Energy Storage Materials
·
2024
·
IF 18.9
Wenxia Sima,Yuxiang Mai,Potao Sun,Ming Yang,Tao Yuan,Binghao Chen,Yuhang Yang
Polyimide, endowed with high thermal resistance due to its aromatic structure, is considered a potential candidate for high-temperature polymer dielectrics. However, the strong electron delocalization in the aromatic structure causes significant leakage current during high-temperature electron transport, impairing energy storage performance. This contradictory relationship presents a bottleneck in enhancing the high-temperature energy storage performance of PI. In this work, inspired by fish migration influenced by vortices, we propose inducing electron displacement through fluorine-modified aromatic structures, constructing an internal electric field in PI to affect electron transport. This approach cleverly resolves the conflict between thermal resistance and current loss caused by the aromatic main chain in PI, achieving a synergistic enhancement of thermal resistance and high-temperature energy storage performance. Experimental results show significant improvements in both the high heat-resistant quality and high-temperature energy storage performance of PI. The glass transition temperature increased from 257.32 °C to 264.07 °C, and the leakage current density decreased from 7.1 × 10 –7 A/cm 2 to 2.8 × 10 –8 A/cm². Simultaneously, with a charge-discharge efficiency of approximately 90 %, the discharge energy density increased from 0.36 J/cm 3 to 5.22 J/cm 3 , an improvement of 1345.98 %. This strategy validates the potential of aromatic structures as the main chain for high-temperature energy storage polymers.
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Xiaoli Fan,Xin Song,Jingxue Sun,Yangpeng Zhang,Zhonghua Li
Covalent-organic frameworks (COFs), characterized by their exceptional light absorption and ordered architecture, have emerged as potential candidates for photocatalytic hydrogen production. In this work, we discovered that the incorporation of fluorine into the sub-nanocavity of azine-linked COF (TF-COF) not only augments its hydrophobicity but also strengthens the interaction between Pt cocatalysts and COFs. In an effort to enhance photocatalytic water splitting efficiency, we integrated the hydrophobic TF-COF with the hydrophilic carbon nitride (CN) to construct a hydrophilic/hydrophobic heterojunction (CTF-x heterojunction). Both experimental results and density functional theory (DFT) calculations reveal that the hydrophilic side, CN, aids in the adsorption and transfer of water molecules, whereas the hydrophobic side, TF-COF, generates hydrogen and promotes its overflow, thereby achieving space charge separation. The hydrogen evolution activity of CTF-50 % (with a CN content of 50 %) reached an optimal value of 2428 μmol g −1 h −1 , with an apparent quantum yield (AQY) of 2.6 % at 400 nm. This is approximately four times higher than that of pure CN and ten times greater than that of TF-COF. We believe this work will provide valuable insights for developing efficient heterojunction photocatalysts.
研究领域:
材料科学
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能源化学
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产品关联
DOI
PubMed
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2021
·
IF 5.455
Xiaomei Miao,Keyu Mao,Yue Yan,Yongbing Pei,Michael J. Sailor,Lianbin Wu
Porous silicon was widely used in displays, optical sensors , and biological imaging due to its high surface areas, adjustable microstructure, large adsorption capacity and excellent optical performance. Unfortunately, there are numerous reactive silane groups on the freshly etched porous silicon surface, which are susceptible to oxidization in the air, thereby affecting the optical performance and stability of porous silicon. This study provides an efficient strategy of using photocatalytic reaction to graft dodecafluoroheptyl methacrylate to freshly prepared n-type porous silicon surface, thereby generating a fluorine-modified porous silicon with high stability and superhydrophobic surface. The structure and composition of porous silicon before and after modification were analyzed by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy-energy dispersive spectrometer (SEM-EDS) and X-ray photoelectron spectroscopy (XPS). The effects of UV light, reactant mass fraction and reaction time on the surface properties of porous silicon were studied by water contact angle (WCA) and photoluminescence (PL). The results indicated that the dodecafluoroheptyl methacrylate was successfully grafted onto n-type porous silicon surface by photocatalytic reaction. The superhydrophobic and luminescent porous silicon was prepared by reacting 40 min in a dichloride solution containing 10 wt% dodecafluoroheptyl methacrylate under UV light. The WCA of the fluorine-modified porous silicon surface could reach 153° and had good photoluminescence intensity. This modified porous silicon surface had great stability in alkaline and air environment. After treated with alkaline droplets for 30 min, the WCA of modified porous silicon could maintain above 150° and had good photoluminescence. And under room temperature within a week, the porous silicon surface still showed great hydrophobic properties and photoluminescence intensity. In addition, the modified porous silicon has different responsiveness to ethanol solutions of different concentrations, which could be applied to alcohol sensors and has great development prospects.
研究领域:
材料科学
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表面化学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2018
·
IF 4.439
Wei Lin,Kangchao Lu,Shijian Zhou,Jian Wang,Feihu Mu,Yun Wang,Yong Wu,Yan Kong
Excessive or deficient defects in graphitic carbon nitride (g-C 3 N 4 ) nanosheets are detrimental to their photocatalytic activities . In this work, the approach of fluorine-containing solvothermal treatment has been applied to remodel the defects in g-C 3 N 4 nanosheets (CNS). The fabrication process has been comprehensively investigated and the samples are characterized by various techniques. The results manifest that the solvothermal treatment declines the amount of defects, while the addition of fluorine stimulates the emergence of nitrogen vacancies for producing new active sites which makes the obtained fluorine modified CNS present excellent photocatalytic activities. The average rate of photocatalytic hydrogen evolution under visible light irradiation is 2607.4 μmol·h −1 ·g −1 , which is almost 13 and 1.3 times of bulk g-C 3 N 4 (BCN) and CNS, respectively, and the degradation rate of rhodamine B is about 3.4 and 1.9 times, respectively.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS LETTERS
·
2021
·Vol. 152
·期 5
·1495-1505
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IF 3.186
Zhang Yue,Wang Li,Ma Qingqing,Wang Nan,Pan Zhiyong
SBA-15 was modified via post-treatment with (NH 4 ) 2 SiF 6 and (NH 4 ) 3 AlF 6 solution (NSF-T and NAF-T) and applied as support of Pd catalysts for the hydrogenation of 2-ethyl-anthraquinone (EAQ). The characterization results revealed that F could be incorporated into the framework of SBA-15 by forming Si–F bond and the amount of F increased as the molar ratio of F in treating solution to Si species in SBA-15 (F/Si) increased from 0.1 to 0.4 for NSF-T and 0.3 to 0.6 for NAF-T. At the same F/Si, the incorporated amount of F was larger with NSF-T than with NAF-T, and the latter could simultaneously create acid sites in catalysts. The hydrophobicity of catalysts could be effectively improved by incorporating F into SBA-15 supports, which favored the catalytic performance. The catalyst on SBA-15 treated by NSF with F/Si of 0.3 exhibited the high initial activity (0.24 molH 2 ·gPd −1 ·min −1 ) and selectivity (95.5%). Graphic Abstract
研究领域:
催化化学
·
材料科学
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产品关联
DOI
高影响因子
Asia-Pacific Journal of Chemical Engineering
·
2025
·
IF 1.6
Xiaoxia Ma,Huijian Guo,Yujia Sui,Yun Li,Jilin Cao
Lactide, a key raw material for polylactic acid, is prone to hydrolysis during synthesis from lactic acid using zeolite beta, reducing yield. To address this issue, zeolite beta with hydrophobic pores was synthesized by template-free method with in situ silicon source modification by tetraethoxyfluorosilane (TEFS). The effect of TEFS addition on the morphology, acidity, and wettability of the synthesized zeolite beta was investigated. The modification with F groups increases the total acid amount and the strength of strong acid sites, especially the Brønsted acid sites; simultaneously, the hydrophobicity of pores was also improved. F group–modified zeolite beta achieved a lactide yield of 84%, significantly higher than the 70% yield of unmodified zeolite beta. This enhancement could be attributed to the increase in Brønsted acid sites and the improvement of the hydrophobic pore microenvironment. This could improve the catalytic reaction activity; additionally, the rapid removal of water from near acid sites could promote the forward movement of the reaction equilibrium and inhibit the hydrolysis of lactide. This work provides a new approach to improve the hydrophobicity of the pores of zeolites as solid acid catalysts, which is beneficial to the efficient production of lactide.
研究领域:
催化化学
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材料科学
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绿色化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2021
·
IF 6.165
Yanling Wang,Yongfei Li,Qian Wang,Lei Liang,Longhao Tang,Chuanbao Zhang,Jincheng Lan,Lingtao Meng,Baoyang Jiang
In gas condensate reservoirs, liquid condensation near the wellbore region can break gas well deliverability when the pressure drops lower than dew point . Gas-wetting alteration is one of the potential approaches to overcome the difficulty. However, gas production remains restricted because the wettability of the core surface can only be altered from original liquid-wetting to neutral gas-wetting by traditional methods. Herein, fluorine-modified nanocrystalline cellulose is developed to achieve super gas-wetting alteration, increasing the contact angles of brine and decane on core surface from 22° and 0 o to 153° and 142°, respectively. This product not only reduces the surface free energy from 68.41 mN/m to 0.35 mN/m but also increases the surface roughness from 68.23 nm to 154.51 nm. The capillary tube and imbibition experiments further confirm that the wettability of the core surface has been altered from strong liquid-wetting to super gas-wetting. This result indicates that the liquid is easier to peel from the core surface to improve the ability of transportation and distribution. Besides, after the super gas-wetting alteration, the required pressure for displacement is reduced and the core permeability is restored dramatically. Meanwhile, it has been proved that fluorine-modified cellulose is more suitable for unconventional low permeability reservoirs. This work also reveals the mechanism of super gas-wetting alteration in detail, which will expand the better application of the material in more oilfields and other mining engineering developments.
研究领域:
石油工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Materials Research Express
·
2022
·Vol. 9
·期 2
·026404
·
IF 2.025
Xiang Li,Hua Liu,Yingbing Zhang,Zuozhen Liu
The practical application of superhydrophobic coatings has been greatly restricted due to the complicated preparation and fragile hierarchical structures on the surface. In this study, we prepared a robust superhydrophobic coating with a double-layer structure via a low-cost and facile method, adhering the non-wettability layer composed of silica nanoparticles and fluorine-modified epoxy resin to a binder resin layer on aluminum. The fluorine-modified epoxy resin with low surface energy can fix the silica nanoparticles after curing and cross-link with the adhesive layer. When the SiO2 content in the surface layer is 40%, the water contact angle (WCA) of the coating is 162°, and the sliding angle (SA) is 2°. In the mechanical performance test, the durable coating can remain superhydrophobic even after 260 cycles of friction or 160 cycles of tape peeling. In addition, the superhydrophobic coating with self-cleaning and anti-fouling properties also has the performance of acid-base solution resistance. Hence, the combination of the rough layer and the adhesive layer makes the practical application of artificial superhydrophobic coatings possible.
研究领域:
材料科学
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表面工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2014
·Vol. 26
·期 2
·884-890
·
IF 1.966
Li Rui,Wang Yan-ze,Mao Zhi-yong,Wang Da-Jian
A remote phosphor coating by using Sr 3 (Al,Si)(O, F) 5 :Ce 3+ (SASF:Ce 3+ ) on glass substrate was prepared by a simple and convenient screen printing method. The crystalline phase and the distribution of SASF:Ce 3+ crystals in coating were investigated by XRD and SEM, respectively. The scattering light and absorption light properties of remote phosphor coating with different thicknesses were discussed through Lambert–Beer’s law. The relationship between luminous efficiency and absorption coefficient was demonstrated. White light emitting diode prototype fabricated with blue chip and the prepared patterned SASF:Ce 3+ remote phosphor in this work showed excellent performances, opening a cost-effective process to generate planar white light.
研究领域:
材料科学
·
光学工程
·
发光材料
·
固态照明
·
功能涂层
✓ 已验证
DOI
高影响因子
COLLOID JOURNAL
·
2025
·
IF 1.1
Zheqing Gong,Lijun Chen
Acrylate polymer latex and vinyl acetate-tert-carbonatepolymer latex have been widely used as waterborne coating polymers for many industrial applications. A large number of open literatures have reported on the preparation and modification of acrylate latex or vinyl acetate-tert-vinyl carbonate latex, which are synthesized with semi-continuous seeded or soap-free emulsion polymerization or other advanced emulsion polymerization technology. However, the fluorine modified BA/MMA/VAc/VeoVa10 quaternary cross-linked polymer latex has not been reported in the open literatures. In this study, butyl acrylate (BA), methyl methacrylate (MMA), vinyl acetate (VAc), tertiary vinyl carbonate (VeoVa10) are the main monomers, and sulfosuccinateethoxyether alkyl monoester disodium salt (X-40) and alkylphenolpolyoxyethylene ether (LB-407) are used as the emulsifiers. Hydroxypropylmethacrylate (HPMA) and hexafluorobutyl methacrylate (HFMA) are used as the modified monomers. Potassium persulfate (KPS) is the initiator. The fluorine modified polymer latex is prepared via the semi-continuous seeded emulsion polymerization. The structure of the latex film is characterized by Fourier transform infrared spectroscopy (FTIR). Latex films are tested by the thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and contact angle (CA). The particle size of the latex is measured with the Zetatrac dynamic light scattering instrument. The conditions for preparing the resultant latex is optimized and obtained as follows: the amount of emulsifier is 7 wt %; the amount of initiator is 0.8 wt %; the amount of HFMA is 5 wt %. The appearance of the resultant latex is translucent and blue and the average particle size of the polymer latex and its distribution are small, which is 57.89 nm and 0.048, respectively. The water contact angle increased to 95.45°. Thermal decomposition temperature of the film of the fluorine modified polymer latex is 17.33°C higher than that of the film of conventional polymer latex.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2017
·Vol. 5
·期 31
·16162-16170
·
IF 8.867
Yajuan Hao,Xuan Jiao,Houbing Zou,Hengquan Yang,Jian Liu
The structure of biological components such as enzymes with active centers buried in hydrophobic pockets has inspired the design of new nanoreactors for efficient chemical processes. To address the current limitations of conventional hydrophobic catalysts or hydrophilic ones, herein, we reported the synthesis of core–shell structured catalysts with Pd-loaded fluoro-modified silica spheres as hydrophobic cores and mesoporous silicas as hydrophilic shells. The resultant nanoreactors allow the catalyst to not only be well dispersed in water but also be able to adsorb hydrophobic reactants to its active centers from water, which makes the catalyst exhibit much higher activity than its analogous catalyst Pd/SiO2 in the aqueous hydrogenation of olefins. Moreover, at the end of the reaction, we demonstrated that this nanoreactor can be directly used for the next reaction cycle after the removal of the upper layer of the organic product, making in situ catalyst recycling possible. Such a process significantly decreases the loss of the catalyst during recycling, which is unattainable for conventional catalyst separation methods such as filtration and centrifugation. After 12 reaction cycles, its activity has no significant decrease. These results illustrate the preparation of efficient solid catalysts for innovative green and sustainable chemical processes.
研究领域:
化学工程
·
材料科学
·
催化反应
✓ 已验证
产品关联
DOI
高影响因子
ADVANCES IN POLYMER TECHNOLOGY
·
2017
·Vol. 37
·期 6
·2152-2157
·
IF 1.291
Xiuming Wang,Tingting Xu,Cuifeng Zhang,Lijun Chen
The novel modified acrylate colloid was synthesized by semi-continuous seeded emulsion polymerization which was initiated with potassium persulfate (KPS), and octylphenol polyoxyethylene ether (OP-10) and sodium dodecyl benzene sulfonate (SDBS) were used as surfactants. Butyl acrylate (BA) and methyl methacrylate (MMA) were used as the main monomers and hexafluorobutyl methacrylate (HFMA, C 8 H 8 F 6 O 2 ), and benzyl methacrylate (BZMA, C 11 H 12 O 2 ) were used as functional monomers. Factors such as the amount of initiator, mass ratio of SDBD to OP-10 and monomers, which have an influence on particle size and morphology of the resultant colloid, are studied. Chemical composition of the modified acrylate colloid was evaluated by Fourier transform infrared spectrometry (FTIR). The thermal performances were characterized by differential scanning calorimetry (DSC) and thermogravimetry (TG). Furthermore, surface hydrophobicity of the latex film was examined by measurement of water absorption and water contact angle. Results indicate that the modified acrylate colloid has highest monomer conversion rate and lowest coagulation percentage when the mass fraction of emulsifier was 4% and mass ratio of SDBS to OP-10 was 1:2, mass fraction of initiator was 0.3%, mass percent of HFMA was 6%, and the amount of BZMA was 2%. Benzene ring-containing monomer is effectively participated in the reaction and has improved the thermal performance and surface properties of copolymer colloid. The resultant colloid has excellent hydrophobicity and low surface energy. Solid content of the resultant colloid was about 30% (wt %).
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
危险品化学品经营许可证（带存储）