DALTON TRANSACTIONS
·
2023
·Vol. 52
·期 9
·2619-2630
·
IF 4
Xuejiao Wang,Xiaowen Feng,Maxim S. Molokeev,Huiling Zheng,Qiushi Wang,Chunyan Xu,Ji-Guang Li
Phosphors that exhibit tunable broadband emissions are highly desired in multi-functional LEDs, including pc-WLEDs and pc-NIR LEDs. In this work, broadband emissions were obtained and modulated in the unexpectedly wide spectral range of 517–609 nm for (Lu0.99−xGdxBi0.01)2WO6 phosphors by tuning the Gd3+ content (x = 0–0.99). The effects of Gd3+ doping on phase constituents, particle morphology, crystal structure, and photoluminescence were systematically investigated. Broadband green emission was obtained from Gd3+-free (Lu0.99Bi0.01)2WO6 phosphors (x = 0), whose emission intensity was enhanced by 50% with 5 at% Gd3+ (x = 0.05). The phase transition happened when x > 0.50 and the broadband red-NIR emission was obtained when x = 0.75–0.99. Three luminescence centers were proved to be responsible for the broadband green emissions via crystal structure, spectral fitting and fluorescence decay analysis. A pc-WLED with a high color rendering index (Ra = 91.3), a stable emission color, and a low color temperature (3951 K) was fabricated from the (Lu0.94Gd0.05Bi0.01)2WO6 broadband green phosphor, and an LED device that simultaneously emits high color rendering index white light and NIR light was obtained with the (Gd0.99Bi0.01)2WO6 broadband red-NIR phosphor. Night vision and noninvasive imaging were also demonstrated using the latter LED device.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APL Materials
·
2022
·Vol. 10
·期 4
·
IF 6.635
Wang Mengrou,Xu Yubing,Wang Xin,Li Yuwei,Zhao Jingda,Pan Yuzhu,Chen Jing,Li Qing,Zhao Zhiwei,Wu Jun,Lei Wei
All-inorganic halide semiconductors with perovskite or perovskite-like structure have aroused a widespread concern recently for its environmental friendliness and stabilities while possessing excellent optoelectronic properties. Double perovskite Cs 2 AgBiBr 6 single crystal (SC) is one of the most representative materials in the latest research area. To further improve the device response range and decrease its dark current density effectively, functional layers based on the solution-processed epitaxial method are normally fabricated as heterojunctions. Herein, a novel idea of a broadband heterojunction MAPbI 3 (MA = CH 3 NH 3 )/Cs 2 AgBiBr 6 is proposed in this work to achieve this goal. A MAPbI 3 layer is fabricated on Cs 2 AgBiBr 6 SC substrates through immersing Cs 2 AgBiBr 6 SC into MAPbI 3 solution at a MAPbI 3 crystallization temperature. Ultimately, this heterojunction device expands the absorption limit from 618 to 838 nm, makes responsivity range redshift from 629 to 860 nm, and achieves a responsivity of 16.8 mA W −1 while the detectivity of 1.33 × 10 11 Jones under 622 nm 0.55 mW cm −2 illumination at −20 V bias, maintaining excellent optoelectronic properties.
研究领域:
材料科学
·
光电材料
·
半导体物理
✓ 已验证
DOI
高影响因子
ACS Photonics
·
2024
·
IF 6.5
Silu Peng,Chaoyi Zhang,Xianchao Liu,Jiayue Han,Chunyu Li,Hongxi Zhou,He Yu,Chao Chen,Jun Gou,Jun Wang
PbSe is one of the most representative materials in lead chalcogenide semiconductors, possessing a narrow bandgap and demonstrating excellent absorption and photoresponse. However, undoped PbSe typically exhibits low carrier concentrations, along with large dielectric constants and thermal expansion coefficients, imposing limitations on its application in a high-performance photodetector. Doping is an effective strategy to overcome the inherent defects and enhance the optical and electrical properties. In this study, different compositions of Pb1−xLaxSe samples were obtained through solid-phase method doping with the rare earth element La. The doped Pb0.7La0.3Se showed superior optical and electrical properties and photoresponse. Additionally, based on the approach of constructing heterojunctions with thin films and two-dimensional (2D) materials, a self-powered p−n heterojunction photodetector, Pb0.7La0.3Se/WSe2, has been successfully fabricated. The device exhibited a continuous and stable light response from 405 to 1550 nm. Moreover, under 0 V bias and 650 nm laser irradiation, the device achieved the responsivity and specific detectivity of 22.85 A/W and 1.81 × 1012 Jones, along with a rapid response/recovery time (162/135 μs), demonstrating excellent photovoltaic effects and outstanding photodetection performance. The construction of heterojunctions with film and 2D materials provides a novel approach to achieving high-performance photodetectors. Simultaneously, the Pb0.7La0.3Se/WSe2 detector shows enormous potential in the field of superior photodetectors with a high on/off ratio, low noise, broadband, rapid response, and miniaturization.
研究领域:
材料科学
·
光电技术
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2018
·Vol. 11
·期 5
·791
·
IF 2.467
Junping Ding,Huanchun Wang,Haomin Xu,Lina Qiao,Yidong Luo,Yuanhua Lin,Cewen Nan
High efficiency photocatalyst Bi2O2(CO3)1−xSxwas synthesized conveniently with chemical bath precipitation using Bi2O2CO3as the precursor. The microstructures of the samples are systematically characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS) and UV-Vis spectroscopy; the optical and photocatalytic properties are carefully tested as well. The content ofS, which was tuned through the controlling of the precipitation process, was verified to have an intense effect over the photocatalytic properties. A nearly saturatedSratio and the best photocatalytic performance were observed in specimens with the mostScontent. Our study reveals that, with negligible influence of the morphology and crystal structure, Bi2O2(CO3)1−xSxpossessed a broadened optical absorption regionfromultraviolet to visible light, and enhanced photocatalytic activity in comparison to precursor Bi2O2CO3in photocatalytic degradation of Congo Red aqueous solution.Keywords:Bi2O2CO3;Bi2O2(CO3)1−xSx;broadband spectra;photocatalysis
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Electronic Materials
·
2022
·
IF 4.494
Zhang Chen,Xiaotian Sun,Zizheng Wang,Yong Zhu,Chuanxiang Cao,Jiadong Zhou,Yanfeng Gao
Porous carbon was fabricated for broadband microwave absorption application, which was obtained from facile KOH activated carbon microspheres prepared from hydrothermal d-fructose. It is found that micropores (diameter < 2 nm) in the porous carbon played an important role in broadband and high microwave absorption properties. The prepared samples can achieve a wide bandwidth (the widest is 7.9 GHz, from 10.1 to 18 GHz), high dielectric loss (−60.0 dB as the best), and low thickness sensitivity (the bandwidth maintains 70% of the maximum within a film thickness fluctuation of up to 1.02 mm). Our findings offered an invaluable insight into designing and synthesizing highly microwave-absorbing materials through the micro/nanostructure.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
CRYSTENGCOMM
·
2023
·Vol. 25
·期 44
·6162-6170
·
IF 3.1
Shuai Wen,Huan Liu,Lier Deng,Jijie Zhao,Yuxuan Du,Shengyong Wang,Fei Gao,Zhipeng Zhu,Fei Xie,Weiguo Liu
Broadband photodetectors capable of detecting light across a wide spectrum ranging from visible to short wave infrared (SWIR) wavelengths have significant relevance in various fields, including space technology and civil applications. HgTe quantum dots (QDs) have emerged as a promising candidate for the development of low-cost broadband photodetectors. In this study, a photodetector based on a layered structure of indium tin oxide (ITO)/HgTe QD film/gold (Au) was designed and fabricated using a layer-by-layer spin coating method. The fabricated photodetector exhibited a broadband response from 400 nm to 2000 nm, covering the visible and SWIR regions. Its broad spectral range makes it suitable for a wide range of applications. Additionally, the photodetector demonstrated a fast response time of approximately 300 μs, enabling rapid detection and data acquisition. These results highlight the potential of HgTe QDs as a promising material for the development of advanced broadband photodetectors with fast response times. The simplicity of the device structure, combined with the low-cost fabrication technique, makes it an attractive option for commercialization and integration into various optoelectronic systems.
研究领域:
光学工程
·
材料科学
·
电子器件
✓ 已验证
DOI
高影响因子
ADVANCED MATERIALS
·
2024
·Vol. 36
·期 36
·2401733
·
IF 27.4
Xin Wang,Xiaoming Chen,Qingyuan He,Yaozu Hui,Chaofan Xu,Baichuan Wang,Feihu Shan,Jie Zhang,Jinyou Shao
To obtain high-performance electromagnetic microwave (EM) absorption materials with broad effective absorption bandwidth ( EAB ) and reduced thickness, designing structures has proved to be a promising way. Herein, ultra-broadband multilayer bidirectional MXene/polyimide EM absorption aerogels containing multi-structures on scales ranging from the micro- to the macroscale are produced with the aid of electric and temperature fields. On the microscale, under the action of electric force and temperature gradient, the ordered structures made of aligned Ti 3 C 2 T x MXene nanosheets and the microscale layered aerogel walls enable the bidirectional aerogel to achieve a wide EAB of 8.58 GHz at a thickness of 2.1 mm. This is ascribed to the numerous aligned nanosheets and layered aerogel walls perpendicular to the incident EMs, facilitating the conversion of electromagnetic energy into electrical energy. Furthermore, on the macroscale, the multilayer bidirectional aerogel with non-gradient structures effectively resolves the conflict between impedance matching and energy loss, resulting in an ultrawide EAB of 9.41 GHz at a thickness of 3 mm. This innovative design of electric-field-assisted multilayer bidirectional aerogels with multiscale structural coupling may provide feasible and effective pathways for the development of advanced EM absorption materials.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Inorganic Chemistry Frontiers
·
2024
·Vol. 11
·期 23
·8547-8554
·
IF 6.1
Qianyi Chen,Zhenjie Lun,Dongdan Chen,Yongsheng Sun,Puxian Xiong,Siyun Li,Shanhui Xu,Zhongmin Yang
The development of extra-broadband visible emission phosphors is crucial to achieve next-generation illumination with better color experience. Herein, a defect engineering strategy mediated by the structural cationic substitution is proposed and experimentally demonstrated for specific ultra-broadband emission in a garnet phosphor. The induced oxygen vacancies and interstitial cation through lattice distortion break the periodic potential field of the crystal and provide electronic levels in the band gap. As a result, excited by blue-light-emitting diodes, the novel Y3Sc2Al3O12:B3+ shows an ultra-broad emission with a full width at half maximum (FWHM) of ∼170 nm. Compared to general defect-emitting phosphors, the unique Y3Sc2Al3O12:B3+ exhibits excellent thermal quenching resistance and superior internal quantum efficiency of up to 95%. These findings not only show great promise of Y3Sc2Al3O12:B3+ as an extra-broadband emitter but also provide a new design strategy to achieve a full-visible-spectrum phosphor in a single-component material for white-light applications.
研究领域:
材料科学
·
光电技术
·
光子学
✓ 已验证
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2020
·
IF 2.726
Dehai Liang,Xin Lian,Xianli Li,Binbin Luo
Two dimensional (2D) hybrid metal halide perovskites (MHPs) with broadband emission have attracted enormous attention, which is highly promising for single-component solid state lighting. However, it remains a challenge to unveil the underlying origin of broadband emission and achieve high quantum yield (QY). Herein, 2D single-layered [NH 3 (CH 2 ) 4 NH 3 ]CdBr 4 (Cd–P) has been successfully prepared. By partially replacing Cd 2+ with Pb 2+ , the energy band of Cd–P shows a transformation from indirect to direct, supported by the density functional theory (DFT) calculations. Benefiting from the change of energy band, alloyed Cd x Pb 1-x -P shows an intensive broadband emission spanning the whole visible range with a maximum of photoluminescence (PL) QY of 58%. Temperature-dependent and time-resolved PL uncover that the broadband emission origins from the coupling between free excitons (FEs) and [CdBr 6 ] 4- octahedra , instead of [PbBr 6 ] 4- . These findings provide a deep insight into the origin of STEs emission and an effective approach to promote the broadband emission for Cd-based MHPs.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2020
·Vol. 56
·期 3
·2212-2225
·
IF 3.553
Guo Yue,Sun Qiaozhi,Song Kai,Ding Jiawei,Shi Chunsheng,He Fang
With the aim to obtain microwave (MW) absorber possessing simultaneous light weight and broad absorption bandwidth, FeCo imbedded 3D porous carbon network microspheres (3DC@FeCo) were synthesized via spray-drying followed by calcination processes. 3DC@FeCo exhibits 3D porous carbon microspheres structure with submicrometer-sized macropores. The FeCo imbedded carbon structure not only restrains the growth and agglomeration of FeCo nanoparticles, but also effectively introduces polarization and suppresses the skin effect from FeCo. In addition, the 3D porous carbon microspheres provide more channels which enhance the multiple reflection for microwave. The microwave absorption performance of 3DC@FeCo can be adjusted through changing the carbonization temperature, and the sample after carbonized at 630 °C (3DC@FeCo-630) shows the best microwave absorption property. It is worth mentioning that there is only 21.8 wt% FeCo in 3DC@FeCo, indicating that the 3DC@FeCo microspheres proposed in this study are one kind of lightweight microwave absorbers. The minimum reflection loss (RL) value of 3DC@FeCo-630 is − 47.4 dB at 6.35 GHz and the effective absorption bandwidth (RL < − 10 dB) can reach up 5.66 GHz (12.08–17.74 GHz) with the matching thickness of only 2.7 mm. The excellent microwave absorption ability can be attributed to favorable impedance matching, strong dielectric loss, magnetic loss, FeCo imbedded carbon and unique 3D porous structure. 3DC@FeCo microspheres as broadband and lightweight microwave absorbers exhibit a promising prospect applied in complex electromagnetic environments.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2020
·
IF 7.632
Dan Zhao,Shi-Rui Zhang,Yan-Ping Fan,Bao-Zhong Liu,Ya-Nan Li,Lin-Ying Shi,Shao-Jie Dai
Developing broad-band-emitting phosphors is very important to light-emitting diode (LED) lighting and displays. We introduced Eu2+ to solid solutions K2YZr1–yHfy(PO4)3 with a langbeinite-type structure to prepare a series of new phosphors. In this structure, two K+ sites could be occupied by Eu2+ cations to provide two different kinds of coordination environments, leading to broad emitting bands in the range of 390–700 nm. The coordination circumstance of Eu2+ was analyzed by Gaussian fitting and time-resolved emission spectra. Furthermore, the emitting intensity and thermal stability can be improved by modulating the crystalline field via substituting Zr4+ by Hf4+. When the Zr4+ was fully substituted by Hf4+, the external quantum efficiency increased by 53.75%, giving a bright cyan emission. Finally, an archetype white-LED lamp was made using cyan phosphor K2YHf(PO4)3:0.04Eu, red phosphor CaAlSiN3:Eu2+, and a 365 nm LED chip, which realized an applicable color rendering index (Ra = 81) and a correlated color temperature (CCT = 3792 K).
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2021
·Vol. 9
·期 19
·6316-6323
·
IF 7.393
Yuexuan Li,Yugang Duan,Xiaoqing Kang
Microwave absorption materials (MAMs) are specialist kinds of composites applied in stealth technology and electromagnetic interference (EMI). However, it is tough to satisfy the ultrathin and broadband requirements due to the imperfect impedance matching with external air and single absorbing fillers. Herein, a lower concentration of short carbon fiber (SCF)/Prussian blue (PB)/Fe3O4/epoxy resin (EP)-based butterfly-scale metamaterial (BSM) absorber with ultrathin and broadband was achieved via integrated design and fabrication. This revealed that the synergic effect between the SCF/PB/Fe3O4/EP MAMs with dielectric–magnetic behavior and physical resonance loss of the periodic unit for the BSM absorber is profitable for improving the electromagnetic absorption performance. Furthermore, the integrated fabrication process completely avoided the interface effect in traditional metamaterials. As a result, the proposed BSM absorber exhibited an absorption bandwidth of 29.54 GHz below −9.5 dB (>88.7% absorption) under TE = 0° polarization in the 2–40 GHz frequency range and 35 GHz below −9.5 dB under TM = 50° polarization. Analysis of the micro- and macro-absorption mechanism implied that the magnetic loss mainly resulted in power loss compared with dielectric loss. This highlights that the BSM absorber is an appropriate candidate for further practical applications, such as communication devices and military equipment.
研究领域:
材料科学
·
电磁学
✓ 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）