INORGANIC CHEMISTRY
·
2024
·
IF 4.3
Mei Yan,Ru-Ling Tang,Wei Xu,Wenlong Liu,Sheng-Ping Guo
Zirconium/hafnium fluorides have recently been recognized as potential nonlinear optical (NLO) materials with short ultraviolet (UV) cutoff edges, which is significant in laser science and industry. The synthesis of noncentrosymmetric (NCS) materials based on centrosymmetric (CS) compounds by an isovalent cation substitution-oriented design is an emerging strategy in the NLO territory. Here, two isostructural and novel fluorides, CaBaMF8 (M = Zr (1), Hf (2)), have been synthesized through the combination of alkaline earth metals, zirconium/hafnium, and fluorine elements. They feature zero-dimensional and CS structures composed by an isolated MF8 (M = Zr, Hf) dodecahedron and dissociative Ca2+ and Ba2+ cations, and they display short UV cutoff edges (<200 nm) as well. Two three-dimensional fluorides Li2CaMF8 (M = Zr (3), Hf (4)) are obtained by replacing Ba with alkali metal Li atom, which not only represent phase-matchable second-harmonic-generation activities (0.36, 0.30× KH2PO4 (KDP)) at 1064 nm but also maintain short UV cutoff edges with high reflectance. This work has largely enriched the family of NCS zirconium/hafnium fluorides reaching the short UV region.
研究领域:
材料科学
·
无机化学
·
光学材料
·
晶体工程
·
非线性光学
✓ 已验证
DOI
高影响因子
JOURNAL OF NON-CRYSTALLINE SOLIDS
·
2023
·
IF 3.5
Y. Ji,C.Y. Shao,D.D. Chen,W.C. Wang
Laser glass has been widely used in laser ignition devices, fundamental physical research, and material processing. In addition to the exploration of the glass composition, the optimization of preparation conditions is also of crucial importance to the performance of laser glass. Herein, the modification effect of additional fluorine and sulfur agents on Nd 3+ -doped fluoro-sulfo-phosphate glasses (FSP) has been investigated in detail. The contents of F and S were increased by up to 42% and 40% after agent addition. Fluorine and sulfur agents also decrease the non-linear effect and increase the chemical durability of FSP glasses, respectively. Moreover, the local environment around Nd 3+ ions is examined by electron paramagnetic resonance (EPR)., The direct connection between Nd-F and the possible connection between Nd 3+ and [SO 4 ] 2− have been detected with agent addition, which facilitate the promotion of radiation parameters. The emission cross-section and quantum efficiency of FSP glass increase by up to 56% and 54% after agent addition. This study aims to demonstrate the structure and property variations brought by additional agents, providing insight into the optimization of the melting procedure of high-performance FSP laser glasses.
研究领域:
材料科学
·
光学
·
激光物理
·
玻璃科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Shuhui Liang,Huan Guan,Hainan Zhang,Xiangge Han,Jia Gao,Jiupeng Zhao,Shuliang Dou,Yao Li
With the development of modern communication devices, the demand for intelligent electromagnetic wave (EMW) absorbing materials that dynamically respond to environmental changes is ever-growing. However, the design and fabrication of high-performance EMW absorbing materials with adapt features remains challenging. Here, we report a temperature-responsive composite comprising VO 2 nanowires (NWs) and polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-HFP). Benefiting from the phase transition characteristics of VO 2 and the high aspect ratio of NWs, the composite demonstrates two distinct off/on switchable EMW absorbing performances as the temperature increases at low filler loading of VO 2 . The composite with 10 wt% VO 2 NWs transitions from transmission to absorption, showcasing a maximum change in reflection loss (RL) and effective absorption bandwidth (EAB) values of 53.09 dB and 4.85 GHz at the thin thickness of 2.5 mm and 2 mm, respectively. While the composite with 30 wt% VO 2 NWs shows a switch from absorption to reflection with the highest ΔEAB and ΔRL values of 3.59 GHz (1.5 mm) and 44.29 dB (2.5 mm), respectively. Additionally, radar cross-sectional (RCS) simulations verify the intelligent EMW absorbing performance of the composite. The work provides an effective and sustainable approach to harness the potential of VO 2 for developing tunable and high-performance wave-absorbing materials.
研究领域:
材料科学
·
电磁工程
·
纳米技术
✓ 已验证
DOI
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2018
·
IF 2.88
Yan Zhang,Xiaofeng Yang,Guoxin Sun,Hao Zhang,Xiaolei Liu,Fengqiao Zhu,Shuchun Qin,Ziqi Zhao,Yu Cui
A series of colorimetric and reversible receptors for fluoride anions based on diketopyrrolopyrrole (DPP) were designed and synthesized successfully. The position of nitro substituent on the phenylhydrazide affected the alteration of photophysical properties to varying degrees. While the photoluminescence intensity of receptor 1 was weaker than that of receptor 2 and receptor 3 on account of the formation of intramolecular hydrogen bond deriving from oxygen atom of nitro substituent and hydrogen atom of hydrazide . The receptor 2 was a preferable chemosensor for responding fluoride anions. The fluorescence was quenched in the presence of fluoride anion resulted from the photo-induced electron transfer (PET) effect from the amide. The formation of deprotonation species, which produced by hydrazide N H moiety and F − was answerable for the spectral changes. Especially, the spectral and color responses of receptors could be switched back and forth successively by adding F − and HSO 4 − anions in DMSO solution. These receptors could response fluoride anion sensitively, visually and selectively in a manner of reversible with a low determination.
研究领域:
化学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2017
·Vol. 24
·期 11
·10685-10694
·
IF 2.741
Yu Ying,Wang Wei,Shi Jing,Zhu Siyi,Yan Yachen
The presence of antibiotics in the environment has attracted considerable attention due to their toxicity. In this study, agricultural waste corn bracts (CBs) modified by zirconium cations were utilized to remove levofloxacin (LEV) from wastewater. Zr-modified CBs exhibited a strong adsorption capacity (Q max = 73 mg/g), and their desorption rate could reach 89% by simply adjusting the pH to 11. FTIR and XPS analyses indicated that the mechanism of LEV adsorption included the complexation between the ketone/carboxyl groups of LEV and the Zr atoms and the π-π electron-donor-acceptor interaction. Zr-modified CBs are economic, effective and nontoxic adsorbents. This material not only removes antibiotics from wastewater but also enables recycling and reuse of agricultural waste.
研究领域:
环境科学
·
生物化学
✓ 已验证
DOI
PubMed
高影响因子
Desalination and Water Treatment
·
2015
·
IF 1.173
Yumei Zhang,Lan Yang,Dongtian Wang,Tao Zhang
For resource utilization, water treatment residual sludge (WTRS) and its cerium-modified product (Ce-WTRS) were used as adsorbents to remove F− from aqueous solution. The adsorbent materials were characterized by energy dispersive X-ray, scanning electron microscope, X-ray diffraction, Fourier transform infrared, and specific surface area test techniques. Different experimental conditions such as pH, initial F− concentration, contract time, and temperature were investigated. The appropriate adsorption capacity was achieved in the pH range of 3–9. Adsorption kinetics, isotherm, and thermodynamic studies were used to illustrate the nature of F− onto adsorbents materials. Good fitting of pseudo-second-order kinetics model indicated the chemisorption nature. Further analyses of intra-particle diffusion model were carried out to determine the rate controlling step. It was found that the Langmuir and Temkin isotherm models fitted the experimental data better. The maximum adsorption capacity (qm) determined by Langmuir isotherm model was 15.45 mg/g for Ce-WTRS, 22% higher than WTRS. The negative values of ΔGθ indicated the feasibility and spontaneity of material-fluoride interaction. ΔHθ >0 for Ce-WTRS demonstrated the endothermic nature, while ΔHθ <0 for WTRS suggested an exothermic procedure. Ion exchange and complex reaction were identified as the main mechanism of fluoride adsorption.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
Silicon
·
2023
·Vol. 15
·期 13
·5691-5701
·
IF 3.4
Wu Xinglong,Li Xiaolei,Zhong Jiaqi,Xu Xiaoli,Xu Baoyun,Ai Bo
Silicone resin is a coating material with good performance. The improvement of its thermal stability and hydrophobicity has always been the pursuit of researchers. In this paper, a series of novel UV-curable silicone resins containing perfluorocyclobutyl (PFCB) groups were prepared by co-hydrolytic polycondensation. The structures of the resin precursor MDT-SH were characterized by FT-IR and 1 H NMR. The heat resistance of them was studied by TGA and DSC, and results show that the PFCB groups can significantly improve the high temperature resistance of the resins. Contact angle tests showed that hydrophobicity of them was also enhanced by the PFCB groups.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
MOLECULES
·
2022
·Vol. 27
·期 13
·4147
·
IF 4.927
Canxing Zhao,Rui Shi,Shouchun Li,Penghui Li,Xiaoxue Zhang,Guolin Tong
Novel reactive dyes with mono- and bi-acyl fluoride reactive groups have been designed and synthesized, which are obtained by using 2-amino-8-naphthol-6-sulfonic acid or 1-amino-8-naphthol-3,6-disulfonicacid as the coupling component and 4-aminobenzoyl fluoride (PABF) as the diazo component. Their structures have been defined by nuclear magnetic resonance spectroscopy and ultraviolet–visible spectra (UV—Vis). The novel reactive dyes were evaluated on cotton by using the exhaust dyeing method. The properties were examined in detail, and the results showed that the dye concentration of 4% (o.w.f), pH = 9, and salt-free was the most effective condition. The fixation of the novel reactive dyes on cotton was 60.27% and 64.13%, respectively. The micro-fluorine-containing reactive dyes have favorable dyeing properties owing to the covalent bond formed between the reactive group of dyes and the functional group of cotton fibers, which can achieve salt-free dyeing of cotton.Keywords:acyl fluoride;reactive dyes;cotton fabric;low molecular weight;salt-free
研究领域:
化学
·
纺织科学与工程
✓ 已验证
DOI
PubMed
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2018
·Vol. 20
·期 22
·15192-15202
·
IF 3.906
Jinggao Wu,Maowen Xu,Chun Tang,Guannan Li,Hong He,Chang Ming Li
F-Doping effects on polyaniline-derived carbon coated Li3V2(PO4)3 (Li3V2(PO4)3−xFx@C) as a cathode for high performance Li rechargeable batteries are systematically investigated with a combined experimental and DFT theoretical calculation approach. The results clearly indicate that the doping amount has a significant impact on the rate capability and long cycle life. The optimal material (Li3V2(PO4)2.88F0.12@C) delivers 123.16 mA h g−1@2C, which is close to the theoretical value (133 mA h g−1), while showing a greatly improved cycle stability. Rietveld refinements show that the F− doping does not obey Vegard's Law, which may be attributed to the generated lower valence of V ions. AC impedance spectroscopy shows that the F-doping can achieve faster interfacial charge transfer for higher reaction reversibility. DFT calculations confirm that the lower V2+ (t2g↑)3 does exist in Li3V2(PO4)2.88F0.12, and the mean nearest neighbor Li–O bond length also increases for faster electrochemical kinetics, and further reveal that there is a tendency for a transition from the insulator to the n-type semiconductor due to the F dopant. The combined experimental and calculated results suggest that F-doping indeed greatly facilitates the charge transfer rate of the Li+ insertion/de-insertion process for better reversibility and enhances the Li+ diffusion rate to access the reaction sites, thus resulting in high rate capacity and cycling stability. This work not only offers a facile and effective approach to synthesize high performance Li-ion battery material for very promising practical applications, but also discloses scientific insights on element coating and doping to guide the electrode material design for fast electrode kinetics in energy storage devices.
研究领域:
材料科学
·
电化学
·
理论计算
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2019
·
IF 4.175
Yuanjing Wang,Yayun Zhou,Enhai Song
Mn 4+ -activated fluoride red phosphors have a bright prospect for improving the warm white light-emitting diodes (W-LEDs) performances, whereas there remains some challenges in synthesis, such as reducing the consumption of toxic HF and improving Mn 4+ doping efficiency. Herein, a new phosphor (NH 4 ) 2 NaScF 6 :Mn 4+ (NNSFM) was synthesized by an ammonium salt conversion method, which can effectively reduce HF consuming, enhance reaction rate and doping efficiency. The synthesis mechanism, luminescence properties and W-LEDs performances of the as-synthesized NNSFM have been investigated. Moreover, the lattice structure and doping position have been investigated in detail by the density functional calculations (DFT), which show that Mn 4+ could occupy the Sc 3+ crystallographic site in this structure and simultaneously produce a Na vacancy ( V Na ' ) for charge compensation. Using the NNSFM as red-light component, a warm W-LED device with a high color rendering index (CRI, Ra = 80.6) and low correlated color temperature (CCT = 3006 K) has been achieved. This work presents a new Mn 4+ doped fluoride red phosphor and also develops an environmentally friendly strategy for synthesizing Mn 4+ doped fluoride phosphors.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
高影响因子
Journal of Nanoelectronics and Optoelectronics
·
2017
·Vol. 12
·期 10
·1056-1061
·
IF 0.497
Li Shengbin,Hu Bingxu,Zhang Fan
In this paper, we report the fabrication and characterizations of polyvinylidene fluoride (PVDF)/chitosan and PVDF/polymeric methyl methacrylate (PMMA)/titanium oxide (TiO2) materials membranes for waterproofing applications. The detailed results revealed that with the increase
of chitosan proportion, the anti-hydrostatic pressure value of PVDF/chitosan raised first and then declined. When the proportion of PVDF and chitosan reaches 92:8, the anti-hydrostatic pressure value reaches to 5437 Pa, however, when chitosan exceeds the value, its hydrophobicity was reduced.
In addition, the fibrous membrane prepared from PVDF/PMMA/TiO2 was adopted to make a thermal treatment and 6% TiO2 nanoparticles were added to improve the intensity and anti-water pressure of the fibers. The detailed experiments revealed that when the reaction temperature
reach to 50 °C, the anti-hydrostatic pressure of fibrous membrane is far better than fibrous membrane prepared from PVDF/chitosan. Thus, the results confirmed that by adding 6% TiO2 nanoparticles improves the anti-hydrostatic pressure of fibrous membrane. The observed results
shows that chitosan and TiO2 blended with PVDF are promising material for waterproofing applications.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2022
·
IF 7.336
Wenjie Zhao,Weigang Wang,Guorong Hu,Ke Du,Zhongdong Peng,Xudong Zhang,Huan Li,Zijun Fang,Yanbing Cao
Porous Na 3 V 2 (PO 4 ) 2 F 3 (NVPF) with micro-nano structure was prepared by a simple deep-eutectic solvent method with good crystallinity and uniformity. Surface modification was used to produce carbon-coated NVPF (NVPF/C). The unique morphologic architecture and surface modification improve the structural stability and interfacial chemical stability of NVPF, ensuring the excellent rate performance and cycle stability of NVPF/C. At 120 °C, secondary microspheres NVPF composed of nanoparticles are successfully synthesized. By liquid phase reaction in a deep-eutectic solvent X-ray diffraction analysis reveals that these microspheres have good crystallinity . The NVPF/C with an amorphous fluorocarbon coating layer is constructed by pyrolysis of polytetrafluoroethylene (PTFE). The mesoporous structure and the existence of the coating layer are clearly obvious under the high-definition transmission electron microscope. The amorphous fluorocarbon layer enhances the reversibility and transmission ability of Na + , improving the electrochemical kinetics. And the obtained NVPF/C cathode material displays high-rate performance. The as-prepared NVPF/C-F composites with 6 %wt coating of PTFE have a specific capacity of 110.6 mAh g −1 at 10 C, 106.4 mAh g −1 at 20 C and 94.6 mAh g −1 at 50 C. The capacity retention rate is 90.4 % after 700 cycles at 20 C. This research provides a facile and inexpensive approach for getting high-rate performance sodium-ion battery cathode materials.
研究领域:
材料科学
·
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）