmetric P-1 space group with a grain size of 20 mm, which belongs to the triclinic crystal system. It has a strong absorption of violet and blue light as well as excellent thermal stability. Its optical band gap is 2.38 eV, which is in good agreement with the theoretical band gap (2.39 eV) calculated by density functional theory. Under the excitation of a suitable light source, it can emit 526 nm pure bright green lights, which are confirmed by the main peaks to be almost in the green range with a full width at half maximum of 45 nm. As a result, the quantum efficiency and fluorescence lifetime reached a high level of 44.2% and 117 μs, respectively. Based on the good fluorescence performance of the crystal, a white LED with a color rendering index of 97 was finally successfully fabricated, realizing the leap from basic materials to optoelectronic devices.

Highly Emissive Chiral Mn(II) Bromide Hybrids for UV‐Pumped Circularly Polarized LEDs and Scintillator Image Applications

“…These data are in line with our spectral measurements (vide supra), which reveal that the [MnBr 4 ] 2− anions are actual emissive species in crystals of 1 R / 1 S . Of note, the calculated PDOS distribution is typical of the ionic 0D halomanganates, [ 34–39,44,49 ] whose emission is also stemmed from the isolated [MnX n ] m − anions. Again, the calculated band structure of 1 R / 1 S demonstrates a flatness pattern of both conduction and valence bands which means a highly localized character of the states.…”

“…[30][31][32][33] Of note, a similar pattern was reported for other Mn(II) tetrahalides. [25,[34][35][36][37][38][39][40][41][42][43][44][45] When photoexcited, hybrids 1R and 1S display a strong PL band, the maximum (λ max = 519 nm) and narrow shape (FWHM = 1906 cm −1 ) of which indicates Mn 2+ -centered phosphorescence (Figure 3a). The absence of excitation-dependent behavior (Figure S6, Supporting Information) and monoexponential decay kinetics testify to no other emitting centers in 1R/1S, apart from Mn 2+ ions.…”

Photophysical and Magnetic Properties in Zero-Dimensional (H2DABCO)MX4·nH2O (M = Mn and Cu; X = Cl and Br; n = 0, 1, and 4)

“…Consequently, numerous lead-free hybrid halides have been designed, yet their low stability is their primary shortcoming. − Though researchers employed a transition metal doping strategy to minimize the toxicity, there is doubt regarding its application due to the structural deformation and charge variation . Hence transition metal (Mn 2+ , Cu + , and Cu 2+ ) based hybrid halides have gained substantial attention owing to their low cost and nontoxic nature and their advantage of a large Stokes shift, unlike lead halide perovskites, which suffer from self-absorption. − …”

Mn2+‐Based Luminescent Metal Halides: Syntheses, Properties, and Applications

“…A positive correlation between Mn-Mn distance and PLQY has been demonstrated in the tetrahedral coordination environment, which makes the modulation of PL properties possible. [102,105,[119][120][121][122][123][124][125] 4.1. All-Inorganic Tetra-Coordinated Mn 2+ -Based Metal Halides Cs 3 MnX 5 is one of the typical all-inorganic tetra-coordinated Mn 2+ -based metal halides.…”