SYNTHETIC METALS
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2021
·
IF 3.266
Jiaoyan Shi,Lipeng Wu,Qingya Sun,Fan Wu,Aming Xie
Elemetal doping is an efficient strategy to adjust the microstructue and electronic property of a carbon material, as a result, shows great potential in the design of novel electromagnetic absorption (EMA) materials. In this work, we report an useful strategy to prepare a N,S co-doped carbon (NSC) using TTF-TCNQ as the precusor, and systematically explore its frequency-depedent dielectric and EMA properties. Different N/S ratios can be tuned by the regulation of pyrolitic temperature. The derived NSC exhibits wonderful EMA performance when the pyrolytic temperature is setted to 700 ℃ with loading ratio of 35 wt%. Efficient absorption can be achieved in the frequency range of 6.4–18 GHz. Moreover, it is determined that the efficient absorption bandwidth gets to 6.5 GHz, while the maximal absorption reaches −46 dB. The EMA mechanism of NSC is considered to be mainly contributed by improved impedance matching realized by macropores, enhanced conductance loss caused by well constructed condutive network, and polarization by N,S doping. This research provides a new idea for development of novel carbon materials for EMA applicaion.
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高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
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2019
·Vol. 38
·期 1
·17-23
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IF 2.804
Chi Wei-Wen,Zhang Rong-Yuan,Han Ting,Du Jian,Li Hong-Kun,Zhang Wei-Jie,Li Yong-Fang,Tang Ben Zhong
The copper-catalyzed and metal-free azide-alkyne click polymerizations have become efficient tools for polymer synthesis. However, the 1,3-dipolar polycycloadditions between internal alkynes and azides are rarely employed to construct functional polymers. Herein, the polycycloadditions of dibutynoate ( 1 ) and tetraphenylethene-containing diazides ( 2 ) were carried out at 100 °C for 12 h under solvent- and catalyst-free conditions, producing soluble poly(methyltriazolylcarboxylate)s (PMTCs) with high molecular weights in high yields. The resultant polymers were thermally stable with 5% weight loss temperatures up to 377 °C. The PMTCs showed aggregation-induced emission (AIE) properties. They could work as fluorescent sensors for detecting explosive with high sensitivity, and generate two-dimensional fluorescent photopatterns with high resolution. Furthermore, their triazolium salts could be utilized for cell-imaging applications.
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高影响因子
MACROMOLECULAR RESEARCH
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2019
·Vol. 28
·期 5
·450-454
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IF 1.758
Gu Yiyang,Zhao Zhen,Chao Danming,Liu Xincai
Stimuli-response materials have attracted considerable attention due to their potential applications in sensoring, smart coatings, and intelligent devices. Herein a novel thermo-photo staged response shape memory poly(aryl ether ketone) bearing flexible alkyl segments and azobenzene groups was successfully designed and synthesized. Its chemical structure, thermostability and mechanical properties were characterized through Fourier Transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, thermal gravimetric analysis and dynamic mechanical analysis. The resultant polymer disclosed thermo-/photo-dual stimuli-response behaviors, ascribed to its unique chemical structure. Firstly, the polymer film exhibited good thermal response shape memory effect with satisfied shape fixity ratio ( R f ) and shape recovery ratio ( R r ) (>99%). Moreover, an interesting photo-thermo two-staged responsive shape memory behavior with bending deformation over 100° upon the exposure of ultraviolet light and recovering to its original state through thermal treatment was revealed, attributed to the transcis isomerization of azobenzene groups.
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高影响因子
Journal of Materials Chemistry B
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2019
·Vol. 7
·期 6
·1005-1016
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IF 5.047
Furong Cheng,Ting Su,Kui Luo,Yuji Pu,Bin He
Biodegradable and stimuli-responsive polymers have been widely explored due to their great potential in various biomedical applications. Here, biodegradable and oxidation-responsive poly(ester-thioether)s with different backbones were prepared by polymerization of dithiols and diacrylates. Two isomeric dithiol monomers, 2,3-dimercaptobutane (DMB) and 1,4-butanedithiol (BDT), were employed to synthesize poly(ester-thioether)s in the presence of 1,6-hexanediol diacrylate (HDA). The polymerization and oxidation kinetics of poly(ester-thioether)s were found to be controllable by tuning the polymer backbones, which were prepared using different monomers. The polymerization kinetics demonstrated that BDT showed a faster polymerization rate than DMB due to less steric hindrance. Poly(ester-thioether)s PHBD and PHDM, which were prepared from BDT and DMB with HDA, respectively, showed the fastest and slowest oxidation-responsiveness both in THF solution and in the form of polymer films. Finally, the potential application of poly(ester-thioether)s as drug vehicles for anticancer therapy was confirmed by using doxorubicin (DOX) as a model drug. The DOX-loaded micelle DOX/mPEG-PHBD showed much faster H2O2-responsive drug release and better anticancer efficacy in both MCF-7 and 4T1 cells due to the higher sensitivity of PHBD to H2O2.
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PubMed
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2019
·
IF 3.218
Yiqi Wei,Yinglin Yan,Yiming Zou,Mangmang Shi,Qijiu Deng,Nana Zhao,Juan Wang,Rong Yang,Yunhua Xu
Lithium-sulfur (Li-S) battery with high theoretical capacity (1675 mAh g −1 ) and energy density (2600 Wh kg −1 ) is principally considered as an attractive alternative for state of art Li-ion batteries. In this study, a series of ternary composites were synthesized with bamboo-derived hierarchical carbon (BDC) to load S and flexible polyaniline (PANI) as a coating layer. The BDC/S composite was encapsulated by different weight percentage of PANI. The ternary PANI@BDC/S composites were characterized detailly by structural and electrochemical analysis and the results revealed that the PANI@BDC/S-20% electrode presented a thin and uniform PANI coating. As a cathode material for Li-S battery, the PANI@BDC/S-20% electrode exhibited the highest initial capacity (1463 mAh g −1 at 0.1C), outstanding long-life performance (366 mAh g −1 at 0.5C after 500 cycles), excellent rate property (527 mAh g −1 at 2C). The incremented gains were mainly because thin PANI coating was polymerized along with the porous carbon walls of BDC substrate, leaving an excellent hierarchical porous microstructure. The specific structure showed great physical confinement for polysulfides , meantime, the polysulfide migration could be restricted by heteroatom (N atom) doped on the PANI backbone. The soft and stable PANI shell reduce volume expansion during cycles, providing an integrated conductive framework for enhancing the electrochemical contact between S particles and carbon substrate. More important, the modified polar interface contributed to stable SEI formation. Such a novel design of cathode material demonstrated great potential for practical applications in Li-S batteries.
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高影响因子
HIGH PERFORMANCE POLYMERS
·
2019
·
IF 1.584
Yayun Zheng,Xing Yang,Meng Yuan,Jujie Luo
Two novel gas separation membranes (Phenyl(Ph)-poly(ether ether ketone)s (PEEKs) and PEEKs) based on PEEKs with a high fractional free volume were designed and synthesized. The structure and thermodynamic stability of the membranes were investigated using Fourier transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy, and thermogravimetric analysis. The two membranes, which were determined to be high-molecular weight polymers by gel permeation chromatography, showed good solubility in a weakly polar solvent. The gas transport properties of the Ph-PEEK membranes were investigated for different gases (CO2, O2, CH4, and N2) at 25°C and 1 atm. The Ph-PEEK-3 membrane with the largest free volume had the largest gas permeability coefficient and maintained good selectivity. The effect of operating temperature on the gas permeation of the Ph-PEEK-3 membrane was also investigated, and the maximum permeability of the four single gases was reached at 55°C and 1 atm.
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高影响因子
COLORATION TECHNOLOGY
·
2019
·Vol. 135
·期 5
·335-348
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IF 1.241
Qiushui Zhang,Wei Xiong,Shufen Zhang,Wei Ma,Bingtao Tang
A new kind of hetero-bifunctional reactive dye containing 2-ethoxy-4-chloro- s -triazine, with better activity matching with β-hydroxyethyl sulphone sulphate at a low fixation temperature, was successfully synthesised and characterised. An ethoxy group was designed to be introduced into triazine to increase the substantivity and the reactivity of the dyes. Thereby, the fixation of mono- s -chlorotriazine/hydroxyethyl sulphone sulphate (KM-type) bifunctional reactive dyes on cotton was improved, and dyeing under mild conditions with high fixation was realised. Nineteen dyes with orange, red and blue colours were synthesised and characterised by UV-Vis and infrared spectroscopy and mass spectrometry. Synthesised dyes were dyed at 60, 75 and 90°C, respectively. Exhaustion and reactivity for all of the ethoxy-containing KM-type dyes was over 90% at the optimal temperature, and fixation was over 87%, which was higher than the ethoxy-free comparative dyes. The optimal fixation temperature of ethoxy-containing dyes was initially reduced to 75°C, and then to 60°C. Compared with comparative dyes, the wash fastness and light fastness were basically unchanged, and the wet rub fastness of the H-acid series was reduced by one grade.
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高影响因子
Materials Today Communications
·
2019
·
IF 1.859
Xunan Shen,Chao Zhang,Yang Feng,Wei Li,Guifeng Chen,Chengchun Tang
In this work, Cu 2 ZnSn(S,Se) 4 thin films were prepared by sol-gel methods based on dimethyl sulfoxide solutions with H 3 BO 3 additive. The morphological, structural, compositional and photovoltaic properties of the Cu 2 ZnSn(S,Se) 4 thin films were investigated. We found that the formation of voids, cracks and fine-grain layers were suppressed effectively with slight H 3 BO 3 . Based on the decrease of these micro defects, the series resistance decreased and shunt resistance increased largely. And the band gap of CZTSSe solar cells broaden from 1.031 eV to 1.064 eV. The best solar cell showed an open-circuit voltage of 440.1 mV, short-circuit current density of 28.15 mA/cm 2 , fill factor of 58.81% and power conversion efficiency of 7.27% under air mass 1.5 (100 mW/cm 2 ) illumination.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2019
·Vol. 137
·期 26
·48830
·
IF 2.188
Gang Wang,Fei Wang,Anfeng Li,Miaomiao Zhang,Jie Zhang,Jinwei Chen,Ruilin Wang
The SPEEK/s-TiO 2 composite membrane was prepared by blending sulfonated poly(ether ether ketone) (SPEEK) and sulfonated titanium dioxide (s-TiO 2 ) nanoparticles. The important physiochemical parameters such as proton conductivity, water uptake, swelling degree and ion exchange capacity of the composite membrane were measured. The thermal stability and chemical stability were also tested. It was observed that the SPEEK/s-TiO 2 composite membrane exhibited the best selectivity (7.13 × 10 4 S·min·cm −3 ) accompanying high proton conductivity (0.061 S·cm −1 ) and low tetravalent vanadium ion (VO 2+ ) permeability (8.55 × 10 −7 cm 2 ·min −1 ) compared with Nafion117, SPEEK and SPEEK/TiO 2 membranes. The battery performance with these membranes was characterized by charge–discharge cycling tests and it was found that the SPEEK/s-TiO 2 composite membrane showed the highest energy efficiency (EE) up to 82.3%, indicating the SPEEK/s-TiO 2 composite membrane is a candidate for vanadium redox flow battery (VRFB) application. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137 , 48830.
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高影响因子
POLYMER
·
2018
·
IF 3.483
Cuihong Jin,Xiuling Zhu,Shuai Zhang,Shuai Li
In this work, a series of long flexible alkylsulfonated side chains poly (phthalazinone ether ketone) (SFG-PPEK-x) are successfully synthesized through polycondensation , demethylation , and sulfobutylation grafting reaction to the polymer backbone. The resulting ionomers could dissolve in polar aprotic solvents , such as DMSO , NMP etc and show excellent film-forming properties. Furthermore, the effect of side chain lengths on the properties of the resulting PEMs, such as proton conductivity, water uptake, and swelling ratio are investigated systematically. The SFG-PPEK-4 membranes (IEC = 1.70 mmol g −1 ) show the highest proton conductivity in the range of 107 mS cm −1 at 30 °C and 184 mS cm −1 at 80 °C, which is higher than that of Nafion ® 115. The thermal, mechanical properties and chemical stability of SFG-PPEK-x are discussed, systematically.
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高影响因子
ELECTROCHIMICA ACTA
·
2018
·
IF 5.116
Mingquan Liu,Silu Huo,Min Xu,Linlin Wu,Mingjie Liu,Yifei Xue,Yi-Ming Yan
Nitrogen and sulfur co-doped carbon (NSC) is considered as a promising electrode material for supercapacitors (SCs). However, the specific capacitance and the rate performance of NSC are not satisfied for practical applications due to its inappropriate structural properties. Herein, we report the structural engineering of NSC by optimizing pore structure to obtain an ordered hierarchical pore network. The as-prepared NSC possesses a high gravimetric capacitance of 322 F g -1 at the current density of 1.0 A g −1 and retains 206 F g −1 (64% of its capacitance at 1.0 A g −1 ) at the high current density of 100 A g −1 . Moreover, it reveals an excellent cycling performance with ∼93.4% capacitance retention after 10000 cycles at the current density of 20 A g −1 . An assembled symmetric supercapacitor (SC) shows a remarkable energy density of 11.4 Wh kg −1 and a high power density of 12.9 kW kg −1 . The outstanding performances of NSC electrodes benefit from the efficient ion diffusion and fast charge transfer. This work paves a way to rationally design and engineer the structure of NSC for achieving both high rate capability and high specific capacitance for SCs applications.
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高影响因子
SYNTHETIC METALS
·
2018
·
IF 2.526
Junlong Niu,Liangmei Rao,Ping Liu,Wenwen Zhang,Wenna Zhang,Yinxiu Zuo,Keke Chai,Shuai Chen,Jingkun Xu,Xuemin Duan
Two novel chiral 3,4-dihydro-2 H -thieno[3,4- b ][1,4]dioxepine (ProDOT)-based electrochemical sensor , employing a pair of glassy carbon electrodes modified with chiral poly(2-Phenyl-propionic acid 3,4-dihydro-2 H -thieno[3,4- b ][1,4]dioxepin-3-ylmethyl ester) (PProDTM-PP), were utilized for the enantioselective detection of chiral 3,4-dihydroxyphenylalanine (DOPA). The enantioselective recognition between chiral PProDTM-PP modified glassy carbon electrodes and chiral DOPA was studied by using different electrochemical technologies. The redox activity and electrochemical stability of chiral PProDTM-PP was good. ( R )-PProDTM-PP and ( S )-PProDTM-PP showed higher peak current responses toward D -DOPA and L -DOPA, respectively. Furthermore, the recognition efficiencies of chiral PProDTM-PP are between 1.48 and 1.89, which is higher than chiral PEDOT-based electrochemical sensors (around 1.10). The chiral PProDTM-PP provides an alternative to chiral recognition.
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高影响因子
危险品化学品经营许可证（带存储）