JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
·
2024
·
IF 2.5
Yingming Zhang,Yujie Yang
Nowadays, the rapid development and demand of electronic products have prompted electronic components to develop towards miniaturisation and even thin film, high integration and modularisation, high performance and ultra-high frequency applications. With the rapid development of electronic information technology and electronic field, NiZn ferrite material as a representative material in the soft magnetic material, through the optimisation of process technology to develop soft magnetic ferrite material with excellent performance is of great practical significance. In this study, Ni 0.3 Zn 0.5 Mg 0.2 Gd x Fe 1.96- x O 4 ( x = 0, 0.02, 0.04, 0.06, 0.08) ferrite materials were prepared by an economical solid phase method. The XRD patterns show that NiZnMgGd ferrite materials can be successfully prepared at low doping content of Gd. However, when x ≥ 0.06, the excess Gd 3+ reacts with Fe 3+ and O 2− in the raw material to produce the heterogeneous phase GdFeO 3 . From the SEM images, it can be seen that the higher the Gd content, the higher the number of small grains in the sample. A small amount of Gd 3+ doping has a contributing effect on reducing the P cv of ferrite. The quality factor of the ferrite sample with x = 0.02 is 11.92 when the frequency is 1000 kHz, which is an improvement of 100.67 % compared to the ferrite without Gd doping. From the M−H curves, M s decreases with the increasing content of Gd replacing Fe, and NiZnMgGd ferrite is more likely to reach saturation under the action of external magnetic field. M s , M r and H c indicate that NiZnMgGd ferrite material has typical soft magnetic properties.
研究领域:
材料科学
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电子材料
·
磁学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Tianyun Du,Xiaojie Xue,Xiuxun Han
Rare earth activated color converted phosphors have been widely used in solid-state lighting and display fields. Developing phosphors with high luminous efficiency is of great significance for light-emitting devices. Concentration quenching is the main factor limiting the improvement of phosphor luminescence efficiency during increasing the activator doping level. In this study, a novel structural optimization strategy is developed to overcome the impact of concentration quenching. In Tb 3+ activated NaYSiO 4 (NYSO), large-size Gd 3+ ions are introduced to adjust the distance of rare earth ions and suppress the energy transfer between Tb 3+ luminescent centers. It is shown that at a critical Tb 3+ concentration, for which concentration quenching tends to occur in NaYSiO 4 :Tb 3+ , Gd 3+ incorporation successfully raises the internal quantum efficiency from 64.8 % for Tb 3+ -singly-doped NYSO up to 80.6 % for Gd 3+ /Tb 3+ co-doped one. The findings can offer a feasible pathway in promoting the luminescent properties of silicate phosphor hosts.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
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
JOURNAL OF RARE EARTHS
·
2017
·
IF 2.429
Caiyan YU,Tongtong XUAN,Sunqi LOU,Xiaoxiao LIU,Guohai LIAN,Huili LI
Recently, CuInS 2 /ZnS nanocrystals (CISZ NCs) have been widely used in many fields due to their excellent properties, such as tunable photoluminescence (PL) spectra, broad absorption, and non-toxicity. In order to expand the application of CISZ NCs, Gd 3+ was introduced into the host serving as paramagnetic modules to achieve magnetic resonance imaging (MRI) enhancement. MRI probes could provide high-resolution anatomical information. The derived Gd-Cu-In-S/ZnS nanocrystals (GCISZNCs) exhibited the strong orange photoluminescence with a quantum yield of 57.6% and significantly high longitudinal relaxivity ( r 1 =20.4 mmol/s) in comparison with commercial Magnevist (Gd-DTPA, r 1 =4.5 mmol/s). Effective enhancement of MRI and improved longitudinal relaxivity as well as lower cytotoxicity mode GCISZ NCs an ideal MRI probe, suggesting its potential and significance in practical biological and clinic applications in the future.
研究领域:
生物医学工程
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材料科学
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医学影像学
✓ 已验证
产品关联
DOI
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2021
·
IF 4.098
Jiacheng Gong,Wenqin Luo,Weirong Lan,Xi Chen,Haiyan Wu
Sr 3 LiSbO 6 phosphors were prepared by high temperature solid state reaction method. The crystal phase, morphology and optical properties were characterized by X-ray powder diffraction spectroscopy, scanning electronic microscope, absorption and photoluminescence (PL) spectra. The XRD Rietveld refinement was performed to obtain the detailed crystal structure of Sr 3 LiSbO 6 . The electronic structure was analyzed by density functional theory (DFT) calculation. Sr 3 LiSbO 6 possessed indirect band structure and the band-gap were determined to be 3.17 eV. Self-activated far-red emissions at 630–800 nm were detected under the excitation at 340 nm, which was proposed to originate from the transition between interstitial oxygen defective state to six hybrid 4d 10 5s 0 states of Sb 5+ according to the results of PL spectra of samples annealed at different atmospheres. The PL intensity can be significantly enhanced by 2.9 times after doping 2 mol% Gd 3+ ions in Sr 3 LiSbO 6 . The internal quantum efficiency of Sr 3 LiSbO 6 :2 mol%Gd 3+ was determined to be 25.2%. The influence of the Gd 3+ doping on the self-activated PL lifetimes of Sr 3 LiSbO 6 and the thermal quenching property of Sr 3 LiSbO 6 :2 mol%Gd 3+ was studied.
研究领域:
材料科学
·
光学
·
植物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Photonics Research
·
2021
·Vol. 9
·期 10
·1916-1923
·
IF 7.08
Qingyun He,Enrou Mei,Ze Wang,Xiaojuan Liang,Xiaojuan Liang,Suqin Chen,Suqin Chen,Weidong Xiang
Here, Gd-doped CsPbCl1.5Br1.5 nanocrystals (NCs) in borosilicate glass matrix (B2O3−SiO2−ZnO) were prepared by melting quenching and in-situ crystallization. The optical performance of CsPbCl1.5Br1.5 NCs glasses under different heat-treatment temperatures and the content of Gd3+ were analyzed in detail. After CsPbCl1.5Br1.5 NCs glass is doped with Gd3+ ions, the photoluminescence intensity increases and the synthesized Gd-doped CsPbCl1.5Br1.5 NCs glasses have excellent water stability and thermal cycling performance. In addition, the influence of Gd-doped concentrations and heat-treatment temperatures on the amplified spontaneous emission (ASE) thresholds of CsPbCl1.5Br1.5 NCs glasses was studied, and the Gd-doped CsPbCl1.5Br1.5 NCs glasses achieve controllable ASE thresholds at room temperature. The ASE threshold can be as low as 0.39 mJ/cm2. This work offers a neoteric reference for the research in the application of metal ion-doped perovskite NCs and a new idea for the realization of controllable and low ASE thresholds on perovskite NCs.
研究领域:
材料科学
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光学工程
✓ 已验证
产品关联
DOI
高影响因子
MOLECULES
·
2025
·Vol. 30
·期 5
·1085
·
IF 4.6
Dong Zhu,Chunfeng Wang,Xiaohuai Wang,Shun Han,Yuxiang Zeng,Ming Fang,Wenjun Liu,Deliang Zhu,Peijiang Cao,Youming Lu
The co-precipitation method was successfully used to synthesize Ba3(Y0.6−xGd0.4Eux)4O9(0.01 ≤ x ≤ 0.09) phosphors with heavy Gd3+doping, resulting in significantly enhanced thermal stability and luminescence performance. Structural analyses confirm that Gd3+and Eu3+ions substitute Y3+in the lattice, causing lattice expansion and improving crystal asymmetry, which enhances Eu3+emission. The incorporation of Gd3+creates efficient energy transfer pathways to Eu3+while suppressing non-radiative relaxation, leading to stable fluorescence lifetimes even at elevated temperatures. With a thermal activation energy of ~0.3051 eV, the Ba3(Y0.55Gd0.4Eu0.05)4O9phosphor exhibits superior resistance to thermal quenching compared to Ba3(Y0.95Eu0.05)4O9and many conventional red phosphors. Furthermore, the reduced color temperature and stable emission spectra across a wide temperature range highlight its potential for advanced lighting and display technologies in high-temperature environments.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
OPTICAL MATERIALS
·
2020
·
IF 2.779
Hua Li,Xiaobo Shi,Xia Li,Lingbo Zong
Size-tunable β-NaYF 4 : Yb/Er (50–400 nm) up-converting nanoparticles (UCNPs) with a strong green emission were successfully prepared by a facile thermal decomposition method in a short period of time. The effects of the reaction time, the oleic acid (OA) content, and the doped Gd 3+ concentration on the crystal structure, the size evolution mechanism and the luminescence mechanism of the β-NaYF 4 : Yb/Er nanoparticles were discussed in detail. Characterization was completed using X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution (HR-TEM), scanning electron microscopy (SEM), and photoluminescence (PL). The results reveal that the phase transition was completed at 15 min and the morphology of the NaYF 4 : Yb/Er UCNPs changed from spherical to large hexagonal disks (200–400 nm) in non-doped Gd 3+ . An appropriate decrease in the volume ratio of oleic acid (OA) to 1-octadecene (ODE) promoted NaF production, resulting in the formation of the hexagonal phase crystals and the subsequent increase of luminous intensity by 30–40 times. More importantly, the size of the β-NaYF 4 : Yb/Er decreased with Gd 3+ doping, and the UCNPs ultimately transformed into small hexagonal prisms (50 nm) with high monodispersity when the doping concentration of Gd 3+ was 60 mmoL. The PL spectra confirmed that the luminous intensity of the UCNPs with doped Gd 3+ was much higher than that of the undoped UCNPs. The results show that this route for UCNP fabrication with high luminous efficiency and a small size could be extended to other UCNP systems for multifunctional biomedical applications.
研究领域:
材料科学
·
光学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Qingyun He,Yaqian Zhang,Yanxia Yu,Ya Chen,Mengfeifei Jin,Enrou Mei,Xiaojuan Liang,Lanlan Zhai,Weidong Xiang
Here, Gd-doped CsPbBrI 2 nanocrystals (NCs) in borosilicate glass (B 2 O 3 -SiO 2 -ZnO) were successfully synthesized by the traditional melting quenching method. The optical properties of CsPbBrI 2 NCs@glasses at different heat treatment temperatures and the content of Gd 3+ were studied. It is found that CsPbBrI 2 NCs@glasses have greatly improved photoluminescence quantum yields (PLQYs) after doping (form 15.3% to 37%) and excellent hydrothermal and light stability. In addition, a white light emitting diode (WLED) was successfully prepared by combining Gd-doped CsPbBrI 2 NCs@glass and Ce 3+ : YAG phosphors with the blue light emitting diode (LED). After a series of adjustments, the high performance WLED device with a chromaticity coordinate (CIE) of (0.3340, 0.3386), luminous efficiency (LE) of 90.09 lm/W, correlated color temperature (CCT) of 5430 K and the color rendering index (CRI) of 81.4 was fabricated. This work provides a new strategy in the field of metal ion doped perovskite NCs for future reference and has potential applications in LEDs.
研究领域:
材料科学
·
光学工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2021
·Vol. 33
·期 31
·23880-23887
·
IF 2.478
Ding Yanli,Zhang Xiaodan,Zhao Ying
The use of upconversion (UC) materials is an effective strategy for harvesting the near-infrared (NIR) solar photons in perovskite solar cells. Hexagonal β-NaLuF 4 :Yb,Er submicron prisms were synthesized by a facile solvothermal method. Gd 3+ doping is used to enhance the UC emission intensity. We investigated how the concentration of Gd 3+ ions affected the morphological evolution, microstructure, and luminescence performance of NaLuF 4 :Yb,Er and explored the mechanism for improving luminescence at 980 nm excitation. By incorporating the optimized NaLuF 4 :Yb,Er,Gd into the perovskite solar cells’ (PSCs) hole transport layer, the short-circuit density ( J sc ) of UC-PSCs can be enhanced from 19.31 to 21.77 mA cm −2 .
研究领域:
材料科学
·
光学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
OPTICAL MATERIALS
·
2025
·
IF 4.2
Feihong Yang,Weiwei Li,Peng Luo,Jing Cheng,Laiming Chen
Transparent Yb:CaF 2 ceramics have recently emerged as a promising ultra-fast laser medium with broad emission bandwidth, long lifetime and suitable thermal properties. However, Yb 3+ clustering in the CaF 2 host strongly influences the performance of these materials as solid-state laser gain media, and mitigating this clustering remains a challenge. Herein, we introduced Y 3+ and Gd 3+ buffer ions simultaneously for the first time to modulate the fluorescence properties of transparent Yb:CaF 2 ceramics and explore the effect of Y 3+ and Gd 3+ ions co-doping on the optical quality and microstructure of the ceramics. It was found that transmittance in the short wavelength was improved and fluorescence properties could be modulated to a larger extent compared to single buffer ion doping. This finding establishes the correlation between the double buffer ions doping and the fluorescence properties in transparent Yb:CaF 2 ceramics, and may lead to innovative techniques of transmitting enhancement, as well as its ultrafast laser applications.
研究领域:
材料科学
·
光学材料
·
固体激光器
·
陶瓷材料
·
光谱学
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Communications
·
2022
·
IF 3.662
Yuhong Zhang,Nan Zhang,Pengcheng Wang,Xingke Zheng,Yibin Guo,Hang Liu
In this work, tungstate BaWO 4 phosphors doped Ho 3+ -Yb 3+ -Gd 3+ ions are successfully synthesized through solid-state reaction method. Under the excitation of a 980 nm laser, the up-conversion (UC) luminescence properties are investigated simultaneously. The blue (465 nm, 489 nm), green (541 nm) and red (665 nm) emission intensities of BaWO 4 : Ho 3+ /Yb 3+ /Gd 3+ samples are dramatically enhanced by 20.59, 9.83, 7.37, and 27.59 times more than those without Gd 3+ ions. The possible reason is discussed, which attributes to the energy transfer efficiency enhancement from Yb 3+ to Ho 3+ due to the lattice expansion induced by Gd 3+ ions. The temperature-sensing properties of BaWO 4 : Ho 3+ /Yb 3+ /Gd 3+ samples are also discussed based on the fluorescence intensity ratio (FIR) technology. The sensitivity of temperature measurement for BaWO 4 : Ho 3+ /Yb 3+ /Gd 3+ sample is higher than that of BaWO 4 : Ho 3+ /Yb 3+ . It proves that the codoped Gd 3+ ions can also increase the temperature sensitivity because the higher UC emission efficiency will lead to a high signal-to-noise ratio. The result provides an effective way to design UC luminescence materials with high temperature sensing properties.
研究领域:
材料科学
·
光学材料
·
发光学
·
传感器技术
·
无机功能材料
✓ 已验证
DOI
高影响因子