ULTRASONICS SONOCHEMISTRY
·
2016
·
IF 4.556
Guanshu Li,Hongbo Zhang,Chunsheng Wei,Yingying Huang,Xuekai Dou,Yidi Wang,Jun Wang,Youtao Song
(5.0%)Er 3+ :Y 3 Al 5 O 12 /Pt-(TiO 2 -Ta 2 O 5 ) powder, as a high effective sonocatalyst, was prepared using sol-gel and calcination method. Then it was characterized by X-ray diffractometer (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDX). In order to evaluate the sonocatalytic activity of the prepared (5.0%)Er 3+ :Y 3 Al 5 O 12 /Pt-(TiO 2 -Ta 2 O 5 ) powder, the sonocatalytic decomposition of ametryn was studied. In addition, some influencing factors such as different Ti/Ta molar ratios on the sonocatalytic activity of the prepared (5.0%)Er 3+ :Y 3 Al 5 O 12 /Pt-(TiO 2 -Ta 2 O 5 ) powder, catalyst added amount with ultrasonic irradiation time and used times on the sonocatalytic decomposition efficiency were examined by using ion chromatogram determination. The experimental results showed that the best sonocatalytic decomposition ratio of ametryn were 77.50% based on the N atom calculation and 95.00% based on the S atom calculation, respectively, when the conditions of 10.00 mg/L initial concentration, 1.00 g/L prepared (5.0%)Er 3+ :Y 3 Al 5 O 12 /Pt-(TiO 2 -Ta 2 O 5 ) powder (Ti/Ta = 1.00:0.25 heat-treated at 550 °C for 3.0 h) added amount, 150 min ultrasonic irradiation (40 kHz frequency and 300 W output power), 100 mL total volume and 25–28 °C temperature were adopted. Therefore, the (5.0%)Er 3+ :Y 3 Al 5 O 12 /Pt-(TiO 2 -Ta 2 O 5 ) composite nanoparticles could be considered as an effective sonocatalyst for decomposition of ametryn in aqueous solution.
研究领域:
材料科学
·
环境科学
·
化学工程
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2025
·Vol. 108
·期 9
·e20684
·
IF 3.8
Yuanyuan Li,Hongbing Yang,Yilei Huang,Shichang Cheng,Chang-An Wang,Yanhao Dong
The exploration of sintering dynamics in systems involving oxide nanoparticles is vital for the production of nanocrystalline oxide ceramics. Until now, a thorough investigation into the sintering kinetics of well-dispersed, fine-grained yttrium aluminum garnet yttrium aluminum garnet (Y 3 Al 5 O 12 ; YAG) nanoparticles has been lacking. In this study, we delve into the sintering kinetics of uniformly dispersed, equiaxed YAG nanoparticles, which possess an average diameter of 9 nm and span a size range from 3 to 39 nm. We have successfully fabricated dense YAG ceramics with an average grain size of 86 nm through a pressureless sintering process in air atmosphere at a mere 1200°C for a duration of 2 h. This sintering temperature marks the lowest recorded for the pressureless sintering of YAG ceramics. The resulting nearly fully dense YAG nanocrystalline ceramics showcase the finest grain size achieved to date via pressureless sintering techniques, aligning with our efforts to refine grain size and reduce sintering temperatures in advanced ceramic materials.
研究领域:
材料科学
·
陶瓷
·
纳米技术
·
烧结动力学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL PHYSICS LETTERS
·
2021
·
IF 2.328
Jiazhi Li,Zhidong Ma,Fu Wang,Zhaofeng Wang
In this work, submicro-sized Y 3 Al 5 O 12 :Ce 3+ particles were synthesized via a coprecipitation method. When mechanical stimuli are applied, the submicro-sized Y 3 Al 5 O 12 :Ce 3+ can exhibit intense greenish-yellow mechanoluminescence. Different from the bulk Y 3 Al 5 O 12 :Ce 3+ synthesized by conventional solid-state method, the mechanoluminescence of the submicro-sized Y 3 Al 5 O 12 :Ce 3+ exhibits a trap-dependent behavior. The distinct spectral characteristics between photoluminescence and mechanoluminescence further suggest that distorted Ce 3+ sites could be generated under mechanical stimuli, and therefore the mechanoluminescent mechanisms of the submicro-sized Y 3 Al 5 O 12 :Ce 3+ are revealed.
研究领域:
材料科学
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发光材料
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力致发光
·
纳米材料合成
✓ 已验证
DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2013
·
IF 2.56
Xiangbo Ji,Jianguo Deng,Bin Kang,Hui Huang,Xin Wang,Wei Jing,Tao Xu
Yttrium aluminum garnet (YAG) nano-precursors were synthesized by urea homogeneous co-precipitation. The morphology and crystalline phase, particularly the in situ evolved gases of as-synthesized precursors during the thermal decomposition, were characterized and verified. The evolved NH 3 , H 2 O, and CO 2 gases can be observed below 600 °C. The released NO 2 gas was observed at 202 °C, 500 °C and 885 °C, which suggests that N O 3 − existed in the precursor with three different forms. Furthermore, the evolved SO 2 gas was detected above 850 °C due to desulfurization. Phase-pure YAG can be obtained when the precursor was calcined at 900 °C. The particle size increases with increasing calcination temperature. The powders calcined at 1100 °C were well dispersed and had an average grain size of 100 nm owing to the decomposition of S O 4 2 − at high temperatures.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Jian Li,Jia Liu,Yeqing He,Xiaohan Zhang,Yanxiang Jiang,Yang Wang,Wei Sun,Yuanyuan Zhou,Walther Glaubitt,Futian Liu,Haitao Wu,Fei Wang,Ling Li
High-performance dielectric ceramics are vital for next-generation microwave devices, requiring advanced doping and composite strategies to enhance material properties. The (1- x )MgAl 2 O 4 - x Y 3 Al 5 O 12 composite ceramics were found in the MgO-Al 2 O 3 -Y 2 O 3 pseudoternary phase diagram and synthesized via solid-phase reaction. The two phases coexist to improve grain size distribution and achieve a low eutectic temperature, allowing x = 0.1–0.7 samples to gain a dense microstructure ( ρ > 96 %) when sintered at 1650–1670 °C. The semi-coherent interface, coupled with the Mg 2+ /Y 3+ cation transition zone, promotes the formation of a partial solid solution, thereby alleviating interfacial stress at the grain boundaries between MgAl 2 O 4 and Y 3 Al 5 O 12 . Notably, the 0.3MgAl 2 O 4 -0.7Y 3 Al 5 O 12 ceramic exhibits satisfying microwave dielectric properties: ε r = 10.1 ± 0.24, Q × f = 195,000 ± 12,000 GHz, and τ f = −11.9 ppm/°C. In addition to phase composition and microstructure, the enhanced performance can be attributed to the optimized crystal structure. The partial substitution of Y 3+ by Mg 2+ with a smaller radius induced the “rattling” effect and abnormal large permittivity in the [YO 8 ] site. The 27 Al NMR spectra revealed an increase in the Mg-Al inversion degree in the Mg-deficient spinel structure, resulting in the elevated total covalency of the Al-O bond. The structural changes corresponded to a decrease in intrinsic dielectric loss in Mg-Al spinel and an increase in τ f in the Y-Al garnet phase. These findings indicate the (1- x )MgAl 2 O 4 - x Y 3 Al 5 O 12 ceramics have promising applications in the field of HTCC millimeter wave communications.
研究领域:
材料科学
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电子工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2018
·Vol. 53
·期 21
·15196-15203
·
IF 2.993
Song Li,Dong Yan,Shao Qiyue,Jiang Jianqing
Nano-yttrium aluminum garnet (YAG) is a promising material for use in white light-emitting diodes and biological fluorescent probe. However, its existing preparation methods often suffer from low synthesis temperature and particle agglomeration. Therefore, preparing YAG nanoparticles with both high crystallinity and high dispersibility is difficult, which severely limits the applications of nano-YAG phosphor. This work presents a salt microemulsion method that can yield YAG nanoparticles of size 4–6 nm that are dispersed at a high temperature (1000 °C). Transmission electron microscope analysis shows that the precursor particles are dispersed and isolated by nano-sized potassium sulfate particles. Because the melting point of potassium sulfate is high (1067 °C), the precursors and the YAG nanoparticles are always dispersed and isolated by the solid potassium sulfate salt during calcination at high temperatures, resulting in the formation of dispersed YAG nanoparticles with good crystallinity. The reflection spectrum of nano-YAG exhibited a redshift compared to that of bulk YAG. When the Ce content is 0.06, the nano-YAG phosphor exhibited the highest internal photoluminescence quantum yield of 51.2%, and the decrease in the particle size did not increase the quenching concentration. The nano-YAG prepared at a high temperature also exhibited improved optical stability: The luminescence intensity of the nano-YAG decreased by only~ 16% after 48 h of irradiation using blue laser. The obtained 4–6-nm-sized Y 3 Al 5 O 12 :Ce nanophosphors are expected to be ideal materials for novel fluorescent probes and preparation of transparent ceramics.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2021
·Vol. 104
·期 9
·4659-4668
·
IF 3.784
Chao Du,Mao-Sen Fu,Di Zhou,Huan-Huan Guo,He-Tuo Chen,Jian Zhang,Jun-Ping Wang,Shao-Fei Wang,Hai-Wen Liu,Wen-Feng Liu,Long Li,Zhuo Xu
Microwave dielectric ceramics are considered to be one of the key materials for dielectric resonators (DR) and have very broad application prospects in the fifth generation (5G) mobile communication system. Here we have prepared high-quality factor Y 3 Al 5 O 12 (YAG) transparent dielectric ceramics using high-purity α-Al 2 O 3 and Y 2 O 3 powders by cold isostatic pressing of the vacuum sintered with tungsten meshes as the heating elements. Optimum relative permittivity ( ) ~10.53, quality factor Q × f (Q = 1/dielectric loss, f = resonant frequency) ~95, 270 GHz (at =7.37 GHz), and temperature coefficient of resonant frequency (TCF) ~ −51.7 ppm °C −1 were obtained at a sintering temperature of 1780°C for 12 h. For the first time, YAG transparent ceramic dielectric resonator antenna (DRA) is designed as a dominant mode and a higher-order mode using the aperture coupling feeding configuration excitation. The proposed transparent dielectric ceramic DRA can provide a broad impedance bandwidth of 4.193 GHz (ranging from 21.90 to 26.09 GHz) for S 11 < −10 dB, radiation efficiency of 92.1%, and compact DR unit. The proposed DRA can be used potentially as a 5G millimeter (mm)-wave multiple-input-multiple-output (MIMO) antenna unit.
研究领域:
材料科学
·
通信工程
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Moke Zhou,Hetuo Chen,Guohong Zhou,Yi He,Shuren Zhang,Bin Tang
Four control experiments (S1: Y 3 Al 5 O 12 , S2: Y 3 Al 5 O 12 +1 wt%Nb 2 O 5 , S3: Y 3 Al 4.955 Nb 0.045 O 12 , S4: Y 2.955 Al 5 Nb 0.045 O 12 ) were designed to investigate the co-effects of Nb 2 O 5 and non-stoichiometry on the microwave dielectric properties of Y 3 Al 5 O 12 . The beneficial results of Nb 2 O 5 doping are demonstrated based on X-ray patterns, electron diffraction information, Rietveld refinement , and micromorphological characterization. Differences in dielectric properties were explored using lattice defects, ion polarizability, bond valence, and Raman spectroscopy . In contrast, the Y-deficient sample (S4) possesses the best dielectric properties ( ε r ∼ 10.37, Q × f ∼ 161,724 GHz and τ f ∼ -33.8 ppm/°C).
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2017
·
IF 3.582
Ying Zhou,Shengnan Wei,Siyi Li,Xudong Liu,Xiaoqing Shu,Xu Zhang,Cheng Zhao,Zepeng Qu,Dawei Fang,Zhaohong Zhang,Jun Wang
By using TiO 2 and Ta 2 O 5 colloids, a stable and efficient visible-light driven photocatalyst , Er 3+ :Y 3 Al 5 O 12 /TiO 2 Ta 2 O 5 /MoO 2 composite membrane , was successfully prepared via sol–gel dip coating method at room temperature . The XRD , FTIR, SEM , TEM and EDX results confirm that approximately spherical Er 3+ :Y 3 Al 5 O 12 nanoparticles were embedded in TiO 2 Ta 2 O 5 matrix. UV–vis absorption and PL spectra of Er 3+ :Y 3 Al 5 O 12 were also determined to confirm the visible absorption and ultraviolet emission. The photocatalytic hydrogen generation was carried out by using methanol as sacrificial reagent in aqueous solution under visible-light irradiation. Furthermore, some main influence factors such as heat-treated temperature, heat-treated time and molar ratio of TiO 2 and Ta 2 O 5 on visible-light photocatalytic hydrogen generation activity of Er 3+ :Y 3 Al 5 O 12 /TiO 2 Ta 2 O 5 /MoO 2 composite membrane were studied in detail. The experimental results showed that the photocatalytic hydrogen generation activity of Er 3+ :Y 3 Al 5 O 12 /TiO 2 Ta 2 O 5 /MoO 2 composite membrane heat-treated at 550 °C for 3.0 h was highest when the molar ratio of TiO 2 and Ta 2 O 5 was adopted as 1.00:0.50. And that a high level photocatalytic activity can be still maintained after four cycles. In addition, a possible mechanism for the visible-light photocatalytic hydrogen generation of the Er 3+ :Y 3 Al 5 O 12 /TiO 2 Ta 2 O 5 /MoO 2 membrane was proposed based on PL spectra.
研究领域:
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
·
2026
·
IF 4.6
Qinghong Meng,Yuning Zhang,Xiangming Li,Wanjun Yu,Yaping Wang,Zhijun Xu,Ji-Guang Li
To modulate the structure and optical properties of Cr3+-activated Y3Al5O12 garnet with typical narrowband near-infrared (NIR) emitting, cation substitution was implemented to establish novel Y3–xCaxAl5–xSnxO12:yCr3+ broadband NIR phosphors in this work. Density functional theory calculations, Rietveld refinement, X-ray photoelectron spectroscopy, and UV–vis–NIR/photoluminescence spectroscopy analysis clearly elucidated that the equimolar Ca2+ and Sn4+ doping led to the expansion of the lattice and the enhanced distortion degree of the [(Al,Sn,Cr)O6] octahedron. They thus resulted in a reduction in the crystal-field magnitude and in a massive redshift and spectral broadening of the emission band. The optimal x = 1.5/y = 0.06 phosphor manifested wide-band NIR emission with a center at ∼764 nm and a full width at half-maximum of ∼135 nm, a high luminous efficiency (internal quantum efficiency = 75.6% and external quantum efficiency = 25.1%), and favorable thermal stability (74.5% at 423 K). The manufactured pc-NIR-LED device using this optimal phosphor exhibited satisfactory NIR output power (∼21.1 mW) and efficiency (8.53%), signifying that this garnet phosphor has potential for application in the construction of pc-NIR-LEDs for night vision, noninvasive medical diagnosis, and nondestructive detection.
✓ 已验证
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2016
·
IF 3.205
Yahui Song,Shengnan Wei,Yang Rong,Chunxiao Lu,Yang Chen,Jun Wang,Zhaohong Zhang
Several conduction band co-catalysts (CBCOs), MoO 2 , MoS 2 and MoSe 2 , were prepared to improve the visible-light photocatalytic hydrogen evolution activity of Er 3+ :Y 3 Al 5 O 12 /PdS–ZnS from water splitting, in which the PdS is a valence band co-catalyst (VBCO) used to facilitate the photo-generated hole transfer and the Er 3+ :Y 3 Al 5 O 12 is an up-conversion luminescence agent from visible light to ultraviolet light used to provide the ultraviolet light satisfying the energy demands of wide band-gap ZnS photocatalyst . XRD , SEM, TEM and EDX analyses were employed to confirm the morphology, microstructure and composition of the prepared photocatalysts. UV–vis absorption and PL spectra were also determined to explore luminescence effect of the Er 3+ :Y 3 Al 5 O 12 . The visible-light photocatalytic hydrogen evolution activity of the prepared photocatalysts was evaluated by using Na 2 S and Na 2 SO 3 as sacrificial reagents in aqueous solution under visible light irradiation . The influential factors such as contents of CBCOs (MoO 2 , MoS 2 and MoSe 2 ) and visible-light irradiation time on visible-light photocatalytic hydrogen evolution of Er 3+ :Y 3 Al 5 O 12 /PdS–ZnS–MoX 2 (X = O, S and Se) were investigated in detail. Particularly, Er 3+ :Y 3 Al 5 O 12 /PdS–ZnS–MoSe 2 with 0.30 wt% MoSe 2 shows the highest photocatalytic hydrogen evolution activity.
研究领域:
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
OPTICAL MATERIALS
·
2025
·
IF 4.2
Bingguo Liu,Yanghan Guo,Yangzi Li,Shiqing Pang,Shunzi Li,Peng Xu,Dan Zhao,Carsten Dam-Hansen,Jian Xu,Baoli Du,Ole Bjarlin Jensen
Phosphor-in-glass film (PiG-film) displays great potential for high performance laser-driven white lighting, benefiting from its facile fabrication and high efficiency. However, the low thermal conductivity of the glass matrix may lead to thermal quenching of phosphors and limit the maximum luminous flux of the light source . Here, boron nitride (BN) with high thermal conductivity and low absorption coefficient was embedded into Y 3 Al 5 O 12 :Ce PiG-film to facilitate the heat-transfer process, and to regulate the propagation of both laser and fluorescence. The influences of BN particle size and doping concentration on surface morphology (pore formation), luminescence saturation threshold (LST), luminous flux, and the spatial distribution of correlated color temperature (CCT) were investigated and correlated. Moreover, the luminescence spot confinement was analyzed and luminous exitance was obtained. Benefiting from the formation of effective BN heat-transfer network, the luminous efficacy of both YAG-45-2 % and YAG-45-1 % films surpass the non-doped one as laser power density >19.00 W/mm 2 . A LST higher than 27.04 W/mm 2 was observed in YAG-45-2 % film, more than 42 % higher than the non-doped one. Though the extra reflection of blue laser by BN particles downgrades the CCT spatial distribution uniformity, the particles strongly scatter the fluorescence and restrict the fluorescence-emitting spot (diameter) expansion from 307 to 174 μm, and a high luminous exitance of 1614 lm/mm 2 was achieved in YAG-45-2 % film. These results firmly demonstrate that incorporation of particles with high thermal conductivity and low absorption coefficient in PiG-film is a feasible strategy for achieving high-brightness laser lighting.
研究领域:
材料科学
·
光学工程
·
固态照明
·
热管理
·
光子学
✓ 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）