Journal of the American Chemical Society
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2024
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IF 14.4
Xiaoyu Song,Xinsheng Liu,Danwen Zhang,Jingyan Liao,Siqi Zhu,Wei Zheng
Two-dimensional organic–inorganic hybrid layered perovskites have emerged as a new generation of optoelectronic materials. However, the thermochromism in organic–inorganic hybrid layered perovskites has been rarely explored in depth. A further understanding of the mechanism is necessary and favorable for the application. Here, transparent centimeter-sized single crystals of the organic–inorganic hybrid layered perovskite (C6H5C2H4NH3)2PbBr4 (PEA2PbBr4) were synthesized using an improved evaporation method. As a typical organic–inorganic hybrid layered perovskite, the PEA2PbBr4 single crystal shows high-contrast and progressive thermochromism exhibiting a change from colorlessness and transparency to lemon yellow in a wide temperature range of 200–450 K. Based on the calculation through the Varshni equation, the temperature-induced bandgap change rate directly associated with the high-contrast thermochromism of PEA2PbBr4 reaching 0.8 meV/K. This value is higher than that of many three-dimensional perovskites and traditional IV–III semiconductors. Furthermore, the temperature-dependent 193 nm photoluminescence spectra suggest that this high temperature-induced bandgap change rate of PEA2PbBr4 is a result of the competitive interaction between lattice thermal expansion and electron–phonon coupling (Fröhlich coupling coefficient ΓLO = 2.215). Based on the characteristics introduced above, PEA2PbBr4 as an organic–inorganic hybrid layered perovskite has a better performance in achieving the balance between high-contrast and high room-temperature transmittance. Therefore, PEA2PbBr4 is a material with great potential in applications like temperature-indicating labels. This work provides valuable insights into the thermochromism of layered perovskites, offering a new material system and approach for developing thermochromic materials with higher sensitivity and efficiency.
研究领域:
材料科学
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光学
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半导体物理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2024
·
IF 10.7
Hao Dong,Xin Liu,Hu Wang,Zhilong Chen,Fenghua Li,Pengxiang Wang,Jie Fu,Yuchuan Shao
Achieving a lower detection limit is always crucial for X-ray detectors in medical imaging. Two-dimensional (2D) perovskites are superior candidate materials for X-ray detection due to their high bulk resistivity, excellent environmental stability, and negligible ion migration under high bias. However, the reported detection limit of 2D perovskite X-ray detectors still apparently lags behind that of their 3D analogues due to the difficulty in the growth of high-quality bulk 2D perovskite single crystals (SCs). Herein, we demonstrate an X-ray detector with an ultra-low detection limit based on high-quality bulk PEA2PbBr4 SCs grown in HBr solution for the first time. According to the solubility difference of reactants, a slowly varying nucleation curve for the precursor solution is designed to stabilize growth rate and reduce defect density during crystal growth. The fabricated Au/PEA2PbBr4/Au detector shows a low noise level of 10−5 nA Hz−1/2 and an ultra-low dark current drift of 6.6 × 10−7 pA cm−1 V−1 s−1. Together with a commendable hole lifetime of 2.76 μs and hole mobility-lifetime product of 5.8 × 10−4 cm2 V−1, the produced detector exhibits a high sensitivity of 2998 μC Gyair s−1 cm−2 and a record-low detection limit of 0.79 nGyair s−1. The current work would be beneficial for the development of next generation medical imaging.
研究领域:
材料科学
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医学成像
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产品关联
DOI
高影响因子
NATURE MATERIALS
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2022
·Vol. 21
·期 9
·1042-1049
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IF 47.656
Zhu Zhaohua,Zhu Chao,Yang Lei,Chen Qian,Zhang Linghai,Dai Jie,Cao Jiacheng,Zeng Shaoyu,Wang Zeyi,Wang Zhiwei,Zhang Wei,Bao Jusheng,Yang Lijuan,Yang Yang,Chen Bo,Yin Chunyang,Chen Hong,Cao Yang,Gu Hao,Yan Jiaxu,Wang Nana,Xing Guichuan,Li Hai,Wang Xiaoyong,Li Shaozhou,Liu Zheng,Zhang Hua,Wang Lin,Huang Xiao,Huang Wei
Formation of epitaxial heterostructures via post-growth self-assembly is important in the design and preparation of functional hybrid systems combining unique properties of the constituents. This is particularly attractive for the construction of metal halide perovskite heterostructures, since their conventional solution synthesis usually leads to non-uniformity in composition, crystal phase and dimensionality. Herein, we demonstrate that a series of two-dimensional and three-dimensional perovskites of different composition and crystal phase can form epitaxial heterostructures through a ligand-assisted welding process at room temperature. Using the CsPbBr 3 /PEA 2 PbBr 4 heterostructure as a demonstration, in addition to the effective charge and energy transfer across the epitaxial interface, localized lattice strain was observed at the interface, which was extended to the top layer of the two-dimensional perovskite, leading to multiple new sub-bandgap emissions at low temperature. Given the versatility of our strategy, unlimited hybrid systems are anticipated, yielding composition-, interface- and/or orientation-dependent properties.
研究领域:
材料科学
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纳米技术
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光伏技术
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半导体物理
✓ 已验证
DOI
PubMed
高影响因子
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