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Abstract Zero‐dimensional (0D) organic metal halide hybrids (OMHHs) are emerging materials with significant potential for optoelectronic applications, including direct X‐ray detectors. While 0D OMHH single crystals exhibit excellent X‐ray detection properties, their scalability remains a significant challenge due to the time‐intensive growth process and difficulty in producing large single crystals exceeding a few centimeters. This limitation hinders their practicality for large‐area detector applications. Here, we report for the first time the development of amorphous 0D OMHH films via solution processing for efficient direct X‐ray detection. By reacting a non‐crystalline organic halide, triphenyl(9‐phenyl‐9H‐carbazol‐3‐yl)phosphonium bromide (TPPCarzBr), with zinc bromide (ZnBr2), we have successfully produced amorphous 0D (TPPCarz)2ZnBr4films with controlled thickness via facile solution processing. The organic cations (TPPCarz⁺) feature a lower bandgap than the ZnBr42−anions, enabling efficient molecular sensitization, where ZnBr42−anions serve as X‐ray absorbers and TPPCarz⁺ cations as charge transporters. Direct X‐ray detectors based on 0D (TPPCarz)2ZnBr4films demonstrate outstanding performance, achieving a stable X‐ray detection sensitivity of 2,165 µC Gyair⁻1cm⁻2at 20 V mm⁻¹ and a detection limit of 6.01 nGyair s⁻¹. The amorphous nature of these films enhances their processability, allowing for fabrication in various sizes and shapes, and making them highly adaptable for scalable detector applications.
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A Zero‐Dimensional Organic Seesaw‐Shaped Tin Bromide with Highly Efficient Strongly Stokes‐Shifted Deep‐Red Emission
Abstract The synthesis and characterization is reported of (C9NH20)2SnBr4, a novel organic metal halide hybrid with a zero‐dimensional (0D) structure, in which individual seesaw‐shaped tin (II) bromide anions (SnBr42−) are co‐crystallized with 1‐butyl‐1‐methylpyrrolidinium cations (C9NH20+). Upon photoexcitation, the bulk crystals exhibit a highly efficient broadband deep‐red emission peaked at 695 nm, with a large Stokes shift of 332 nm and a high quantum efficiency of around 46 %. The unique photophysical properties of this hybrid material are attributed to two major factors: 1) the 0D structure allowing the bulk crystals to exhibit the intrinsic properties of individual SnBr42−species, and 2) the seesaw structure enabling a pronounced excited state structural deformation as confirmed by density functional theory (DFT) calculations.
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- PAR ID:
- 10048589
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 57
- Issue:
- 4
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 1021-1024
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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