JOURNAL OF LUMINESCENCE
·
2024
·
IF 3.3
Yaping You,Ya Zheng,Zesheng Pan,Yunluo Wang,Tianrui Zhou,Minghui Wang,Haijie Chen,Wan Jiang,Lianjun Wang
White light-emitting diode (WLED) has been widely used as solid-state lighting in recent years, with the advantages of energy saving, high luminous efficiency , and safety. Red phosphors are crucial to the color rendering index of WLED, and Eu 3+ -activated red phosphors can significantly improve the chromaticity performance of WLED. In this work, a series of new orange-red emitting BaLiZn 3 (PO 4 ) 3 : Eu 3+ phosphors were synthesized through high-temperature solid-state reaction method. The phase composition , crystal structure, morphology and photoluminescence properties of BaLiZn 3 (PO 4 ) 3 : Eu 3+ samples were investigated. The phosphors can be effectively excited by the violet light at 394 nm and emit orange-red lights corresponding to the electric dipole transition (5D 0 →7F 1 ) at 594 nm. The optimal doping concentration of Eu 3+ ions was about 5 mol%. The concentration quenching was caused by the electric dipole-dipole interaction between Eu 3+ ions. Temperature-dependent PL spectra indicate that BaLiZn 3 (PO 4 ) 3 : Eu 3+ has excellent emission and color stability at high temperatures. The color coordinates were calculated and fall in the orange-red luminescent area. The color purity is about 98.3 %, and the correlated color temperature is 1710K. These results indicate that the new orange-red phosphor BaLiZn 3 (PO 4 ) 3 : Eu 3+ has potential application prospects in WLED.
研究领域:
材料科学
·
发光材料
·
固体照明
·
无机化学
·
光电子学
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2020
·
IF 3.28
Zhiqin Zheng,Peizhang Xie,Panpan Yi,Jun Zhao,Lihong Liu,Facheng Yi
Nowadays, ultraviolet (UV) and blue converted phosphors have played a key role in the solid-state lighting field, and the white light is usually produced by mixing multiple phosphors. In this work, we report a type of UV converted single white phosphor, i.e. , Ba 9 La 2 Si 6 O 24 :Eu 3+ ,Bi 3+ .Various techniques, such as powder X-ray diffraction (XRD), scanning electron microscopic (SEM), photoluminescence (PL) spectra, and quantum efficiency (QE), have been used to characterize the samples. In Bi 3+ doped samples, upon excitation within the wavelength range of 250–380 nm can lead to three Bi 3+ emission bands ( i.e. , 358 nm, 415 nm, and 516 nm), but only one emission band peaking at 415 nm appears when the excitation wavelength exceeds 380 nm. Structural analysis and discussion on the PL intensity variation reveal there are three Bi 3+ luminescent centers at two different La 3+ sites and one Ba 2+ site. The Bi 3+ concentration-induced luminescent quenching is dominated by the d-d interaction. In view of the spectral overlap between the Bi 3+ emissions and the Eu 3+ excitation spectra , the energy transfer from Bi 3+ to Eu 3+ of the Ba 9 La 2 Si 6 O 24 :Eu 3+ ,Bi 3+ is studied, and it is dominated by a dipole-quadrupole ( d - q ) interaction. Moreover, upon excitation at 365 nm, the emissions broadly tuning from blue, white and to red are achieved by varying the Eu 3+ content. For the white Ba 9 La 2 Si 6 O 24 :Eu 3+ ,Bi 3+ sample, high temperature PL results show that it does not have severe degradation of emission intensity after increasing the temperature from 25 to 300 °C, exhibiting a good thermal stability . To show the potential application in the lighting fields, we fabricate a white light LEDs device by depositing this white phosphor on a 365 nm UV LED chip. As a result, the values, i.e. , a color rendering index (CRI) of 95, luminous efficiency of 80 lm/W, and color temperature (CT) of ~4215 K at chromaticity (0.382, 0.398), are achieved.
研究领域:
材料科学
·
发光材料
·
固态照明
·
无机化学
·
光电子学
✓ 已验证
DOI
高影响因子
MOLECULES
·
2018
·Vol. 24
·期 1
·128
·
IF 3.098
Mingliang Gao,Beihua Bao,Yudan Cao,Mingqiu Shan,Fangfang Cheng,Miao Jiang,Peidong Chen,Li Zhang
Carbonized pollen grains of Typha (CPT) were widely used in clinical for antithrombosis, wound and bleeding in China. In order to ensure the role of drugs, it is very important to control the quality of drugs. However, there is a lack of monitoring methods in the process of charcoal preparation. To characterize the process of CPT, we used thermal analysis, scanning electron microscope (SEM), color measurement, Fourier transform infrared spectrometry (FTIR) and HPLC. In this study, 7 min was the optimal processing time and the heating process condition should be controlled under 272.35 ± 7.23 °C. This comprehensive strategy to depict the whole carbonizing process would provide new ideas for researches on quality control of Traditional Chinese Medicine (TCM) and processing theory of charcoal medicine.Keywords:pollen grains of Typha;thermal analysis;carbonizing process;Fourier transform infrared spectrometry (FTIR)
研究领域:
药学
·
热分析
·
中医
·
光谱学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS RESEARCH
·
2012
·Vol. 27
·期 7
·1006-1013
·
IF 1.434
Guoxin Zhang,Fengxiang Qie,Jianxuan Hou,Shizhong Luo,Liang Luo,Xiaoming Sun,Tianwei Tan
Surface-functionalized magnetic nanoparticles were prepared by a facile one-pot solvothermal method in ethylene glycol solution. Zeta value, size, and magnetic properties could be well tuned by introducing different functional group molecules. Characterizations, including transmission electronic microscopy, scanning electronic microscopy, thermogravimetric analysis, x-ray powder diffraction and vibrating sample magnetometer, and Fourier transform infrared spectrophotometer demonstrated the efficiency of this simple and general synthesis strategy. The hydrophilic magnetic nanoparticles with various surface functional groups and zeta values were evidenced as excellent candidates for bioseparation by extracting DNA molecules from a model mixture of cell fractures.
研究领域:
纳米医学
·
生物材料
·
分子生物学
·
生物分离技术
·
纳米生物技术
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2019
·
IF 4.175
Yabin Zhang,Chan Xu,Fangcheng Wan,Di Zhou,Liu Yang,Haoshuang Gu,Juan Xiong
Flower-like Bi 2 Sn 2 O 7 /Bi 2 WO 6 hierarchical composites with Bi 2 Sn 2 O 7 nanoparticles on Bi 2 WO 6 nanosheet by different Bi 2 Sn 2 O 7 contents were synthesized via a facile two-step hydrothermal method . The composite of Bi 2 Sn 2 O 7 /Bi 2 WO 6 exhibits higher photocatalytic activity toward Rhodamine B (RhB) under visible light than pristine Bi 2 WO 6 and Bi 2 Sn 2 O 7 . Comparatively, 7% Bi 2 Sn 2 O 7 /Bi 2 WO 6 showed the highest photocatalytic activity owing to the best separation efficiency of photogenerated charges. The role of the active species in the process of the degradation is evaluated by using different types of active species scavengers which revealed that the holes ( h + ) and hydroxyl radicals ( OH) were the main active species responsible for the photodegradation of RhB. The photocatalytic mechanism is further proposed based on impedance spectroscopy (EIS) and the calculated energy bands by Mott-Schottky plot, which unfolds the charge transfer and the active species formed in the photocatalytic process. Furthermore, the as-obtained photocatalysts showed good photocatalytic activity after three recycles.
研究领域:
材料化学
·
光催化
·
纳米材料
·
环境功能材料
·
能源与催化
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2018
·
IF 3.779
Mingye Ding,Chunhua Lu,Le Chen,Zhenguo Ji
Traditional FIR (fluorescence intensity ratio)-based optical thermometers, requiring narrow energy gap between two thermally coupled states (TCS) of single rare-earth ion, have inherent drawbacks including low signal discriminability and large measuring error. To overcome the intrinsic limitation, a new thermometry strategy involving the usage of dual-emitting activators with diverse temperature-dependent emission behaviours has been proposed. Impressively, β-NaYF 4 :Ce 3+ /Tb 3+ phosphor exhibits good temperature sensing performance, excellent signal discriminability and superior thermal stability by using the linearly temperature-dependent FIR between Ce 3+ and Tb 3+ as detecting parameter. Hopefully, the developed dual-emitting sample could have a promising application in self-calibrated luminescent thermometry and this strategy provides a reference for developing high-performance optical thermometers.
研究领域:
材料科学
·
光学工程
·
无机化学
·
生物医学工程
·
纳米技术
·
传感器
✓ 已验证
DOI
高影响因子
NEW CARBON MATERIALS
·
2021
·
IF 1.905
Xiang-bao Lin,Chen Hui,Jing Wu,Zhi-gang Wu,Run Li,Hong-bo Liu
Multi-wall carbon nanotubes (CNTs) were modified by nano-TiC using a pressureless spark plasma sintering technology. The TiC-modified CNTs (T-CNTs) were added to mesocarbon microbeads (MCMBs) to prepare high performance isostatically pressed graphite materials. The structures of the T-CNTs and the prepared isotropic graphite materials were characterized by XRD, SEM and TEM. The mechanical and thermal properties of isotropic graphite reinforced by T-CNTs were measured by a micro-controlled electronic universal testing machine, laser thermal conductivity meter and thermal expansion coefficient meter. Results showed that the nano-TiC was successfully grown on the surface of CNTs. Compared with the isotropic graphite prepared from MCMBs without T-CNTs, the isotropic graphite with T-CNTs has a significant improvement in physical properties (density, open porosity and volume shrinkage). Its flexural strength and degree of graphitization increased by 70% and 10%, respectively, and the thermal properties were also improved to some degree.
研究领域:
材料科学
·
碳材料
·
复合材料
·
粉末冶金
·
热学性能
·
机械性能
✓ 已验证
DOI
高影响因子
International Journal of Applied Ceramic Technology
·
2022
·Vol. 20
·期 2
·1194-1204
·
IF 2.328
Song Qi,Fang Guan,Dan Peng,Xuyi Zhang,Wuping Liao
A simple and effective method for preparing ThO 2 ceramics with high density has been proposed. It mainly includes a positive precipitation approach and a conventional sintering process. The SEM images and laser particle size analysis show that the prepared powder exhibits a round-plated shape with a uniform and narrow particle size distribution, which is the key to the densification sintering of ThO 2 ceramics. The XRD analyses confirm that the ThO 2 ceramics sintered at 1590°C were composed of cubic fluorite phase. The effect of sintering temperature on the density of ThO 2 ceramics was also investigated, and a relative density higher than 95% were achieved after sintering at 1590°C for 6 h in an air atmosphere. Moreover, the Vickers hardness was up to 8.49 GPa, the average linear expansion coefficient within 40–800°C was low to 10.97 × 10 −6 /K, and the thermal conductivity and the thermal diffusivity were both higher than most of traditional ceramic materials (16.94–5.86 W/m K and 7.28–1.28 mm 2 /s, respectively, within the temperature range of 25–800°C). The previous great performances are closely related to its high density, which enables it to be a great candidate for nuclear fuels and other potential application fields.
研究领域:
材料科学
·
核材料
·
陶瓷学
·
无机非金属材料
·
固态化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2016
·
IF 5.31
Jian Jiao,Jing Cao,Yu Xia,Lizhen Zhao
Amine functionalized mesoporous silica MSU-J with 3-D connective channel is employed as an effective absorbent for CO 2 . CO 2 adsorption measurements were conducted by gravimetry to investigate the effects of (i) framework structure, (ii) mesoporous structure, (iii) the type of organic amine, (iV) hydrolyzation treatment, (V) cycle performance. Comparing with tetraethylenepentamine (TEPA) functionalized SBA-15, TEPA functionalized MSU-J has lower gas diffusion resistance. The CO 2 uptake of 25MSU-J is 139.6 mg·g −1 , which is almost 2.5 times than that of SBA-15 of 58 mg·g −1 at 20 wt% TEPA loading. The different textured MSU-J is synthesized at 25 °C, 45 °C, 65 °C and impregnated with TEPA. 65MSU-J synthesized at 65 °C exhibits the larger pore size (16.2 nm) and CO 2 adsorption capacity due to pore size instead of larger specific surface area is more feasible for CO 2 diffusion. The MSU-J is impregnated with tetraethylenepentamine (TEPA), diethylenetriamine (DETA), triethylenetetramine (TETA). TEPA impregnated MSU-J possesses higher thermostability (200 °C) and CO 2 capture (164 mg·g −1 ) than counterparts, due to higher N content and the stronger combination between support and amine. The regeneration of Si OH from Si O Si effectively improves the CO 2 adsorption capacity. Both MSU-J and hydrolyzing MSU-J exhibit good cycle performance of CO 2 capture after 6 times cycle.
研究领域:
材料科学
·
环境化学
·
吸附技术
·
能源工程
·
纳米材料
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 1
·49612
·
IF 2.52
Jianbing Cui,Bo Mu,Baoping Yang,Jinfeng Cui,Junhong Guo,Li Tian,Xia Wang
Self-lubricating composite with stimuli-responsive properties attracts great interest in recent years. Herein, mesoporous silica (MS) as oil-laden containers is explored to achieve self-lubricating feature. The as-prepared MS possesses a high Brunauer-Emmett-Teller (BET) surface area (1,542.35 m 2 /g), which satisfies the criterion for construction of ideal repository for storing enough liquid lubricants. In addition, the thermal stimuli-responsiveness behavior of the oil-laden mesoporous silica (OMS) for lubrication has been investigated by thermogravimetric analyzer tester. As expected, an excellent tribological performance (friction coefficient and wear rate decreased by 63.29 and 82.63%) is obtained by adding 10 wt% OMS into the polyurathene matrix, showing great promise for self-lubricating application.
研究领域:
材料科学
·
高分子材料
·
摩擦学
·
功能材料
·
智能响应材料
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2017
·
IF 2.986
Zhangyi Huang,Jianqi Qi,Mao Zhou,Yichao Gong,Qiwu Shi,Mao Yang,Wei Han,Zhangkai Cao,Shuting Peng,Tiecheng Lu
A facile solvothermal method has been developed to synthesize Gd 2 Zr 2 O 7 nanopowders with well-controlled particle size and dispersion. The nanopowders were consolidated into dense ceramic pellets by pressureless sintering, and effects of the solvothermal method in microstructure control are demonstrated by comparison with conventional precipitation approach. X-ray diffraction, electron microscopy , gas adsorption, and a standard operating procedure (SOP) in Malvern Instruments were employed to investigate crystallite/grain sizes and structural morphology evolutions of nanopowders and ceramics. Well-crystallized Gd 2 Zr 2 O 7 nanopowders with little agglomeration and narrow size distribution synthesized by this method have an average crystallite size of 3.5 nm and high surface area of 162 m 2 /g. This method also allows the formation of homogeneous and dense Gd 2 Zr 2 O 7 ceramic with bulk density over 94% of the theoretical value achieved after sintering at 1500 °C for 6 h.
研究领域:
材料科学
·
无机非金属材料
·
纳米材料化学
·
陶瓷学
·
固态化学
✓ 已验证
DOI
高影响因子
Device
·
2024
·
IF 0
Fangfang Deng,Primož Poredoš,Jiaqi Yu,Zhihui Chen,Chengjie Xiang,Xinge Yang,Ruzhu Wang
Sorption-based atmospheric water harvesting (SAWH) is promising for addressing water scarcity due to its wide global applicability. However, given their weak heat and mass transfer properties, most existing SAWH systems remain uncompetitive in fresh water production in most practical scenarios. Here, we present a modular water harvester (MWH) with a serial modular design to achieve advanced heat and mass management. The device can perform sorption kinetics without any power equipment, reduce heat radiation to semi-decouple the desorption and condensation process, and induce thermal buoyancy to enhance water vapor transport via the chimney effect. The MWH reports 3.78 kg m −2 day −1 and 1.66 kg kg −1 sorbent day −1 of water productivity outdoors, which is the highest yield among reported passive SAWH devices.
研究领域:
环境科学
·
能源工程
·
材料科学
·
可持续技术
·
热力学
✓ 已验证
DOI
危险品化学品经营许可证（带存储）