Exploration
·
2024
·
IF 0
Heng Guo,Linlin Shi,Zengliang Shi,Yue He,Yizhi Zhu
Yellow light-emitting diodes (LEDs) with a wavelength of 570–590 nm can reduce the excitability of peripheral nerves and the sensitivity of the skin, stimulate collagen synthesis, and tighten the skin, which plays an important role in skin rejuvenation. In general, commercial LEDs are made of phosphor excited by ultraviolet chips. It is very important for the development of yellow light emitters with high luminous efficiency, good stability, and environmental protection. For the first time, a simple organic structural unit (2-methylimidazole, 2-MIM) was used to collect a mixture of two metal precursors (CsI and CuI) and successfully synthesized an all-inorganic lead-free yellow light CsCu 2 I 3 powder in water. The prepared CsCu 2 I 3 powder exhibited excellent optical properties and considerable stability. Finally, a phosphor-converted LED (pc-LED) device was fabricated via the CsCu 2 I 3 phosphor coated on a 310 nm ultraviolet chip. The pc-LED device's electroluminescence spectra may be a good fit for the blood's absorption regions. Therefore, this work provides a facile method for the synthesis of novel lead-free metal halide CsCu 2 I 3 powder in eco-friendly solvents. In addition, the stable and efficient CsCu 2 I 3 powder shows promising exciting potential applications in photoluminescence and phototherapy fields.
研究领域:
材料科学
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光学
·
生物医学工程
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DOI
Journal of Materials Chemistry C
·
2021
·Vol. 10
·期 1
·204-209
·
IF 7.393
Xiaoxia Liu,Chengdong Peng,Lijie Zhang,Daying Guo,Yuexiao Pan
As an all-inorganic zero-dimensional (0D) lead-free metal halide, Cs2ZnCl4 is a potentially excellent matrix for preparing chemically stable and environmentally friendly photoluminescent materials through an ion-doping strategy. Therefore, it is necessary to study the emission properties of every kind of doping ion in the tetrahedral coordination of Cs2ZnCl4. Here, for the first time, we successfully synthesized Te4+-doped Cs2ZnCl4 single crystals via a facile hydrothermal method. X-ray crystallography clearly reveals the strong distortion of the tetrahedral units in Cs2ZnCl4 caused by doping with Te4+. Broadband yellow-light emission covering the range from 450 nm to 700 nm with a large Stokes shift is observed in Cs2ZnCl4:Te4+ single crystals, and this is attributed to self-trapped excitons (STEs) caused by the lattice vibration of the distorted structure. It is worth mentioning that this broadband yellow phosphor can be excited by a wide range of blue light, implicitly giving it an excellent ability to adapt to multiple models of blue LED chips, thus serving as a suitable yellow phosphor that can be applied to fabricate WLEDs without the need to worry about the lack of red light.
研究领域:
材料科学
·
光学
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产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2021
·Vol. 9
·期 40
·14217-14225
·
IF 7.393
Junyi Huang,Chen Dong,Yantao Mei,Xiayao Lu,Gentian Yue,Yueyue Gao,Rong Liu,Weifeng Zhang,Furui Tan
Lead-free metal halide perovskites have attracted extensive attention as promising optoelectronic semiconductors with environmental friendliness. Cs2SnI6, a double perovskite with both a good phase and composition stability, is an appealing candidate for potential application in optoelectronic devices. To date, few reports have focused on the facile fabrication of dense and uniform Cs2SnI6 films that are key components for optoelectronic devices. Herein, a simple and low-cost solution method is reported to prepare densely packed Cs2SnI6 thin films. It was found that strategic precursor-compensation treatment (PCT) of the as-prepared spin-coated Cs2SnI6 thin films compensates the evaporation loss of volatile SnI4 and thus allows for pinhole-free and pure-phase double perovskite. The modified n-type Cs2SnI6 double perovskite shows enhanced conductivity and mobility with decreased charge recombination loss. As a result, the applied photodetectors show an enhanced photocurrent gain of 151 compared to that of 88 for the control sample. The responsivity (control 0.0059 mA W−1 to target 1.07 mA W−1) and detectivity (control 2.94 × 1010 Jones to target 6.03 × 1010 Jones) of the device were significantly improved in the self-powered mode. In addition, the PCT-Cs2SnI6 photodetectors show excellent long-time stability with 98% initial detectivity retained after storing in ambient environment for 28 days. This study paves the way for the preparation of high-quality Cs2SnI6 films for application in efficient optoelectronic devices.
研究领域:
材料科学
·
光电材料
·
半导体物理
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产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2022
·Vol. 33
·期 5
·2210735
·
IF 19.924
Binbin Su,Jiance Jin,Kai Han,Zhiguo Xia
Scintillators with high light yield, low detection limit, large X-ray attenuation efficiency as well as stable and nontoxic compositions are of great importance for radiation detection applications. Here, 0D (C 8 H 20 N) 2 Cu 2 Br 4 single crystals are obtained and show blue emission peaking at 468 nm with a near-unity photoluminescence quantum yield of 99.7%, a large Stokes shift of 148 nm (i.e., negligible self-absorption), and a good environmental stability along with strong X-ray absorption capability. Moreover, a high light yield of up to ≈ 91 300 photons/MeV and a low detection limit of 52.1 nGy air s −1 are realized, which is more than one hundred times lower than the dose rate of 5.5 µGy air s −1 required for X-ray medical diagnostics. (C 8 H 20 N) 2 Cu 2 Br 4 ceramic wafer scintillation screen is fabricated by a cold pressing sintering process, and the clear contrast images of opaque metal box and electronic component with a spatial resolution of 9.54 lp mm −1 are realized. This study not only designs a new lead-free metal halide scintillator, but also develops a universal strategy for the preparation of large-sized scintillator screen in nondestructive X-ray imaging.
研究领域:
材料科学
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辐射检测
·
医学成像
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产品关联
DOI
高影响因子
Materials Horizons
·
2025
·
IF 10.7
Jianhui Zhao,Yunsong Di,Yuhang Sheng,Jiaxin Sui,Xingru Yang,Yi Zhang,Ying Wang,Haoyu Wang,Xiaowei Zhang,Liyan Yu,Zhihui Chen,Zhixing Gan
Given that optical thermometers are widely used due to their unique advantages, this study aims to address critical challenges in existing technologies, such as insufficient sensitivity, limited temperature measurement ranges, and poor signal recognition capabilities. Herein, we develop a thermometer based on the fluorescence intensity ratio (FIR) of Sb-doped Cs2NaInCl6 (Cs2NaInCl6:Sb). As the temperature increases from 203 to 323 K, the thermally induced transition from triplet to singlet self-trapped excitons (STEs) leads to enhanced 455 nm photoluminescence (PL) from singlet STE recombination. Thus, the FIR monotonically depends on temperature, allowing for temperature sensing with a high absolute sensitivity (SA) of 0.0575 K−1 and the maximum relative sensitivity (SR) of 1.005% K−1. We demonstrate that spatial temperature distribution can be measured by mapping the PL spectra, even with a transparent medium screening the target. Furthermore, blue emissive Cs2NaInCl6:Sb is mixed with yellow emissive Cs2AgInCl6:Sb with a thermal quenching feature. The fluorescence color of the mixture dramatically depends on temperature, enabling a user-friendly colorimetric temperature sensing. Therefore, two operational modes are proposed to meet various practical application demands.
研究领域:
材料科学
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光学工程
·
物理化学
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产品关联
DOI
PubMed
高影响因子
Advanced Science
·
2022
·Vol. 9
·期 22
·2202123
·
IF 17.521
Ying Li,Jiahui Wang,Qing Yang,Guozhen Shen
Optoelectronic synapses combining optical-sensing and synaptic functions are playing an increasingly vital role in the neuromorphic computing systems development, which can efficiently process visual information and complex recognition, memory, and learning. Metal halides are considered promising candidates for synaptic devices due to their excellent optoelectronic properties. However, the toxicity of lead and the further development of device functions are the recognized problems at present. Herein, a flexible optoelectronic synapses system based on high-quality lead-free Cs 3 Bi 2 I 9 nanocrystals is demonstrated, in which the carrier confinement caused by the band mismatching between the Cs 3 Bi 2 I 9 and the organic semiconductor layer provides the possibility to simulate synaptic behaviors. The synaptic functions including long/short-term memory and learning-forgetting-relearning are demonstrated in this device and visual perception, visual memory, and color recognition functions are successfully implemented. Additionally, the flexible device exhibits excellent robustness and can realize imaging of light distribution under curved hemispheres similar to the human eye. Finally, through the simulation based on an artificial neural network algorithm, the device successfully realizes the high-precision recognition of handwritten digital images and possesses a strong fault tolerant capability even in bending states. These results are expected to drive the practical progress of metal halide for neuromorphic computing.
研究领域:
材料科学
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神经科学
·
人工智能
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Lei Zhou,Lei Zhang,Yuanyuan Chang,Ming Li,Rongxing He
Emerging low-dimensional metal halides have attracted enormous research interests due to their prominent photoluminescence (PL) properties and extensive application potentials. However, the systematic discussion on the structure-luminescence-stability relationship is still lacking. Herein, a series of novel lead-free metal halides are developed to unveil the underlying relationship. The as-synthesized (C 6 H 5 NH 3 ) 6 SbCl 9 ·H 2 O single crystal is structurally unstable that would spontaneously transform into (C 6 H 5 NH 3 ) 3 ClSbCl 5 ·H 2 O in the mother liquor, due to the strong antibonding Sb-5s 2 lone pair with a spherical distribution in highly symmetrical geometry. To suppress this effect and stabilize the metastable phase, In 3+ without ns electrons is introduced into the lattice of (C 6 H 5 NH 3 ) 6 SbCl 9 ·H 2 O, as a result, the changed coordination environment, including band structure, lattice constant and intermolecular electronic interaction, not only inhibits the structure transformation, but also leads to an enhanced PL efficiency (83.37 %) at ∼ 600 nm. This work promotes the understanding of structure-luminescence-stability relationship in organic–inorganic materials, and provides a new insight for further searching for high-performance lead-free perovskite luminescent materials.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
·
2025
·
IF 4.7
Lingkang Yu,Yining Wang,Xiaole Xing,Zheng Xu,Mengmeng Shang
Presently, a multitude of all-inorganic and lead-free metal halide perovskites are chosen as matrices for Cr3+ doping due to their favorable coordination environments, aiming to achieve a near-infrared (NIR) emission. Nonetheless, the acquisition of a more efficient NIR emission remains challenging. Herein, we successfully enhanced NIR luminescence within the Cs2ScCl5·H2O:Cr3+ by codoping Te4+ ions. The weak symmetry of Cs2ScCl5·H2O provides an appropriate crystal environment for the broadband near-infrared emission of Cr3+. The NIR emission from the 4T2 → 4A2 transition of Cr3+ is significantly enhanced due to the energy transfer by the emission of STEs, with a photoluminescence quantum yield (PLQY) of 11.02%. Compared to single doping with Cr3+, the emission intensity of Cs2ScCl5·H2O:Cr3+, Te4+ in the NIR region obtains a 3-fold enhancement, while a new yellow emission is simultaneously obtained. This discovery offers a viable method for achieving efficient NIR emission in lead-free metal halides via codoping with ns2 ions and Cr3+. Additionally, Cs2ScCl5·H2O:Cr3+, Te4+ sample was combined with a 380 nm violet light chip for encapsulation, demonstrating its potential applications in the fields of nondestructive material testing and night vision.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials Today Chemistry
·
2025
·
IF 6.7
Heng Guo,Zhuxin Li,FangFang Zhang,Jiajun Ma,Yizhi Zhu,Xian Wei,Xiaofei Liu
The discovery of lead-free low-dimensional metal halides has provided a viable approach for developing air-stable and environmentally friendly optoelectronic devices. This study presents the low-temperature preparation of lead-free CsAgBr 2 single crystals, along with a detailed structural and stability characterization. It also reveals their initial application in ultraviolet photodetectors. These crystals have a low-dimensional crystal structure and exceptional chemical stability, allowing for long-term storage under ambient conditions. A comprehensive characterization of CsAgBr 2 single crystals was carried out using X-ray diffraction and optical absorption measurements to determine their fundamental properties. The material exhibits strong ultraviolet (UV) light absorption, and the fabricated photodetectors demonstrate excellent UV detection performance. These features demonstrate the potential of one-dimensional all-inorganic CsAgBr 2 as an eco-friendly, cost-effective, and the performance of UV photodetector.
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产品关联
DOI
高影响因子
Materials Horizons
·
2022
·Vol. 9
·期 5
·1479-1488
·
IF 15.717
Can Zou,Qing Liu,Kai Chen,Fei Chen,Zixuan Zhao,Yunxuan Cao,Congcong Deng,Xingfu Wang,Xiaohang Li,Shaobin Zhan,Fangliang Gao,Shuti Li
Polarization-sensitive photodetectors are the core of optics applications and have been successfully demonstrated in photodetectors based on the newly-emerging metal-halide perovskites. However, achieving high polarization sensitivity is still extremely challenging. In addition, most of the previously reported photodetectors were concentrated on 1D lead-halide perovskites and 2D asymmetric intrinsic structure materials, but suffered from being external bias driven, lead-toxicity, poor stability and complex processes, severely limiting their practical applications. Here, we demonstrate a high-performance polarization-sensitive and stable polarization-sensitive UV photodetector based on a dendritic crystal lead-free metal-halide CsCu2I3/GaN heterostructure. By combining the anisotropic morphology and asymmetric intrinsic structure of CsCu2I3 dendrites with the isotropic material GaN film, a high specific surface area and built-in electric field are achieved, exhibiting an ultra-high polarization selectivity up to 28.7 and 102.8 under self-driving mode and −3 V bias, respectively. To our knowledge, such a high polarization selectivity has exceeded those of all of the reported perovskite-based devices, and is comparable to, or even superior to, those of the conventional 2D heterostructure materials. Interestingly, the unsealed device shows outstanding stability, and can be stored for over 2 months, and effectively maintained the performance even after repeated heating (373K)-cooling (300K) for different periods of time in ambient air, indicating a remarkable temperature tolerance and desired compatibility for applications under harsh conditions. Such excellent performance and simple method strongly show that the CsCu2I3/GaN heterojunction photodetector has great potential in practical applications with high polarization-sensitivity. This work provides a new insight into designing novel high-performance polarization-sensitive optoelectronic devices.
研究领域:
材料科学
·
光学工程
·
电子器件
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2023
·Vol. 25
·期 45
·30993-31002
·
IF 3.3
Siqi Dai,Xiaoyan Gan,Kegui Li,Qiang Huang,Liling Guo,Hanxing Liu
Lead-free metal halide perovskites have received widespread attention due to their composition of minimal hazardous components, excellent air stability, and long carrier lifetimes. However, the majority of the lead-free metal halide perovskites, such as Cs3Bi2Br9, have wide bandgaps, which limits their photoelectric in solar cells and optoelectronic devices. To address this issue, attempts have been made to adjust the bandgap through material alloying. Based on a solution approach, a pure phase of Cs3Bi2−xSbxBr9 crystals has been synthesized, with the alloying parameter x changing over the full range of composition. It is found that the mixed alloy has a smaller bandgap than pure Bi-based and Sb-based perovskites, with the smallest bandgap of 2.22 eV near x = 1, and there is a phenomenon of bandgap bowing throughout the alloying process. The electronic structure of Cs3Bi2−xSbxBr9 has been investigated using DFT calculations and the bandgap bowing of Cs3Bi2−xSbxBr9 is deduced to be related to the type-II band alignment between the Cs3Bi2Br9 and Cs3Sb2Br9. Owing to the mismatch of s and p orbital energies of Bi and Sb, the mixed alloy has a smaller bandgap. Our work demonstrated a method for achieving bandgap reduction and explained the phenomenon of bandgap bowing by pairing materials into type-II band alignment, which may also be found in other lead-free metal perovskites.
研究领域:
材料科学
·
物理学
·
化学
·
太阳能
✓ 已验证
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2023
·Vol. 33
·期 47
·2305858
·
IF 19
Shuangyi Zhao,Zhenglin Jia,Yian Huang,Qingkai Qian,Qianqian Lin,Zhigang Zang
Lead-free metal halides have recently received sustained attention because of their nontoxicity, low-cost, as well as excellent stability and optoelectronic properties. However, most of the reported lead-free metal halides are synthesized via slow solution-processing at high temperature in toxic solvents, which may impede their commercial applications. Here, a solvent-free strategy is proposed to synthesize inorganic rubidium copper halides (Rb 2 CuX 3 , X = Cl, Br) at room temperature, which exhibit efficient violet emission dominated by a self-trapped excitons (STEs) mechanism and attractive stabilities against ultraviolet illumination and heating. Thus, Rb 2 CuX 3 powders are employed as emitters and scintillators applied in wireless light communication and X-ray imaging technologies. Under orthogonal frequency division multiplexing modulation, emitters demonstrate a broad −3 dB bandwidth of 26.3 MHz and a high received data rate of 205.1 Mbps. Additionally, flexible scintillation films based on as-prepared powders are fabricated and show outstanding X-ray scintillation properties, including a high spatial resolution of 18.1 lp mm −1 and a low detection limit of 104 nGy air s −1 , as well as promising imaging performance for irregular objects. These results suggest large-scale production of nontoxic Rb 2 CuX 3 and their potential commercialization in fields of high-speed light communication and X-ray radiography.
研究领域:
材料科学
·
光电技术
·
通信技术
·
放射成像
✓ 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）