APPLIED SURFACE SCIENCE
·
2015
·
IF 2.711
Xiaohang Zeng,Yanqiong Ma,Yuechuan Wang
Stabilizing long-term, low energy surface properties is a key issue in designing fluorinated polymer network, because the fluorinated surface could reorganize or hydrolyze upon contact with water. Here we report an exploring to enhance the low energy surface performance by bonding a dangling shell of fluorinated block copolymer, poly((1H,1H,2H,2H-perfluorodecyl acrylate)-b-poly(caprolactone) (PFDA-b-PCL)), to the polyurethane network. The PFDA and PCL block are the fluorinated shell and the dangling chain, respectively. The fluorinated shell protects the surface from rearrangements and hydrolysis when in contact with water, while the soft polyester block provides the required flexibility for fluorinated components to segregate to the surface. Surfaces with water contact angle up to 120° and surface energy down to 18 mN/m were obtained. We then evaluated the effects of fluorinated species on the surface properties of the polyurethane network both with and without the fluorinated shell or polyester spacer. The surfaces functionalized with the fluorinated dangling shell are highly hydrophobic and exhibited better hydrophobic stability. The oligoester spacer connecting the fluorinated shell to the polymer network is critical for the segregation and rebuilding of low energy surfaces.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
COMBUSTION SCIENCE AND TECHNOLOGY
·
2023
·
IF 1.9
Hao Shi,Chunlong Jiang,Haobo Bi,Zhanshi Ni,Hao Sun,Yurou Yao,Qizhao Lin
This study investigates the effect of potassium fluosilicate (K2SiF6) on the ignition and heat release characteristics of n-Al50, n-Al100, and n-Al800. It is found that K2SiF6 can effectively improve the ignition and heat release characteristics of nano-aluminum powder (n-Al). This is because K2SiF6 effectively increases the reaction rate. The heat release characteristics of the n-Al/K2SiF6 mixture are improved as the particle size of aluminum powder decreases and the heating rate increases. However, when the particle size reaches a certain level, the enhancement effect will become smaller and smaller. The study revealed that the addition of K2SiF6 influences the ignition delay time, reaction, and combustion products of the n-Al/K2SiF6 mixture. A small amount of K2SiF6 can greatly reduce the ignition delay time of nano-aluminum powder. With the increase of K2SiF6 content, the ignition delay time of n-Al50 decreases first and then increases, while the ignition delay time of n-Al100 and n-Al800 decreases continuously but the extent of this reduction progressively diminishes. The morphology and composition of the combustion products were analyzed. This paper found that K2SiF6 fluorinates the oxidized shell of aluminum, thereby promoting its ignition and combustion. The influence mechanism of K2SiF6 on n-Al ignition in air is discussed.
研究领域:
材料科学
·
燃烧学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Energy Technology
·
2022
·Vol. 10
·期 6
·2200155
·
IF 4.149
Delun Zhu,Jingchao Yuan,Yang Dai,Yuqing Peng,Wenrong Li,Fangzhou Zhang,Aijun Li,Jiujun Zhang
The lithium–fluorinated carbon (Li/CF x ) battery possesses the highest energy density (2180 Wh kg −1 ) among all the primary lithium batteries. However, the poor electronic conductivity of the fluorinated carbon (CF x ) material sets a limit on its rate discharge capability, confining its practical application. In this article, a doping strategy at a mild anneal condition is developed to synthesize the phosphorus species-doped CF x materials (P-CF x ) for Li/CF x batteries. Compared to the commonly used methods, this eco-friendly, and simple doping method does not involve washing, centrifugation, and filtration processes. Characterization using X-Ray diffraction, high-resolution transmission electron microscope, and X-Ray photoelectron spectroscopy confirms the successful doping and the structure of the P-CF x . Density functional theory calculations and characterization results demonstrate that phosphorus species doping can alter microstructure and induce charge redistribution to improve electronic and ionic conductivity. Therefore, the Li/P-CF x battery possesses a high specific capacity and an excellent rate capability, shown by a high discharge capacity of 810 mAh g −1 with a voltage plateau of 2.53 V at 0.1 C. Extraordinarily, a discharge capacity of 597 mAh g −1 with a voltage plateau of 1.90 V at 20 C has been achieved as well as a high power density of 34 048 W kg −1 .
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Sciences
·
2023
·
IF 6.9
Xi Tan,Yan Shi,Chun-Feng Ma,Quan Chi,Yu-Hang Yang,Wen-Xiang Zhang,Hua-Ming Xiao,Xian Wang
Perfluorinated compounds (PFCs) are toxic and widely present in the environment, and therefore effective adsorbents are required to remove PFCs from environmental water. In the present study, a new type of fluorinated biomass materials was synthesized via an ingenious fluorosilanization reaction. These adsorbents were applied for the adsorption of 13 typical PFCs, including perfluorocarboxylic acids (PFCAs) and perfluorosulfonic acids (PFSAs). By comparing their adsorption performance, Fluorinated cedar slag (FCS) was discovered to have the best absorption efficiency and enabled highly efficient enrichment of PFCs. The adsorption recovery of FCS with the investigated PFCs is greater than 90% under the optimal adsorption condition. Ascribed to the high affinity of F-F sorbent-sorbate interaction, FCS had good adsorption capacities of PFCs from aqueous solution, with the maximum adsorption capacity of 15.80 mg/g for PFOS and 10.71 mg/g for PFOA, respectively. Moreover, the adsorption time could be achieved in a short time (8 min). Using the FCS absorbent, an innovative FCS-solid phase extraction assisted with high performance liquid chromatography-electrospray-tandem mass spectrometry (FCS-SPE-HPLC-ESI-MS/MS) method was first developed to sensitively detect PFCs in the environmental water samples. The intra-day and inter-day recovery rates of the 13 compounds ranged from 90.7%-104.3%, with the RSD of 2.1%-4.7% (intra-day) and 2.5%-8.5% (inter-day), respectively. This research demonstrates the potential of the newly fluoro-functionalized plant biomass to adsorb PFCs from environmental water, with the advantages of high adsorption efficiencies, high anti-interference, easy operation and low economic cost.
研究领域:
环境科学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2023
·
IF 6.6
Xinlei Wu,Jia Cao,Sijia Zheng,Zhihai Cao
Low surface energy and low surface reconfiguration are two key properties being sought for fluorinated polymer films with short perfluoroalkyl groups, which are mainly determined by the molecular structure of fluorinated monomers . In this work, six typical C6 fluorinated monomers were selected to synthesize fluorinated polymer nanoparticles (f-PNPs) through miniemulsion polymerization. Fluorinated polymer films were further fabricated through spin-coating by using f-PNPs as the building blocks. Influences of the molecular structure of fluorinated monomers and heat treatment conditions on the surface element composition, arrangement of fluorinated side chains, surface morphology , surface performance, and underwater surface configuration of fluorinated polymer films were systematically investigated. The results showed both the fluorinated side chain structure and α-position substitution of fluorinated monomeric units played a significant role in the surface F enrichment extent, organized arrangement of fluorinated side chains at the surface, surface morphology, and finally the surface free energy . Generally, fluorinated polymer films with linear fluorinated side chains ended with –CF 3 displayed stable low surface energy and low surface reorganization attributed to forming relatively organized packing structures of fluorinated side chains. This study contributes to providing a guide to design and fabricating low surface free energy nanomaterials or films with perfluoroalkyl (meth)acrylate copolymers bearing short perfluoroalkyl groups.
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
POWDER TECHNOLOGY
·
2025
·
IF 4.6
Xueqin Liao,Jianzhong Liu,Mengxia Sun,Xiaohui Xue
Fluoride has shown great potential for improving the burning rate and combustion efficiency of aluminum (Al) particles. Herein, the effects of metal fluoride (ferric fluoride, FeF 3 ) and organic fluoride (polytetrafluoroethylene, PTFE) on the combustion of Al particles were comparatively investigated using various characterization methods. The results showed that both FeF 3 and PTFE could improve the thermal reaction properties of Al particles, including thermal oxidation rate, heat release, mass gain, and thermal oxidation efficiency, and the improvement of FeF 3 was better. Thermal reaction curves and tube furnace tests together demonstrated that fluoride and Al particles undergo pre-ignition reaction at low heating rates. Combustion diagnostic results and condensed combustion products (CCPs) analysis of the samples revealed that both fluorides reduced the ignition delay time and increased the combustion intensity, burning rate, combustion efficiency and maximum combustion temperature. When ammonium perchlorate (AP) was not added, PTFE improved the combustion performance of Al particles better due to its high gas production characteristics. PTFE is not as good as FeF 3 after adding AP. Furthermore, varying the FeF 3 content in the binary mixture (Al/FeF 3 ) between 5 % and 20 % did not significantly affect the combustion characteristics of the samples. Interestingly, the high-speed camera captured the jetting phenomenon of Al droplets during combustion, which is attributed to the erosive effect of F on the alumina cap. The jet phenomenon is the direct evidence of the reaction between Al particles and F during combustion, which provides new insights into the complex reaction mechanism between the two. Statistics on a large number of particles indicated that FeF 3 can increase the frequency of the particle jet phenomenon. Finally, the phenomenological mechanism of fluoride promoting Al particle combustion is proposed. Considering the catalytic effect of metals and their corresponding oxides on AP, the addition of metal fluorides to AP-based energetic materials may be a more preferable option.
研究领域:
材料科学
·
燃烧学
✓ 已验证
产品关联
DOI
高影响因子
SYNTHESIS-STUTTGART
·
2024
·
IF 2.2
Taijie Guo,Wei Wang,Long Xu,Jiajia Dong
Here we report the utilization of NH-sulfamoyl fluorides (RNHSO2F) as reliable SuFEx synthons for the construction of various sulfamate esters. By using potassium fluoride as base, we are able to convert RNHSO2F to azasulfene intermediates under mild conditions and guarantee their further efficent ligation with phenols and alcohols.
研究领域:
有机化学
·
合成化学
✓ 已验证
DOI
高影响因子
CHEMISTRY OF MATERIALS
·
2020
·
IF 9.567
Minqiang Gai,Tinghao Tong,Ying Wang,Zhihua Yang,Shilie Pan
By the selective fluorination of IO4 in iodates, SrI2O5F2 (SIOF) and Ba(IO2F2)2 (BIOF) were synthesized successfully. They are the first reported cases of alkaline-earth metal fluoroiodates, and the (IO3F)2– units in SIOF were discovered for the first time to the best of our knowledge. BIOF possesses the shortest UV cutoff edge (230 nm), and SIOF has the largest birefringence (cal. 0.203 at 532 nm) among the reported fluoroiodates. The highly polarizable (IO3F)2–, with high polarizability anisotropy, induces a large birefringence in SIOF by theoretical calculation. This work will contribute to enlarge the structural diversity and provide a good choice for the material design in fluoroiodates.
研究领域:
无机化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2023
·
IF 3.6
Runfa Liu,Yue Pan,Jia Zhang,Xincui Zhuang,Yangbo Wang,Xufeng Zhou,Shanshan Du,Huaiyong Li,Wei Li
Ratiometric luminescence thermometry is awfully applicable for non-contact temperature detection. Lanthanide luminescent materials available for high-performance ratiometric thermometry are still highly desirable until now. Herein, two novel upconversion phosphors, Yb 3+ /Ho 3+ co-doped BiOF and BiF 3 microcrystals , were synthesized and investigated systematically in terms of their crystalline structure, room temperature and temperature-dependent upconversion properties. Under 980 nm laser excitation, both microcrystals bring forth the characteristic emissions of Ho 3+ , with an identical overall luminescent color of green, while the intensity is much higher in BiF 3 :Yb/Ho microcrystals. When increasing temperature, the upconversion intensity at various wavelengths for both microcrystals is reduced, meanwhile fluorescence intensity ratios of both 545/656 nm and 752/656 nm decrease highly regularly, establishing a ratiometric thermometry therefore. BiF 3 :Yb/Ho microcrystals were demonstrated to have significantly superior thermometric performance than BiOF:Yb/Ho, and a high relative sensitivity up to 5.41% K −1 as well as a wide temperature sensing range of 298–673 K were obtained.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2019
·
IF 3.42
Wentao Li,Wenjie Zhao,Lisha Mao,Shengguo Zhou,Chao Liu,Zhiwen Fang,Xiulei Gao
In this work, fluorinated graphene (FG) nanosheets with different F/C fluorination degree were synthesized by a convenient gas phase fluorination method. Ionic liquids was used to modify the FG to improve its dispersion and compatibility in polyimide (PI). The thermal, mechanical and tribological properties of FG/PI composite coatings were investigated systematically. The morphology of FG was observed by Transmission electron microscopy (TEM) and scanning probe microscope (SPM). The physical and chemical properties of the FG were characterized by a large number of measurement methods, such as X-ray powder diffraction (XRD), Raman spectra, X-ray photo-electronic spectroscopy (XPS) and so on. Fourier transformed infrared spectra (FTIR) was used to confirm the successful modification of ILs. And the Chemical composition of the PI coating was investigated by XPS and FTIR measurements. On the basis of the stable dispersion of FG in the PI matrix, compared with pure PI, the composite coating with (reduced graphene oxide) rGO owned slightly improved thermal, mechanical and tribological properties and the composite coating with FG displayed significant improvement, especially when the F-doped degree was the highest.
研究领域:
材料科学
·
表面工程
✓ 已验证
DOI
高影响因子
IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION
·
2025
·
IF 3.1
Kaixuan Sun,Haoxuan Sun,Xianghan Du,Zixuan Zhao,Geng Chen,Fangcheng Lv,Xiang Yu
Poly(m-phenylene isophthalamide) (PMIA) is renowned for its superior insulating and mechanical properties, holding immense promise in ultra-high voltage transmission systems. To further enhance the mechanical robustness of nanofiber-based paper, microfibers have been employed as reinforcement fillers. However, interfacial issues have emerged as a challenge, compromising the insulation properties. In this work, we present the realization of synergistically enhanced breakdown strength and mechanical properties in the PMIA micro-nano composite paper, achieved by interface fluorination treatment. With an optimized fluorination time of 60 s, the composite structure becomes more compact, greatly enhancing its overall integrity. The fluorine-rich interface provides potential electron traps and hydrogen bond sites, which play a crucial role in enhancing both electrical insulation and mechanical properties. The breakdown strength is increased by 19.5%, achieving a high value of 295.6 kV/mm. Concurrently, Young’s modulus and tensile strength are enhanced to 4.04 GPa and 24.38 MPa with increases of 32.9% and 14.8%, respectively. However, it is noteworthy that excessive plasma fluorination can induce surface structural damage to microfibers, impeding the adhesion of nanofibers. It leads to a deterioration in both electrical and mechanical properties. Moreover, the optimized paper shows exceptional flexibility, foldability, and colorability, opening new avenues for their utilization in demanding electrical environments.
研究领域:
材料科学
·
电气工程
✓ 已验证
产品关联
DOI
高影响因子
CORROSION SCIENCE
·
2020
·
IF 6.479
Zhengqing Yang,Wen Sun,Lida Wang,Zhuang Wan,Jing Wang,Suilin Wang,Guichang Liu
Graphene is cathodic to most metals and can cause promoted corrosion to metals. Herein, we demonstrate that tuning oxygen reduction reaction (ORR) activity of graphene through fluorination modification is an effective strategy that can inhibit the corrosion-promotion activity of graphene. It is revealed that the cathodic ORR activity of partially fluorinated graphene (PFG) decreases with the increase of fluorine (F) content, which consequently increases the depolarization resistance of the cathodic ORR during corrosion. Especially, PFG containing 15.2 wt.% F exhibits a completely negligible corrosion-promotion activity. Furthermore, PFG can also improve the barrier property of polyvinyl butyral coating.
研究领域:
材料科学
·
电化学
·
防腐蚀研究
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）