Materials Chemistry Frontiers
·
2019
·Vol. 3
·期 10
·2120-2127
·
IF 0
Qiang Zhang,Xicheng Wang,Zuobin Tang,Yuhua Wang
A novel blue-emitting phosphor, Na3ScSi2O7:Ce3+ (NSSO:Ce3+), was synthesized with a solid-state method at low temperature successfully. Its crystal structure, band structure, and photoluminescence and cathodoluminescence properties were researched in detail. The phase formation and the crystal structure were confirmed by powder X-ray diffraction analysis and the Rietveld refinement method, respectively. Under the excitation of n-UV light, the optimal NSSO:0.02Ce3+ phosphor can yield blue emission centered at 452 nm with a high quantum efficiency of 50.9%. The PL intensity of the NSSO:0.02Ce3+ phosphor remains at 71.46% of the initial value when the temperature is increased from room temperature to 150 °C, indicating good thermal stability. A WLED lamp was obtained by combining a 360 nm n-UV chip with Sr2SiO4:Eu2+, (Ca, Sr)AlSiN3:Eu2+ and NSSO:0.02Ce3+ phosphors, in which the color coordinates, CCT and CRI are (0.360, 0.348), 4409 K and 90.9, respectively. Moreover, under low voltage electron bombardment, the phosphor can emit blue emission with high luminescence intensity, current saturation and resistance. All the results indicate that the NSSO:Ce3+ phosphor shows much potential for the application of both WLEDs and field emission displays (FEDs). Our research has also offered a new insight and perspective that using Sc-based sorosilicates as host can be an appropriate strategy for developing excellent inorganic luminescence materials.
研究领域:
材料科学
·
光学工程
·
无机化学
·
固态照明
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显示技术
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DOI
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
·
2017
·Vol. 315
·期 2
·243-250
·
IF 1.282
Deng Xiangyi,Feng Yali,Li Haoran,Yuan Fei,Teng Qing,Wang Hongjun
The Pseudomonas monteilii . YL-1 was cultured from deep sea sediment to remove uranium from aqueous solution. Different influence factors on uranium adsorption efficiency were investigated. The kinetic model of Pseudomonas monteilii could be described by the pseudo-second-order kinetic model, and the Freundlich isotherm model could fit the experiment data well, indicating that the adsorption was multilayer adsorption. The adsorption was spontaneous and endothermic reaction by thermodynamic analysis. The functional groups of Pseudomonas monteilii such as hydroxy, carboxyl, amino and amide may act with UO 2 2+ by chemisorption or strong complexation in the process of uranium adsorption.
研究领域:
微生物学
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环境科学
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生物修复
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重金属污染治理
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海洋微生物资源
✓ 已验证
DOI
高影响因子
CRYSTENGCOMM
·
2023
·Vol. 25
·期 11
·1675-1682
·
IF 3.1
Junai Lv,Qi Li,Xin Guan,Na Lin,Jian Zhang,Zhitai Jia,Xutang Tao
Selenite and tellurite compounds have garnered a lot of attention in both fundamental and applied chemistry. Se4+ and Te4+ cations possess lone pair electrons, which change the coordination environments and performance of these compounds. Here, three new transition metal selenite and tellurite compounds, MSe2O6 (M = Zr, Hf) and HfTe3O8, have been obtained by conventional hydrothermal reactions. The crystallographic structures of the three compounds are discussed in detail; meanwhile, thermal analysis, optical spectra, birefringence and theoretical calculations are also reported. Isostructural ZrSe2O6 and HfSe2O6 exhibit partially distorted octahedral and tetrahedral configurations. Moreover, ZrSe2O6 and HfSe2O6 have birefringence (Δn = 0.1052, 0.096) and short UV cut-off edges (212, 208 nm), and compared with ZrSe2O6, the thermal stability of HfSe2O6 is slightly larger. ZrSe2O6 and HfSe2O6 are adequate candidates as birefringent crystals in the UV region. Remarkably, HfTe3O8 not only has high thermal stability, but also provides a short UV cut-off edge (234 nm). It can meet the multiple requirements of the developing photoelectric system for UV window materials and has broad application prospects. Furthermore, the intrinsic relationship between the physical properties of the three crystals and their unique electronic structures is revealed.
研究领域:
材料科学
·
无机化学
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光学工程
·
晶体学
·
物理化学
✓ 已验证
DOI
高影响因子
CELLULOSE
·
2015
·Vol. 22
·期 4
·2787-2796
·
IF 3.573
Gao Wei-Wei,Zhang Guang-Xian,Zhang Feng-Xiu
In this study, a novel, halogen-free, formaldehyde-free, organic phosphorus-based flame retardant, ammonium salt of hexamethylenediamine- N , N , N ′, N ′-tetra(methylphosphonic acid) (AHDTMPA), was synthesized using urea and hexamethylenediamine- N , N , N ′, N ′-tetra(methylphosphonic acid) (HDTMPA). AHDTMPA reacted with the O-6 hydroxyls of glucose residues in the cellulose of cotton fabric to form P–O–C covalent bonds. This ability was confirmed by Fourier-transform infrared (FTIR) spectroscopy, attenuated total reflection FTIR spectroscopy, and X-ray diffraction. Cotton fabric treated with 70 g/L AHDTMPA had a limiting oxygen index (LOI) value of 36.0 %, which remained relatively stable after 50 laundering cycles with a 28.0 % LOI value. The surface morphology and thermal stability of treated cotton fabrics were investigated using scanning electron microscopy and thermogravimetric analysis (TGA), respectively. TGA showed that AHDTMPA could exhibit flame retardancy at temperatures lower than the pyrolysis temperature of cotton fabrics. Additionally, the cotton fabric was treated with AHDTMPA through a pad-cure process, as its ease of operation, high efficiency, and excellent application made it an attractive treatment.
研究领域:
材料科学
·
纺织工程
·
高分子化学
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阻燃技术
·
表面改性
✓ 已验证
DOI
高影响因子
CRYSTENGCOMM
·
2012
·Vol. 14
·期 23
·7942-7950
·
IF 3.842
Heng Zhang,Yi Lu,Chang-Dong Gu,Xiu-Li Wang,Jiang-Ping Tu
A new strategy for synthesizing Ni–P alloy nanoparticles with a core-shell structure is proposed, which involves a facile ionothermal process in a deep eutectic solvent (DES). The architecture of the core-shell structured Ni–P alloys is featured as amorphous spherical cores homogeneously wrapped by self-generated crystalline Ni3P shells of different thickness, which rely on the molar ratio of Ni2+/H2PO2− in the choline chloride (ChCl)/ethylene glycol (EG) based eutectic mixture. As an anode for lithium ion batteries, cyclic voltammetry curves, electrochemical impedance spectra, and cyclability of the novel structured Ni–P nanoparticles were evaluated. It was found that the sample with a thicker crystalline shell exhibited improved capability and reversibility over the sample with a thinner one, especially at a higher discharge–charge current density. It was suggested that the crystalline shell can enhance the conductivity of the amorphous cores, suppress the aggregation of active particles and increase the structural stability during cycling.
研究领域:
材料科学
·
电化学
·
能源存储
·
纳米技术
·
合金设计
✓ 已验证
DOI
高影响因子
ACS Applied Optical Materials
·
2024
·
IF 0
Xunsheng Zhou,Binqing Zhao,Lu Yao,Wanting Gui,Longfei Chen,Chao Li,Shi Zhang,Cai Lin Wang
Eutectic scintillators with 6Li-containing thermal neutron absorbers are capable of efficient thermal neutron detection due to lamellar or rod-like optical waveguide structures formed by directional solidification. However, developing stable and bright eutectic scintillators with excellent neutron imaging capability remains a challenge. Here, the performance parameters for the scintillator have been substantially improved by the Al3+ codoping strategy in the LiF-CaF2:Eu2+ system. Due to the Al3+ codoping, the photoluminescence quantum yield (PLQY) is enhanced from 55% to 80%, the light yield is increased from 11,000 to 16,000 photons/thermal neutron, and the scintillation decay time is shortened by about 30 ns. It was shown that Al3+ codoping can effectively reduce the low-frequency shallow-energy level traps. Furthermore, large-sized (50 × 50 × 1.5 mm) translucent LiF-CaF2:Eu2+, Al3+ eutectic ceramics have been fabricated for an Anger-logic position-sensitive detector to realize two-dimensional (2D) thermal neutron detection. A codoped LiF-CaF2 eutectic scintillator provides a ∼1 mm spatial resolution and thermal neutron detection efficiency 16% higher than that of a commercial GS20 scintillator. This research paves the way for the application of large-area eutectic scintillators for efficient thermal neutron detection.
研究领域:
材料科学
·
核物理
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光学
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DOI
Nano Select
·
2021
·Vol. 2
·期 7
·1403-1416
·
IF 0
Bin Yang,Yang-nan Yu,Yang Pan,Shu-qing Wang,Xiang Xu,Ying-ying Wang,Jia-sheng Qian,Ru Xia,Peng Zhang,You Shi,You-lei Tu
In this research, series of PVDF microporous films with various polymer concentrations and thickness were prepared through thermally-induced phase separation in air condition with diphenyl carbonate as the diluent. Effects of polymer concentration and film thickness on the formation kinetics of microporous structure of PVDF thin films were in situ investigated via TII technique. The instantaneous heat conduction inside the films during film formation was also evaluated. Two types of parameter models were adopted in order to disclose the time and location dependence of TIPS film solidification kinetics, respectively. Hierarchical microstructures, crystallization behavior and thermal properties of the TIPS films were also characterized by SEM, DSC, and TGA, respectively. The current study could supply an insight into the fabrication of PVDF microporous films with target microstructure and desirable performance.
研究领域:
材料科学
·
高分子化学
·
膜科学技术
✓ 已验证
DOI
CELLULOSE
·
2019
·Vol. 26
·期 3
·1577-1593
·
IF 3.917
Jiang Yan,Liu Xiuyu,Yang Qiang,Song Xueping,Qin Chengrong,Wang Shuangfei,Li Kecheng
Abstract This study investigated effects of residual lignin on composition, structure and properties of cellulose fibrils and cellulose fibril-based films by comparing two groups of cellulose fibrils which contained different amounts of lignin (15% and 2%, respectively) but were similar in cellulose to hemicellulose ratio. The results showed that lignin affected the size and content of nanofibril in cellulose fibrils through initially delaying but ultimately facilitating the mechanical defibrillation. Due to higher thermal stability and strong UV absorption capability, lignin enhanced the thermal stability and UV blocking properties of cellulose fibril-based film. Hydrophobic lignin also improved the dewatering of cellulose fibrils and the hydrophobicity of cellulose fibril-based film. Lignin interfered with the interfibrillar hydrogen bonding and therefore increased the mesopore diameter of cellulose fibril network. Lignin acting as a cement in cellulose fibril-based film made the film with a more densely packed structure, a higher density and a smoother surface. However, lignin decreased the transparency of cellulose fibril-based film due to its chromophore groups and impaired the mechanical strength of cellulose fibril-based film through interfering with the interfibrillar hydrogen bonding. Graphical abstract
研究领域:
材料科学
·
植物学
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY
·
2024
·
IF 4.3
Jin Yang,Jianhao Zha,Qinan Mao,Heyi Yang,Lang Pei,Jiasong Zhong
Indoor plant cultivation has been receiving increased attention due to concerns about sustainable agricultural production. Phosphor-converted light-emitting diodes (pc-LEDs) offer substantial promise as lighting solutions for regulating plant growth. However, the quest for high-performance phosphors with precise responsiveness to far-red phytochromes poses a challenge. Our study proposes a chemical substitution strategy to develop near-infrared (NIR) phosphors, YAl3–xGax(BO3)4:Cr3+. Benefiting from Ga3+ replacement of Al3+, a red shift in the NIR emission of YAl3–xGax(BO3)4:Cr3+ is realized to attain a good alignment with far-red phytochrome absorption centering at 730 nm. The optimized YAl2.5Ga0.5(BO3)4:Cr3+ exhibits a favorable quantum yield of 71.8% and robust thermal stability of 101.0%@423 K, owing to local structural distortion and thermal repopulation caused by Ga3+ incorporation. The fabricated pc-LED combined with the phosphor yields an NIR output power of 40.9 mW and a photoelectric conversion efficiency of 15.4% at 100 mA. Plant growth experiments demonstrate that under NIR illumination from the devices, the average lengths of pea roots and stems gain 127 and 225% promotion, respectively, further highlighting the potential of YAl2.5Ga0.5(BO3)4:Cr3+ phosphors for applications in plant cultivation.
研究领域:
材料科学
·
光电子学
·
园艺照明
·
固态照明
·
光生物学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2018
·
IF 3.057
Chao Peng,Ping Wei,Xin Chen,Yongli Zhang,Feng Zhu,Yonghai Cao,Hongjuan Wang,Hao Yu,Feng Peng
2D MXenes have attracted extensive attentions owing to their anisotropy, high conductivity and other extraordinary properties. The popular preparation method of MXenes usually involves HF in high concentrations, which has seriously restricted their pervasive applications. In this work, a new hydrothermal route with low-toxicity etching agents (NaBF 4 , HCl) was used to synthesize Ti 3 C 2 MXene ( h- Ti 3 C 2 ). Compared with the Ti 3 C 2 prepared by the traditional HF etching method ( t- Ti 3 C 2 ), the h- Ti 3 C 2 has the higher c lattice parameter , larger interlayer distance and larger BET specific surface area, because of the slow release mechanism during the hydrothermal process. The hydrothermal etching method not only avoided the use of high-concentration HF, but also was more efficient to prepare Ti 3 C 2 flakes. Moreover, the hydrothermal etching route can be extended to other MXene materials, e.g. Nb 2 C. We demonstrated that the h -MXenes have better adsorption performance of methylene blue and methyl orange dyes. The hydrothermal etching route proposed in this study enabled the environmental benign and high efficiency exfoliation of MXenes, displaying the promise to facilely prepare 2D MXenes and paving a way to their widespread applications.
研究领域:
材料科学
·
纳米材料
·
环境功能材料
·
表面化学
·
胶体与界面科学
✓ 已验证
DOI
高影响因子
IONICS
·
2016
·Vol. 23
·期 4
·985-996
·
IF 2.119
Sun Kanjun,Li Jindan,Peng Hui,Feng Enke,Ma Guofu,Lei Ziqiang
Nitrogen-doped porous activated carbons (N-PHACs) have been successfully synthesized using pomegranate husk as carbon precursor via ZnCl 2 -activation carbonization and subsequent urea-assisted hydrothermal nitrogen-doping method. The obtained N-PHACs possesses abundant mesoporous structure, high specific surface area (up to 1754.8 m 2 g −1 ), pore volume (1.05 cm 3 g −1 ), and nitrogen-doping content (4.51 wt%). Besides, the N-PHACs-based material showed a high specific capacitance of 254 F g −1 at a current density of 0.5 A g −1 and excellent rate performance (73% capacitance retention ratio even at 20 A g −1 ) in 2 M KOH aqueous electrolyte, which is attributed to the contribution of double-layer capacitance and pseudocapacitance. The assembled N-PHACs-based symmetric capacitor with a wide operating voltage range of 0–1.8 V exhibits a maximum energy density of 15.3 Wh kg −1 at a power density of 225 W kg −1 and superior cycle stability (only 6% loss after 5000 cycles) in 0.5 M Na 2 SO 4 aqueous electrolyte. These exciting results suggest that the novel N-doping porous carbon material prepared by a green and low-cost design strategy has a potential application as high-performance electrode materials for supercapacitors.
研究领域:
材料科学
·
电化学
·
纳米能源
·
储能材料
·
碳材料
✓ 已验证
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2020
·
IF 3.807
Yiping Sun,Houcai Dong,Kuan Wu,Xi Chen,Shaofei Wang,Wei Gu,Ziwei Hong,Min Liu,Yanbin Shen,Wei Lu
Surface coating is an efficient strategy to enhance the interfacial stability of the electrode. Graphene quantum dots (GQDs) have advantages of excellent dispersion in water, outstanding electron and ion conductivities and high specific surface area. In this work, GQDs were coated directly on the surface of LiCoO 2 particles (GQDs-LiCoO 2 ) through liquid phase method. Compared to bare LiCoO 2 , the cycling performance, rate capacity and thermo-stability of the GQDs-LiCoO 2 have been significantly improved in the voltage range of 3.04.5 V. GQDs-LiCoO 2 showed a much higher capacity retention than that of bare LiCoO 2 (82.8 % vs 46.1 %) after 100 cycles at 0.5 C. The excellent improvement of the GQDs-LiCoO 2 was mainly attributed to the formation of a uniform, stable, dense and well-conductive protective layer on the surface of LiCoO 2 particles by the surface coating of GQDs. The detailed analysis of the cycled electrodes reveals that the GQDs coating stabilizes the crystal structure of LiCoO 2 and suppresses undesirable interfacial side reactions between the cathode and electrolyte, leading to the improvement of battery performance.
研究领域:
材料科学
·
电化学
·
能源存储
·
锂离子电池
·
界面工程
✓ 已验证
DOI
高影响因子