Short Aromatic Diammonium Ions Modulate Distortions in 2D Lead Bromide Perovskites for Tunable White-Light Emission

Abstract

White-light broadband emission in the visible range from the low-dimensional halide perovskites is commonly attributed to structural distortions in lead bromide octahedra. In this paper, we report Dion–Jacobson-phase two-dimensional (2D) lead bromide perovskites based on short aromatic diammonium cations, p-phenylene diammonium (pPDA), m-phenylene diammonium (mPDA), and two 1D compounds templated by o-phenylene diammonium (oPDA). All of the compounds exhibit white-light emission. Single-crystal X-ray diffraction analysis reveals that the distortion of the Pb octahedra is influenced by the stereochemistry of the cations and their interactions with the perovskite layers. Solid-state 1H and 207Pb NMR spectroscopy analysis further confirms this trend, whereby different 1H and 207Pb chemical shifts are observed for the pPDA and mPDA spacer cations, indicating different hydrogen-bonding interactions and octahedral distortions. Owing to the octahedral distortion, 2D (mPDA)PbBr4 compounds exhibit broader white-light emission than 2D (pPDA)PbBr4. Density functional theory calculations suggest that (pPDA)PbBr4 and (mPDA)PbBr4 are direct-band-gap semiconductors, and they exhibit larger electronic band gaps and effective masses than the Ruddlesden–Popper-phase (BA)2PbBr4. Among the films of these compounds, 2D (mPDA)PbBr4 shows the best stability, which is attributed to stronger hydrogen-bonding interactions in the material.

Tuning charge carrier dynamics through spacer cation functionalization in layered halide perovskites: an ab initio quantum dynamics study

“…The evaluated carrier lifetime of the nanosecond scale in these layered halide perovskites is also in good agreement with the experimental reports. 81–83…”

“…The evaluated carrier lifetime of the nanosecond scale in these layered halide perovskites is also in good agreement with the experimental reports. [81][82][83] Several intrinsic properties, such as electronic band gap variation, electron-phonon coupling induced non-adiabatic transitions, and quantum decoherence, substantially impact the carrier dynamics in LHPs. 36,84,85 We further explore these key factors for an atomistic understanding of the relationship between structural distortion and excited state charge carrier dynamics.…”

35 Years and 35 Voices from Chemistry of Materials

“…His first manuscript in the journal was on the molten salt synthesis of low-dimensional ternary chalcogenides, opening up the use of alkali-metal polysulfide melts for material discovery broadly . At the time of this writing, his most recent manuscript in the journal examined crystal distortions in lead bromide perovskites with different aromatic diammonium ions . Both the early and more recent research are rich in structure–property analysis toward materials addressing energy and sustainability challenges.…”

“…8 At the time of this writing, his most recent manuscript in the journal examined crystal distortions in lead bromide perovskites with different aromatic diammonium ions. 9 Both the early and more recent research are rich in structure−property analysis toward materials addressing energy and sustainability challenges. He earned his B.S.…”

High-Symmetry Structural Phase Transition Triggers a Triple Switch Based on Dielectric, Nonlinear Optics, and Photoluminescence

“…Furthermore, the distinctive structural properties of two-dimensional (2D) perovskite materials indicate a variety of application possibilities in the area of solid-state lighting. − Blue-light materials and their light-emitting diodes (LEDs), which display as an essential component of the three primary hues, perform a key role in applications in the fields of lighting and flat panels. The quantum efficiency of green-light, red-light, and near-infrared perovskite materials has recently been steadily increased. , However, blue-light perovskite materials, which are effective and reliable as the final crucial building block for white lighting and full-color display applications, are still lagging behind other light hues in comparison. , Most Pb-based organic–inorganic materials have blue-white photoluminescence properties. , So far, few lead-free 2D organic–inorganic materials with blue photoluminescence have been reported. The transition metal Cd 2+ with a d 10 configuration can be used as a luminescent center and can provide almost continuous colors ranging from cool yellow to deep red due to its high color saturation .…”