NANO LETTERS
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2022
·
IF 12.262
Yangqin Liu,Yilong Jiang,Junhui Sun,Yang Wang,Linmao Qian,Seong H. Kim,Lei Chen
Atomically thin two-dimensional (2D) materials are excellent candidates for utilization as a solid lubricant or additive at all length scales from macro-scale mechanical devices to micro/nano-electromechanical systems (MEMS/NEMS). In such applications, wear resistance of ultrathin 2D materials is critical for sustained lubrication performance. Here, we investigated the wear of fluorinated graphene (FG) nanosheets deposited on silicon surfaces using atomic force microscopy (AFM) and discovered that the wear resistance of FG improves as the FG thickness decreases from 4.2 to 0.8 nm (corresponding to seven layers to single layer) and the surface energy of the substrate underneath the FG nanosheets increases. On the basis of density function theory (DFT) calculations, the negative correlation of wear resistance to FG thickness and the positive correlation to substrate surface energy could be explained with the degree of interfacial charge transfer between FG and substrate which affects the strength of FG adhesion to the substrate.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
FUEL
·
2022
·
IF 8.035
Jian Wang,Yaofeng Mao,Jie Chen,ZiJian Li,Jun Wang,Fude Nie
Boron (B) shows great potential applications in the military and aerospace industry due to its high calorific value. However, the reactivity is limited by the inert oxide layer (B 2 O 3 ) that covers the B particles. Herein, nano-Al, and Fluorographene (FG) are employed as coating materials to enhance the ignition and combustion efficiency of boron. When graphite fluoride (GF) was utilized as an oxidizer (the B/GF mass ratio is 1:9), the maximum heat release of B@nano-Al/GF (∼5.6 kJ/g) and B@FG/GF (∼5.4 kJ/g) were markedly higher than that of raw B/GF (∼2.5 kJ/g), ascribed to the self-activation effect of the coating layer. On this basis, the combustion experiments were performed and their performances were compared and studied. Specifically, the ignition delay time of B@nano-Al/GF and B@FG/GF was decreased to 320 ms 262 ms, respectively, compared with that of raw B/GF (380 ms) with 15 W laser power. This is consistent with the ignition burning test, where the B@6%nano-Al/GF and B@2%FG/GF have higher flame height than raw B/GF. However, the maximum pressure and pressurization rate decreased for B@6%nano-Al/GF and B@2%FG/GF because of the reduced amount of gas caused by decreased boron content. Additionally, the effects of the B/GF mass ratio (1:9, 2:8, 3:7, 4:6) on the combustion performances of composites were fully studied. The pressure output, combustion reaction, and ignition delay time are reduced with B/GF mass ratios increased. This work could provide a general approach to improve the ignition and combustion performance of boron.
研究领域:
材料科学
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航空航天工程
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军事技术
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化学工程
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产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 47
·e53193
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IF 3.057
Xiuzhou Lin,Qiang Peng,Song Duan,Chunjiang Zhang,Xulei Chen,Zhiqiang Deng,Baojie Dou,Yingjun Zhang,Xiulei Gao,Zhiwen Fang
In this study, ZIF-8 modified fluorinated graphene composite (FG@ZIF-8) was innovatively prepared and used as a novel functional filler to improve the anticorrosion performance of epoxy coating on Q235 carbon steel. The morphology and structure of FG@ZIF-8 composites were characterized by scanning electron microscopy (SEM), x-ray powder diffractometer (XRD), Fourier transform infrared spectrometer (FT-IR), and x-ray photoelectron spectroscopy (XPS) tests. The results showed that the structure and morphology of the composites largely depended on the composition ratio of FG and ZIF-8. The mechanical properties and corrosion resistance of FG@ZIF-8 modified coatings were also investigated. The unique two-dimensional sheet structure and insulation of FG in the FG@ZIF-8 filler can not only inhibit the penetration of corrosive media but also discourage electron migration effectively on the interface of coating/matrix during the electrochemical reaction. Meanwhile, the chemical cross-linking between the amine groups in ZIF-8 and the epoxy group increases the degree of densification of the coatings. Besides, the 2-methylimidazole from the dissolution of ZIF-8 on FG@ZIF-8 will also inhibit the corrosion reaction. These advantages endow the FG@ZIF-8 modified epoxy coatings an excellent long-term corrosion resistance. Our findings may inspire the development of new graphene-based materials with superior protective properties for metallic materials.
研究领域:
材料科学
·
腐蚀与防护
✓ 已验证
产品关联
DOI
高影响因子
TRIBOLOGY INTERNATIONAL
·
2019
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IF 3.517
Xiaojing Ci,Wenjie Zhao,Jun Luo,Yangmin Wu,Tianhao Ge,Lu Shen,Xiulei Gao,Zhiwen Fang
Fluorographene could be used as lubricating additive which is attributed to its high mechanical strength and unique layered structures. However, it is difficult to disperse fluorographene uniformly in base oil due to its low surface energy. Here, we formulated multilayered fluorographene nanosheets (FG i ) by fluorinating graphene and then exfoliated the FG i using chloroform to obtain fluorographene (FG). Tribological results indicated that the coefficient of friction and the wear rate of GTL-8 nanolubricant oil enhanced with 0.3 mg/ml FG were decreased by 35% and 90%. Combining Transmission Electron Microscope images and X-ray photoelectron spectra, it is illustrated that physical transferred film and tribochemical film were generated which were beneficial for the excellent tribological performances of GTL-8 based oil enhanced via FG.
研究领域:
材料科学
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机械工程
✓ 已验证
产品关联
DOI
高影响因子
LANGMUIR
·
2024
·
IF 3.7
Ding Wang,Xiaohua Jia,Zhiqiang Shan,Li Gao,Jin Yang,Zhaofeng Wang,Haojie Song
Fluorinated graphene (FG) among numerous two-dimensional materials has enormous potential in improving antifriction properties. However, they being susceptible to thermal oxidation and prone to wear hinder practical applications. Herein, UIO-66-NH2 (Zr-MOF) enjoying good chemical and thermal stabilities was assembled on the surface of FG nanosheets under covalent bonds and van der Waals forces. The Zr-MOF@FG composite was successfully synthesized and used as a lubricant additive. It can be seen that Zr-MOF@FG composites offer a synergistic lubricant mechanism at the friction interface. Moreover, due to the adsorption and purification performance of Zr-MOF, the obtained Zr-MOF@FG composite adsorbs the abrasive rust during the friction process, thereby realizing the purification of the lubricant. These findings suggest that Zr-MOF@FG shows tremendous potential as a lubricant additive.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2023
·Vol. 140
·期 12
·e53637
·
IF 3
Xiuzhou Lin,Xulei Chen,Shixiong Zhao,Baojie Dou,Qiang Peng,Zhiqiang Deng,Wilfred Emori,Xiulei Gao,Zhiwen Fang
Fluorinated graphene (FG) is a derivative of graphene with excellent insulating properties, however, the dispersion performance of FG in organic coatings is still a challenge in anti-corrosion applications. This study aims to propose a simple strategy to effectively improve the dispersion of FG towards enhancing its interfacial compatibility with epoxy resins. FG was modified with amino-containing 3-aminopropyl triethoxysilane (APTES) and epoxy terminated 3-glycidoxypropyl trimethoxysilane (GPTMS). The chemical compositions and microstructures of FG and the silane-modified FGs were effectively characterized. Moreover, the corrosion resistance and anticorrosion mechanisms of the epoxy coatings modified by FG and silane-modified FG were systematically studied, and the results showed that the silane coupling agent effectively improved the dispersion of FG in the epoxy coating and enhanced the interface interaction between FG and the epoxy resin, thereby improving the barrier properties of the epoxy coating and preventing the penetration of the corrosive medium. Electrochemical and tribological analyses showed that the APTES-modified FG (AFG) coating exhibited better anti-corrosion properties than the GPTMS-modified FG (GFG) coating, which is attributed to the improvement of its crosslinking density and barrier properties by the reactions between the amino groups on AFG and the epoxy resin.
研究领域:
材料科学
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化学工程
·
腐蚀与防护
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Guolong Wang,Zhuofan Yang,Leyuan Li,Junwen Ren,Jiamei Liu,Lei Li
Modern electrical applications urgently need flexible polymer films with a high dielectric constant (εr) and low loss. Recently, the MXene-filled percolative composite has emerged as a potential material choice because of the promised high εr. Nevertheless, the typically accompanied high dielectric loss hinders its applications. Herein, a facile and effective surface modification strategy of cladding Ti3C2Tx MXene (T = F or O; FMX) with fluorographene (FG) via self-assembly is proposed. The obtained FMX@FG hybrid yields high εr (up to 108 @1 kHz) and low loss (loss tangent tan δ = 1.16 @ 1 kHz) in a ferroelectric polymer composite at a low loading level (the equivalent of 1.5 wt % FMX), which is superior to its counterparts in our work (e.g., FMX: εr = 104, tan δ = 10.71) and other studies. It is found that the FG layer outside FMX plays a critical role in both the high dielectric constant and low loss from experimental characterizations and finite element simulations. For one thing, FG with a high F/C ratio would induce a favorable structure of high β-phase crystallinity, extensive microcapacitor networks, and abundant interfacial dipoles in polymer composites that account for the high εr. For another, FG, as a highly insulating layer, can inhibit the formation of conductive networks and inter-FMX electron tunneling, which is responsible for conduction loss. The results demonstrate the potential of a self-assembled FMX@FG hybrid for high εr and low loss polymer composite films and offer a new strategy for designing advanced polymer composite dielectrics.
研究领域:
材料科学
·
电气工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2018
·
IF 6.735
Fan Lei,Meng Yang,Feng Jiang,He Zhang,Zhi Zhang,Dazhi Sun
Fluorographene (FG), as an important class of graphene derivatives, has shown great promise in high-performance devices and lubricating materials. However, the large-scale fabrication of high-quality and impurity-free FG nanosheets still remains a main challenge. Herein, a simple liquid-phase exfoliation approach to prepare thin FG nanosheets through the preliminary intercalation of raw graphite fluoride (GrF) particles by N,N-dimethyl formamide molecules, followed by a short-time microwave treatment is reported. Atom force microscopy measurements demonstrate that as-prepared FG nanosheets are comprised of no more than four monolayers after the microwave irradiation. After exfoliation, a small amount of aromatic C C groups in the FG nanosheets are restored, which slightly lowers the F content in FG as compared with the raw GrF. Besides, no other side reaction and impurity elements are introduced during the exfoliation process as revealed by X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. The resultant high-quality FG nanosheets exhibit excellent thermal stability and remarkable lubrication behavior in oil, and thus can be used as a new class of graphene derivatives with the capability of large-scale fabrication for the future device and various other applications.
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
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 6
·49801
·
IF 2.52
Fan Zhang,Jinhui Li,Tao Wang,Chao Huang,Fei Ji,Liang Shan,Guoping Zhang,Rong Sun,Ching-ping Wong
Low dielectric constant and low dissipation factor, superior hydrophobicity, excellent thermal and mechanical property, and good optical performance are desired for advanced electronic packaging of fan-out wafer level package (FO-WLP). An effective approach was introduced to fabricate novel fluorinated graphene/polyimide(FG/PI) nanocomposite films in this paper. FG nanosheets exhibit excellent dispersion in the PI matrix due to their high surface area with some oxygen-containing functional groups, and individual graphitized planar structure. Besides, the effects of the addition of FG on the dielectric, optical, mechanical, thermal properties as well as the hydrophobicity of the films are investigated with controlled amounts of FG. The dielectric constant and loss can be as low as 2.64 (at 10 6 Hz) and 0.00176 for PI-0.5wt% FG. And with the increase of the loading of FG, the thermal stability ( T 5 = 514°C) and mechanical property (tensile modulus = 2.11GPa, tensile strength = 93.23 MPa, elongation at break = 11.60%) has been improved successfully. Besides, the contact angles have been increased from 83° to 92° showing a superior hydrophobicity which is essential for the FO-WLP. Moreover, the incorporation of FG also proved excellent optical performance of 88% transmittance at 550 nm. Therefore, with the excellent comprehensive performance, the as-prepared FG/PI films possess widespread applications in the microelectronics especially in FO-WLP.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
THERMOCHIMICA ACTA
·
2021
·
IF 3.115
Baozhong Zhu,Siyi Zhang,Yunlan Sun,Yanwu Ji,Jinghui Wang
Two-phase flow loss is an important factor to reduce the combustion performance of aluminum-based solid propellants, which can be decreased if aluminum particles burn more rapidly and produce more gaseous products to crack their agglomeration. To reduce aluminum agglomeration and improve the combustion performance, fluorine-containing organic substances (FCOS) is used as a modified material for aluminum powder. Fluorinated graphene (FG) is a promising FCOS with both the physical and chemical properties of graphene and polytetrafluoroethylene, so we studied the effects of FG on the combustion and agglomeration of nano-aluminum powder. Specifically, the ignition, combustion, and agglomeration characteristics of FG modified nano-aluminum with ammonium perchlorate were studied. Results show that FG can promote the decomposition of ammonium perchlorate. An appropriate amount of FG has a positive effect on the ignition delay time and flame propagation velocity of nano-aluminum powder. The increase of FG content can reduce the size of aluminum agglomerates. These results can be useful for the applications of FG in aluminum-based solid propellants.
研究领域:
材料科学
·
燃烧与推进
✓ 已验证
产品关联
DOI
高影响因子
Analytical Methods
·
2017
·Vol. 9
·期 47
·6645-6652
·
IF 1.9
Fan Li,Weili Wei,Die Gao,Zhining Xia
This is the first report on the fabrication of oxidized fluorinated graphene sheets supported on silica (OFG@silica) for the selective adsorption of perfluorochemicals (PFCs). To increase the affinity towards PFCs, oxidized fluorinated graphene (OFG) was grafted onto amino-terminated alkyl chain modified silica (NH2-silica), thus producing a mixed-mode material combining fluorophilicity and hydrophobic affinity with anion-exchange properties. The adsorption behavior and mechanism of OFG@silica towards PFCs were explored using a solid phase extraction (SPE) method. For demonstration, several organic analytes including perfluorinated fatty acids (PFFAs), aromatic analytes and fatty acids (FAs) were employed as adsorbates. By analysing the physicochemical properties of analytes, we found that the adsorption amount of analytes was negatively correlated with their molecular acidity coefficient (pKa) and positively correlated with their octanol–water distribution coefficient (log D) at pH 7, suggesting that the anion-exchange effect and hydrophobic affinity played a major role in adsorption. Moreover, compared with FAs, PFFAs exhibited a higher adsorption amount which benefited from fluorous–fluorous interactions between PFFAs and OFG@silica. These findings suggested that OFG@silica might be a potential adsorbent for the enrichment of PFCs.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
ACTA ASTRONAUTICA
·
2024
·
IF 3.1
Huanhuan Gao,Hui Liu,Peihui Xu,Jianzhong Liu
The potential of the Al-F reaction in suppressing agglomeration during propellant combustion and enhancing combustion performance is investigated by introducing fluorinated graphene as a fluorinated oxidizer. Comparative analyses of ignition combustion and agglomeration behaviors are conducted on novel composite powders and propellant samples modified with varying contents of fluorinated graphene using laser and hot wire ignition visualization systems. Characterizing parameters such as characteristic spectra, flame grayscale, ignition delay time, combustion duration, and burning rate are measured during combustion at different pressures. Additionally, agglomerated particles are collected via quenching techniques under 7 MPa pressure to explore the influence mechanism of fluorinated graphene on agglomeration near the burning surface, and a comprehensive influence mechanism is proposed. Results indicate that fluorinated graphene promotes ammonium perchlorate decomposition, accelerates oxidizing gas release, and enhances thermal conduction at the burning surface. The reaction between Al and F decreases the formation of intermediates (AlO and Al 2 O), while the interaction of F with Al and Al 2 O 3 effectively inhibits the clustering of Al particles, replacing conventional oxidation reactions and resulting in a unique micro-explosion jetting phenomenon. The introduction of 15 % fluorinated graphene concentrates most product particles around 10 μm, enhancing energy release during combustion. Overall, this composite powder containing fluorinated graphene effectively improves the combustion performance of aluminum-containing composite propellants, inhibiting Al particle agglomeration and potentially reducing specific impulse loss in solid rocket motors.
研究领域:
材料科学
·
燃烧学
·
推进剂工程
✓ 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）