OPTICS AND LASER TECHNOLOGY
·
2023
·
IF 5
Shizhou Tan,Pengcheng Jian,Maocheng Shan,Yongming Zhao,Zhihua Zheng,Yiming Yang,Yuhui Zeng,Dan Xu,Zhenyu Chen,Changqing Chen,Feng Wu,Jiangnan Dai
In this work, we demonstrated tunable structured AlGaN-based nanoporous (NP) distributed Bragg reflectors (DBRs) with high-reflectivity through one-step vertical-lateral electrochemical etching (ECE). The aperture of nanopores in the doping layer and the size and density of V-pits on the surface of NP-DBRs can be tuned by controlling the etching bias. Furthermore, by further tuning the thickness of alternating layers, we achieved high reflectivity of NP-DBRs at multiple center wavelengths within the wavelength range from 280 to 800 nm. To explore its potential applications, MoS 2 with a photoluminescence (PL) emission in the red light region was grown for the first time on the NP-DBRs. Due to the light localized effect of surface V-pits and the high reflectivity of the bottom DBRs , the PL intensity of MoS 2 was significantly enhanced by a factor of 37.3 compared to the region without NP-DBRs. The PL enhancement of MoS 2 on porous AlGaN and different periodic NP-DBRs further validated the PL enhancement mechanism. The corresponding theoretical simulations also revealed that the PL enhancement should be attributed to the combined effect of enhanced light absorption and NP-DBRs induced emission interference. The fabricated AlGaN-based NP-DBRs provide a new approach for improving the quantum efficiency of two-dimensional layered materials, which holds significant importance for advancing the development of miniaturized and integrated 2D/3D heterogeneous structure systems in the field of optoelectronics.
研究领域:
光电子学
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半导体材料
·
纳米光子学
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二维材料
·
固体物理
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表面科学
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集成光子器件
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2018
·Vol. 30
·期 2
·1699-1705
·
IF 2.324
Teng Fei,Chen Dong,Ma Yuzhe,Ji Shaohua,Liu Jiaojiao,Wang Tianhua,Tang Jie,Cao Lifeng,Teng Bing
N,N -dimethylamino-4′-N′-methylstilbazolium 2,4,6-trimethylbenzenesulfonate (DSTMS)-graphene ex-situ and in-situ composite films with 2% concentration of graphene were first prepared and systematically investigated. The crystallinity of DSTMS-based composite films were confirmed by XRD analysis, and the functional groups of composite films can be obtained by FT-IR. Optical absorptions were recorded using UV–Vis-NIR spectral analysis, and the band gap and extinction coefficient of the films were calculated. The thermal stability of the composite films were analyzed by TG/DSC. The pressure sensitive resistance test showed that the pressure sensitive signal of the composite films were significantly increased after graphene added, while the signal of DSTMS film eventually disappears. This work expands the application of organic nonlinear crystal DSTMS in optics and electricity by doping graphene.
研究领域:
材料科学
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凝聚态物理
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功能材料
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非线性光学
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纳米复合材料
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电学性能
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光学性能
·
热分析
✓ 已验证
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2019
·
IF 3.355
Jun Cui,Fanfan Xu,Quan Dong,Junjie Jia,Lili Liu,Shuifu Liu,Fengli Yang,Xinyu Ye
All inorganic cesium lead halide perovskite nanocrystals have attracted widespread attention due to their excellent optical properties. However, large-scale synthesis of high photoluminescence quantum yield (PLQY) CsPbBr 3 nanorods (NRs) is still challenging. Herein, we report a facile, low-cost and large-scale synthesis of CsPbBr 3 NRs with 86 % PLQY at room temperature, in which the employment of acetic acid as precursor solvent promoted the concentrations of Cs + and Pb 2+ in the precursor solution and dominated the formation of CsPbBr 3 NRs. The synthesized CsPbBr 3 NRs with an average width of around 8 nm and average lengths of 18–30 nm have an excellent narrow-band (FWHM = 17 nm) green emission peaked at 517 nm.
研究领域:
材料科学
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纳米技术
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光电子学
·
化学合成
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2024
·
IF 3.3
Jingshan Hou,Jie Shi,Langping Dong,Jianghua Wu,Ganghua Zhang,Haijie Chen,Wei Gao,Yongzheng Fang
The discovery of pure-red emitting phosphor is great meaningful for the achievement of high color rendering index white light emitting diodes , but still a challenge due to the strict crystal field limitations. In this work, we demonstrate the preparation of a 630 nm pure-red emitting Ca 3 Si 2 O 7 :Eu 2+ phosphor for the first time through a CO reduction strategy. The changes in crystal field strength caused by different methods for the preparation of Ca 3 Si 2 O 7 :Eu 2+ are investigated and discussed based on the understanding of the thermodynamic theory and structure resolution. Finally, a white light-emitting diode with a high color rendering index (Ra = 98) is accomplished by combining the as-prepared Ca 3 Si 2 O 7 :Eu 2+ pure-red emitting phosphor with a 375 nm chip and the commercial used blue and green phosphors. The results also demonstrate the generalizability of the weak reduction strategy for the exploration of “redder” Eu 2+ doped phosphors.
研究领域:
材料科学
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光电子学
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固态物理
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无机化学
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照明技术
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2022
·Vol. 46
·期 34
·16273-16279
·
IF 3.925
Haiming Cheng,Chi Cao,Ying Zhang,Dayang Wang,Wensheng Yang,Renguo Xie
Low-dimensional organic–inorganic metal halides have shown great application potential and new opportunities for use in solid-state lighting due to their excellent optical and electronic properties. However, the most studied hybrid compounds contain lead, which limits their application environments. The preparation of organic–inorganic metal halides with high luminous efficiency, long-term stability, and a lead-free composition for environmental protection has become an important goal for the design of materials. Here, novel Sb3+-doped indium-based metal halides, (CH3NH3)4InCl6·Cl, have been designed and synthesized via a simple mechanical ball milling method; in the lead-free zero-dimensional (0D) halide (CH3NH3)4InCl6·Cl, isolated [InCl6]3− octahedra are separated by methylamine cations. Under UV excitation, the bulk-phase powder exhibits broadband orange-yellow emission peaking at 607 nm with a full width at half-maximum of ∼160 nm upon incorporating Sb3+ into the (CH3NH3)4InCl6·Cl matrix. The photoluminescence quantum yield (PLQY) of Sb3+-doped (CH3NH3)4InCl6·Cl is as high as 67.72%. The effects of the Sb3+-doping concentration on the crystal structure and optical characteristic have been investigated. The indirect band gap characteristics of (CH3NH3)4InCl6·Cl were demonstrated via density functional theory (DFT) calculations, and the relatively wide band gaps of 3.83 eV and 2.99 eV of (CH3NH3)4InCl6·Cl and (CH3NH3)4ClInCl6:Sb3+ were experimentally determined. These experimental results suggest that the as-prepared Sb3+-doped (CH3NH3)4InCl6·Cl has potential applications in solid-state lighting devices.
研究领域:
材料科学
·
无机化学
·
光电子学
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固体照明
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半导体材料
✓ 已验证
DOI
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
·
2018
·Vol. 47
·期 4
·2230-2236
·
IF 1.566
Yin Xin,Guan Yingli,Song Lixin,Xie Xueyao,Du Pingfan,Xiong Jie
A bi-layer photoanode is successfully fabricated for dye-sensitized solar cells (DSSCs) composed of P25/TiO 2 nanorod (P25/TNR) as the underlayer and TiO 2 nanosheet spheres (TNSs) as the light-scattering layer. Notably, the P25-TNR provides multiple functions, including more dye loading, more efficient charge transport and a lower electron recombination rate for the photoanode. Besides, the unique structure of TNS can significantly improve the light-harvesting capacity, boosting the light-harvesting efficiency. Therefore, an enhanced short-circuit current and power conversion efficiency of 18.04 mA cm −2 and 5.99%, respectively, were achieved for the P25/TNR-TNS-based DSSC, which was better than that of the P25-TNS-based (15.17 mA cm −2 , 5.36%) and bare TNS-based (11.43 mA cm −2 , 4.14%) DSSCs. This indicates that this bi-layer structure effectively combines the advantages of the one-dimensional (1D) nanostructure and three-dimensional (3D) hierarchical structure. In short, this work demonstrates the possibility of fabricating desirable photoanodes for high-performance DSSCs by rational design of nanostructures and effective combination of multi-functional components.
研究领域:
材料科学
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纳米技术
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能源化学
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光伏器件
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半导体物理
✓ 已验证
DOI
高影响因子
Journal of Macromolecular Science Part A-Pure and Applied Chemistry
·
2024
·
IF 2.1
Long-De Wang,Ling Tong,Jian-Wei Wu,Jie-Wei Rong,Chao Gao,Lu-Lu Bu
Fluorinated polyurethaneimide (PUI) electro-optic waveguide polymer with polyurethane and polyimide chain segment structures was synthesized by stepwise polymerization using the synthesized amino ester oligomer pu and imide oligomer pi as monomers. Since the main chain structure of the synthesized PUI had the functionality of both polyurethane and polyimide chain segment structures, it combines the excellent thermal and film-forming properties of polyurethanes and polyimides, as well as lower optical transmission loss in the near-infrared wavelength band. The glass transition temperature (Tg) of PUI was 182 °C, and the 5% heat loss decomposition temperature was 325 °C. The PUI had good optical properties with an optical propagation loss of 1.10 dB/cm and an electro-optic (EO) coefficient (γ33) of 86 pm/V at a wavelength of 1550 nm. A Mach-Zehnder interferometric polymer waveguide EO modulator had been designed and fabricated by using the PUI as a waveguide electro-optic core layer. The prepared polymer waveguide EO modulator showed a good electro-optic modulation response at a wavelength of 1550 nm under an applied 1 kHz sinusoidal modulation signal. The results showed that the synthesized PUI met the performance requirements for the preparation of polymer optical waveguide devices and was a polymer electro-optic waveguide material with good overall performance.
研究领域:
高分子科学
·
光学材料
·
电光学
·
波导技术
·
聚合物器件制备
✓ 已验证
DOI
高影响因子
Journal of Physical Chemistry Letters
·
2024
·
IF 4.8
Fuyi Zhou,Chang Yi,Jianhong Wu,You Ke,Yuyang Zhang,Nana Wang,Jianpu Wang
Mixing iodide and bromide in three-dimensional metal-halide perovskites is a facile strategy for achieving red light-emitting diodes (LEDs). However, these devices often face challenges such as instability in electroluminescence spectra and low brightness due to phase segregation in mixed-halide perovskites. Here, we demonstrate spectrally stable and bright red perovskite LEDs by substituting some of the halide ions with pseudohalogen thiocyanate ions (SCN–). We find that SCN– can occupy halogen vacancies, thereby releasing microstrain and passivating defects in the perovskite crystals. This leads to the suppression of mixed-halide phase segregation under electrical bias. As a result, the red perovskite LEDs exhibit a high brightness of >35 000 cd m–2 with stable Commission Internationale de l’Eclairage (CIE) coordinates of (0.713, 0.282). This brightness surpasses that of the best-performing red perovskite LEDs, showing great promise for advancing perovskite LEDs in display and lighting applications.
研究领域:
材料科学
·
光电子学
·
固体物理学
·
纳米技术
✓ 已验证
DOI
高影响因子
Laser & Photonics Reviews
·
2024
·Vol. 19
·期 1
·2401012
·
IF 9.8
Pengcheng Jian,Maohua Chen,Dongyan Li,Yongming Zhao,Weijie Liu,Yuang Luo,Xiantai Tian,Meng Peng,Xing Zhou,Jiangnan Dai,Feng Wu,Changqing Chen
The extraordinary mechanical compliance of 2D molybdenum disulfide (MoS 2 ) makes it an ideal candidate for strain modulation of various electrical and optical properties. However, developing facile methods for accurate and stable engineering of strain still remains a major challenge. Here, a novel and effective method is demonstrated for introducing periodic strain into monolayer MoS 2 by direct growth on nano-patterned sapphire substrates (NPSS). A mixed aqueous solution of Na 2 MoO 4 and NaOH is spin-coated on the NPSS and sulfurated in one step by chemical vapor deposition (CVD). Highly oriented monolayer MoS 2 single-crystal nanosheets with high quality and few sulfur vacancies are achieved conformally on the NPSS via a liquid-mediated growth mode. Notably, the periodically distributed blue shift of the PL emission peak demonstrated periodic compressive strain is introduced into the nano-patterned MoS 2 via the thermal expansion difference between MoS 2 and substrates. Furthermore, photodetectors fabricated using the nano-patterned monolayer MoS 2 exhibit a high photo-to-dark current ratio (PDCR) over 10 6 , an excellent detectivity of 5.4 × 10 13 Jones, and a fast photoresponse of 7.7 ms, owing to the strain-induced back-to-back built-in electric field, enhanced light absorption by light-scattering effect and fewer S vacancy defects. The scanning imaging demonstration based on the single-pixel nano-patterned MoS 2 photodetector further confirms its great potential in image sensors. This work hereby presents a pathway for direct conformal growth of nano-patterned monolayer MoS 2 with precisely periodic strain, which should inspire the applications for high-performance optoelectronic devices via the strategy of patterned substrate engineering by the periodic nanostructures.
研究领域:
材料科学
·
纳米科技
·
光电子学
·
凝聚态物理
·
表面科学
·
半导体器件
✓ 已验证
DOI
高影响因子
CHEMISTRY OF MATERIALS
·
2024
·
IF 7.2
Wei Wang,Yi Wei,Lei Qiu,Maxim S. Molokeev,Hang Yang,Huiru Liu,Rui Gao,Mengyu Guan,Dong Tu,Guogang Li
Strong magnetic coupling interactions originating from a short Mn–Mn distance in some heavy Mn2+-doped matrices have important effects on luminescence of single Mn2+ ions and close-knit Mn2+–Mn2+ pairs. However, the intrinsic mechanism of controlling spectral regulation remains elusive since the underlying relationship among Mn–Mn distances, magnetic coupling interactions, and optical properties is unclear. Herein, we create an unusual red emission (620 nm) of Mn2+ in a typical tetra-coordinated lattice of Li2CdGeO4 by simply enhancing the Mn2+-doped level in addition to regular green emission (528 nm). Although the dual emission peaks occupy the same tetra-coordinated crystallographic lattice of CdO4, different temperature-dependent emission behaviors are observed, which expands a possibility in optical thermometry sensors. Detailed Mn–Mn distances are calculated via Rietveld refinement analysis, and their effects on the Mn–Mn coupling interactions are evaluated. Furthermore, the Mn–Mn coupling interaction types are identified through electron spin resonance and magnetic measurements. The continuously decreasing distances between Mn2+ ions strengthen the dipole–dipole coupling effect, resulting in the atypical red emission in a tetra-coordinated lattice environment. These findings elucidate the spectral regulation mechanism from the perspective of magnetic coupling interactions, providing a new pathway to regulate Mn2+-related emission.
研究领域:
材料科学
·
光学
·
固体物理
✓ 已验证
DOI
高影响因子
IEEE SENSORS JOURNAL
·
2023
·Vol. 23
·期 18
·21301-21307
·
IF 4.3
Chuanxin Teng,Yang Liu,Rui Min,Xuehao Hu,Zujun Qin,Hongchang Deng,Libo Yuan
In this article, a reflective surface plasmon resonance (SPR) sensor based on multimode fiber (MMF)–hollow core fiber (HCF) structure is proposed for simultaneous measurement of temperature and humidity. Along the HCF, two different films, i.e., polyvinyl alcohol (PVA) film and polydimethylsiloxane (PDMS) film are coated on the outer surface to generate two SPR resonances at different wavelengths and achieve the simultaneous measurement function. In order to get a better sensing performance, the length ratio of PVA film and PDMS film, and the PVA coating times are optimized. The experimental results show that the humidity sensitivity of the sensor is 0.6351 nm/% relative humidity (RH) in the RH range of 48%–84% RH, and the temperature sensitivity of the sensor is 1.791 nm/°C in the temperature measurement range of 25 °C–80 °C. The sensor has great potential applications in monitoring the environmental temperature and humidity changes.
研究领域:
光学传感
·
材料科学
✓ 已验证
DOI
高影响因子
ACS Sensors
·
2021
·
IF 7.711
Jian Wang,Fangming Chen,Qin Guo,Yao Meng,Mingrui Jiang,Chunsheng Wu,Jian Zhuang,De-Wen Zhang
Here, we describe a new photoelectrochemical imaging method termed light-addressable square wave voltammetry (LASWV). It measures local SWV currents at an unstructured electrolyte/insulator/semiconductor (EIS) field-effect substrate by illuminating and addressing the substrate with an intensity-constant laser. Due to the continuous generation of charge carriers in the light-irradiated semiconductor, the drift and diffusion of photoinjected carriers within the semiconductor bulk would slow down the equilibrium processes of charge and discharge in one potential pulse cycle. Therefore, even though SWV is sampled at the end of the direct and reverse pulses to reject capacitive currents, in our approach, photoinduced capacitive current can still be detected as an effective sensory signal. The obtained current–potential (I–V) curve shows a typical shape corresponding to the accumulation, depletion, and inversion regions of field-effect devices. We demonstrated that LASWV can be used as a field-effect chemical sensor to measure the solution pH and monitor enzymatic reactions. More importantly, since the charge carriers are only generated in the illuminated area, the laser spot in the device can be used as a virtual probe to record local electrochemical properties such as impedance with microresolution.
研究领域:
分析化学
·
生物医学工程
·
电化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）