Scintillators, one of the essential components in medical imaging and security checking devices, rely heavily on rare‐earth‐containing inorganic materials. Here, a new type of organic‐inorganic hybrid scintillators containing earth abundant elements that can be prepared via low‐temperature processes is reported. With room temperature co‐crystallization of an aggregation‐induced emission (AIE) organic halide, 4‐(4‐(diphenylamino) phenyl)‐1‐(propyl)‐pyrindin‐1ium bromide (TPA‐PBr), and a metal halide, zinc bromide (ZnBr2), a zero‐dimensional (0D) organic metal halide hybrid (TPA‐P)2ZnBr4with a yellowish‐green emission peaked at 550 nm has been developed. In this hybrid material, dramatically enhanced X‐ray scintillation of TPA‐P+is achieved via the sensitization by ZnBr42−. The absolute light yield (14,700 ± 800 Photons/MeV) of (TPA‐P)2ZnBr4is found to be higher than that of anthracene (≈13,500 Photons/MeV), a well‐known organic scintillator, while its X‐ray absorption is comparable to those of inorganic scintillators. With TPA‐P+as an emitting center, short photoluminescence and radioluminescence decay lifetimes of 3.56 and 9.96 ns have been achieved. Taking the advantages of high X‐ray absorption of metal halides and efficient radioluminescence with short decay lifetimes of organic cations, the material design paves a new pathway to address the issues of low X‐ray absorption of organic scintillators and long decay lifetimes of inorganic scintillators simultaneously.
Herein, a new family of hybrid metal halides, (DMAP)2MBr4(M = Cu, Zn), featuring zero‐dimensional (0D), pseudo‐layered crystal structures containing isolated molecular 4‐dimethylaminopyridinium (DMAP, C7H11N2+) cations and MBr42−tetrahedral anions are reported. (DMAP)2MBr4show remarkable long‐term stability, with no signs of degradation after one year of ambient air exposure. The reported solution synthesis affords large crystals measuring up to 1 cm, which showed significant response to soft 8 keV X‐ray photons when implemented into X‐ray detectors. Furthermore, (DMAP)2ZnBr4demonstrates tunable color light emission properties, which is attributed to the organic molecular units based on our combined experimental and computational results. The measured photoluminescence quantum yield (PLQY) for (DMAP)2ZnBr4is 7.35 %, a remarkable enhancement of emission efficiency as compared to a weak emission from the organic precursor. The inexpensive and earth‐abundant chemical compositions and ease of preparation of the new hybrid metal halides make them promising candidates for optical and electronic applications.
more » « less- Award ID(s):
- 2045490
- NSF-PAR ID:
- 10446958
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- European Journal of Inorganic Chemistry
- Volume:
- 2022
- Issue:
- 10
- ISSN:
- 1434-1948
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Low‐dimensional (low‐D) organic metal halide hybrids (OMHHs) have emerged as fascinating candidates for optoelectronics due to their integrated properties from both organic and inorganic components. However, for most of low‐D OMHHs, especially the zero‐D (0D) compounds, the inferior electronic coupling between organic ligands and inorganic metal halides prevents efficient charge transfer at the hybrid interfaces and thus limits their further tunability of optical and electronic properties. Here, using pressure to regulate the interfacial interactions, efficient charge transfer from organic ligands to metal halides is achieved, which leads to a near‐unity photoluminescence quantum yield (PLQY) at around 6.0 GPa in a 0D OMHH, [(C6H5)4P]2SbCl5.
In situ experimental characterizations and theoretical simulations reveal that the pressure‐induced electronic coupling between the lone‐pair electrons of Sb3+and the π electrons of benzene ring (lp‐π interaction) serves as an unexpected “bridge” for the charge transfer. Our work opens a versatile strategy for the new materials design by manipulating the lp‐π interactions in organic–inorganic hybrid systems. -
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Abstract Low‐dimensional (low‐D) organic metal halide hybrids (OMHHs) have emerged as fascinating candidates for optoelectronics due to their integrated properties from both organic and inorganic components. However, for most of low‐D OMHHs, especially the zero‐D (0D) compounds, the inferior electronic coupling between organic ligands and inorganic metal halides prevents efficient charge transfer at the hybrid interfaces and thus limits their further tunability of optical and electronic properties. Here, using pressure to regulate the interfacial interactions, efficient charge transfer from organic ligands to metal halides is achieved, which leads to a near‐unity photoluminescence quantum yield (PLQY) at around 6.0 GPa in a 0D OMHH, [(C6H5)4P]2SbCl5.
In situ experimental characterizations and theoretical simulations reveal that the pressure‐induced electronic coupling between the lone‐pair electrons of Sb3+and the π electrons of benzene ring (lp‐π interaction) serves as an unexpected “bridge” for the charge transfer. Our work opens a versatile strategy for the new materials design by manipulating the lp‐π interactions in organic–inorganic hybrid systems. -
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Abstract The photophysical tuning is reported for a series of tetraphenylphosphonium (TPP) metal halide hybrids containing distinct metal halides, TPP2MX
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