Smart Materials and Structures
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2022
·Vol. 32
·期 1
·015019
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IF 4.131
Jian Gao,Kangning Wu,Jianying Li,Guilai Yin,Shengtao Li
In this study, an all-organic lead-free thermochromic and dielectric switchable epoxy microcomposite (TEP) is presented from singly incorporating leuco dye microcapsule materials (LDM) into the epoxy matrix. TEP can simultaneously adjust the color and permittivity in response to temperature between 30 °C and 70 °C. Moreover, the switchable dielectric behavior of TEP can be manipulated by LDMs content and voltage frequency. The switchable dielectric behavior of TEP permittivity is proposed to originate from the inner interfacial polarizations in LDMs triggered by the order-disorder phase transition. Before the phase transition, the molecules in LDMs are in ordered and compact arrays with restricted mobility, which can hardly undergo transportations and reorientations, leading to the weak interfacial polarization strength at the inner surfaces of LDMs and the low permittivity of TEP. After the phase transition, the molecules in LDMs are liberated with enhanced intermolecular distances and mobility, facilitating the inner interfacial polarization in LDMs and leading to the high permittivity of TEP. The correlation between the switchable dielectric behavior and the order-disorder phase transition is furtherly verified based on the Lichtenecker's mixing model. This study unlocks a novel function of switchable permittivity for the LDM materials and provides an innovative strategy for designing the thermochromic and dielectric switchable smart materials.
研究领域:
材料科学
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智能材料
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2022
·Vol. 33
·期 9
·2210481
·
IF 19.924
Shihai You,Tingting Zhu,Yumin Wang,Zeng-Kui Zhu,Zhongyuan Li,Jianbo Wu,Panpan Yu,Lina Li,Chengmin Ji,Yaxing Wang,Shuao Wang,Junhua Luo
The exceptional photophysical properties of 3D organic–inorganic lead halide hybrids (OILHs) endow their significant potential for usage in optoelectronics, which has sparked intense research on novel 3D OILHs and associated applications. However, constructing new 3D OILHs based on large organic cations suffers from tough challenges due to the limitation of the Goldschmidt tolerance factor rule, let alone further explorations of their practical applications. Herein, a brand-new 3D lead chloride hybrid, (1MPZ)Pb 4 Cl 10 ·H 2 O ( 1 , 1MPZ = 1-methylpiperazine) is reported, featuring a dense 3D lead chloride framework made of the corner-, edge-, and face-shared lead chloride polyhedra. 1 presents a broadband white light emission with a large Stokes shift and a nanosecond photoluminescence lifetime, which originates from radiative recombination of self-trapped excitons (STEs) induced by the highly distorted structure. Such a reabsorption-free and fast-decayed STEs emission coupling with the dense 3D architecture further enables 1 with effective X-ray scintillation with good sensitivity. Impressively, 1 also shows superior environmental and radiation stability. This study provides a new 3D OILH with appealing luminescence, not only expanding the 3D OILH family but also inspiring the exploitation of their optoelectronic applications.
研究领域:
材料科学
·
光学
·
辐射探测
✓ 已验证
DOI
高影响因子
ACS Nano
·
2019
·
IF 13.903
Jiaqi Ma,Chen Fang,Chao Chen,Long Jin,Jiaqi Wang,Shuai Wang,Jiang Tang,Dehui Li
Chiral materials are of particular interest and have a wide range of potential applications in life science, material science, spintronic, and optoelectronic devices. Two-dimensional (2D) hybrid organic–inorganic lead halide perovskites have attracted increasing attention. Incorporating the chiral organic ligands into the layered lead iodide frameworks would introduce strong chirality in pure 2D perovskites for potential applications in circularly polarized light (CPL) emission and detection; nonetheless, studies on those aspects are still in their infancy. Here, we report on the strong CPL emission and sensitive CPL detection in the visible-wavelength range in pure chiral (R-/S-MBA)2PbI4 (MBA = C6H5C2H4NH3) 2D perovskites, which are successfully synthesized with a needle shape and millimeter size by incorporating the chiral molecules. The chiral 2D perovskites (R-MBA)2PbI4 and (S-MBA)2PbI4 exhibit an average degree of circularly polarized photoluminescence (PL) of 9.6% and 10.1% at 77 K, respectively, and a maximum degree of the circularly polarized PL of 17.6% is achieved in (S-MBA)2PbI4. The degree of circularly polarized PL dramatically decreases with increasing temperature, implying that the lattice distortion induced by the incorporated chiral molecules and/or temperature-dependent spin flipping might be the origin for the observed chirality. Finally, CPL detection has been achieved with decent performance in our chiral 2D perovskite microplate/MoS2 heterostructural devices. The high degree of the circularly polarized PL and excellent CPL detection together with the layered nature of pure chiral 2D perovskites enables them to be a class of very promising materials for developing and exploring spin associated electronic devices based on the chiral 2D perovskites.
研究领域:
材料科学
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光电子学
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自旋电子学
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纳米技术
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物理化学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry C
·
2020
·Vol. 8
·期 29
·9968-9974
·
IF 7.059
Hui Xiao,Yi Wei,Peipei Dang,Shuang Liang,Ziyong Cheng,Guogang Li,Jun Lin
Perovskite nanocrystals (NCs) have aroused wide interest in the field of optoelectronics. Herein, a quantitative post-processing method is proposed to precisely alter the photoluminescence of lead halide perovskite NCs by ligand substitution using a multidentate multifunctional polymer ligand with amide, carboxylic acid and terminal double bond groups. Surprisingly, the synergistic effect of the ligand leads to a continuously blue-shifted emission over a wide visible region (∼100 nm) with increasing addition of the polymer ligand. Moreover, the full width at half maximum (fwhm) also gradually narrows, indicating the formation of a uniform particle size after the ligand surface interaction. Simultaneously, the terminal double bonds can be cross-linked with styrene to protect perovskite NCs from moisture. These results provide a new route for controllable photoluminescence regulation and preliminarily explore the correlation between the luminescence properties of perovskite NCs and polymer ligands.
研究领域:
材料科学
·
光电子学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）