Frontiers of Chemical Science and Engineering
·
2021
·Vol. 15
·期 5
·1312-1321
·
IF 4.204
Wang Wei,Lv Haijun,Du Juan,Chen Aibing
In this present work, N-doped carbon nanobelts (N-CNBs) were prepared by a confined-pyrolysis approach and the N-CNBs were derived from a polypyrrole (Ppy) tube coated with a compact silica layer. The silica layer provided a confined space for the Ppy pyrolysis, thereby hindering the rapid overflow of pyrolysis gas, which is the activator for the formation of carbonaceous materials. At the same time, the confined environment can activate the carbon shell to create a thin wall and strip the carbon tube into belt morphology. This process of confined pyrolysis realizes self-activation during the pyrolysis of Ppy to obtain the carbon nanobelts without adding any additional activator, which reduces pollution and preparation cost. In addition, this approach is simple to operate and avoids the disadvantages of other methods that consume time and materials. The as-prepared N-CNB shows cross-linked nanobelt morphology and a rich porous structure with a large specific surface area. As supercapacitor electrode materials, the N-CNB can present abundant active sites, and exhibits a specific capacitance of 246 F·g −1 , and excellent ability with 95.44% retention after 10000 cycles. This indicates that the N-CNB is an ideal candidate as a supercapacitor electrode material.
✓ 已验证
DOI
高影响因子
MACROMOLECULAR RESEARCH
·
2020
·Vol. 28
·期 5
·494-500
·
IF 2.047
Guo Xichao,Xiong Xuhai,Ren Rong,Chen Ping
In Part I of the paper, we have focused on the synthesis, characterization and solubility of three chain-extended bismaleimides containing aryl-ether-imide and phthalide cardo skeleton with different molecular weight (MPEIBMI-2.0, MPEIBMI-1.5 and MPEIBMI-1.25) and the thermal stability and thermal mechanical properties of their cured resins. In Part II of the paper, their high-temperature static viscoelasticity, shape memory (SM) performance and self-repairing behavior for micro-damages were investigated by dynamic mechanical analyzer and optical microscope. The creep test results exhibit the MPEIBMI-2.0 cured film has the strongest creep resistance at the same testing temperature due to the highest stiffness of its network structure, and the maximum allowable load of MPEIBMI-1.25 film at 200 °C reaches 15 MPa for 60 min creep experiment. The rate of stress relaxation for MPEIBMI-1.25 film is slower in spite of having relatively lower stress level. The MPEIBMI-1.25 film has the largest ultimate elongation at high temperature and this deformability confers it excellent shape memory (SM) ability. The shape fixity ratio reaches above 98% and the recovery rate is increased to above 96% from 94.5% after one SM cycle. The micro-damages on the surface of cured films could be repaired when heated to the temperature above their glass transition temperature, and the repairing temperature is increased with their crosslinking density to obtain perfect repairing efficiency.
✓ 已验证
DOI
高影响因子
Frontiers of Materials Science
·
2021
·Vol. 15
·期 2
·266-279
·
IF 2.765
Wang Nannan,Zheng Youbin,Feng Yange,Zhang Liqiang,Feng Min,Li Xiaojuan,Wang Daoai
Adsorption of drug powder is caused by triboelectrification on the surface of starch capsule during filling process. Furthermore, high wear rate and poor water lubricity also hinder the further practical applications of traditional starch capsule. To solve these problems, a glycerol-modified starch capsule with perfect anti-triboelectrification and enhanced lubrication performance was fabricated. Hydrogen bond between glycerol and starch molecules could reduce the bound water content on the capsule surface and thus realizes anti-triboelectrification. By adding glycerol, a three-tier structure composed of starch-glycerol-water is formed through hydrogen bonding on the surface of the starch film, which has been proven to be favorable for lubrication performance. When 5% glycerol is added, the short-circuit current ( I sc ) of starch-based triboelectric nanogenerator (TENG) is reduced by 86%, and the wear volume of the starch film is reduced by 89%. Under water lubrication condition, the lubrication performance of the starch-glycerol film can reach the super lubricated level with a friction coefficient of about 0.005. This work provides a new route to obtain modified starch capsules with improved anti-triboelectrification property, reduced wear rate and superlubricity property.
✓ 已验证
DOI
高影响因子
Frontiers of Materials Science
·
2020
·Vol. 14
·期 3
·332-340
·
IF 1.747
Wang Wei,Gong Jinhui,Guo Siyu,Jiang Lin,Liu Shaochao,Wang Li
Low-dimensional halide perovskites (HPs) have received considerable attention in recent years due to their novel physical properties such as compositional flexibility, high quantum yield, quantum size effects and superior charge transport. Here we show room temperature solution synthesis of 1D organic-inorganic lead bromide perovskite microwires (MWs). Our method uses acetone as a reactant, and when CH 3 NH 3 PbBr 3 is immersed, acetone reacts with CH 3 NH 3 + cations in the CH 3 NH 3 PbBr 3 single crystal by the dehydration condensation. The reaction generates a large (CH 3 ) 2 C = NHCH 3 + A-site which cannot be accommodated by the cuboctahedron formed by the corner-sharing [PbBr 6 ] 4− octahedral, leading to the transition of corner-sharing octahedra to face-sharing triangular prism and the crystal structure transformation from 3D to 1D. The formation process of (CH 3 ) 2 C = NHCH 3 PbBr 3 MWs does not involve any ligands, templates or catalysts. A two-terminal memory device was constructed using the (CH 3 ) 2 C = NHCH 3 PbBr 3 MWs, showing great potential of the method in fabrication of electronic and optoelectronic devices.
✓ 已验证
DOI
高影响因子
CELLULOSE
·
2020
·Vol. 27
·期 12
·6897-6908
·
IF 4.21
Guo Weihao,Zuo Minghui,Zhao Jian,Li Chao,Xu Qiaoliang,Xu Chunzhao,Wu Hongfeng,Sun Zhizhong,Chu Wenyi
A series of Brønsted–Lewis acidic di-cationic ionic liquids ( BLAILs ) were synthesized and the catalytic properties of glucose conversion to 5-hydroxymethylfurfural (5-HMF) were investigated. The experimental results showed that the ionic liquid with aluminum trichloride as Lewis acid anion ( BLAIL - 5 ) exhibited good catalytic performance. Under the best reaction conditions, the yield of the glucose conversion into 5-HMF and 5-EMF were 71% and 66%, respectively. In addition, the yield of cellulose to 5-HMF is 41%. The optimized catalytic system could be reused for 5 times without significant catalytic performance loss. In addition, the mechanism of BLAIL - 5 promoting glucose conversion to 5-HMF was studied by density functional theory calculation (DFT).
✓ 已验证
DOI
高影响因子
Science China-Chemistry
·
2022
·Vol. 65
·期 3
·521-531
·
IF 10.138
Chen Zhida,Chen Wenda,Zheng Lirong,Huang Tao,Hu Jing,Lei Yaqi,Yuan Qi,Ren Xiangzhong,Li Yongliang,Zhang Lei,Huang Shaoluan,Ye Shenghua,Zhang Qianling,Ouyang Xiaoping,Sun Xueliang,Liu Jianhong
In this study, the morphological distribution of Ru on nitrogen-doped graphene (NG) could be rationally regulated via modulating the combination mode between Ru precursor and the zeolite imidazolate framework-8 (ZIF-8). The cation exchange and host-guest strategies respectively resulted in two different combination modes between Ru precursor and ZIF-8 anchored on graphene. Following pyrolysis of the above precursors, Ru single-atom sites (SASs) with and without Ru nanoparticles (NPs) were formed selectively on NG (denoted as Ru SASs+NPs/NG and Ru SASs/NG, respectively). Ru SASs+NPs/NG exhibited excellent hydrogen evolution reaction (HER) performance in alkaline solutions ( η 10 =12 mV, 12.57 A mg −1 Ru at 100 mV), which is much better than Ru SASs/NG. The experimental and theoretical study revealed that Ru SASs could adsorb hydrogen with optimal adsorption strength, while Ru NPs could lower the barrier of water molecule dissociation, and thus Ru SASs and Ru NPs could synergistically promote the catalytic performance of HER in alkaline solutions.
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2020
·Vol. 56
·期 4
·3623-3637
·
IF 3.553
Ning Lijian,Yuan Li,Liang Guozheng,Gu Aijuan
It is still a great challenge to endow remoldable triple-shape memory thermosets (Rtri-SMTs) with high glass transition temperature ( T g ) and high mechanical properties. Herein, two Rtri-SMTs with high T g and high tensile properties, coded as BA1 and BA2, were developed through building unique dynamic crosslinked networks based on bismaleimide and novel bisallyl compounds with dynamic ester bonds (AEG1 and AEG2). The T g values of BA1 and BA2 resins are 143 °C and 203 °C, respectively, much higher than those of Rtri-SMTs reported so far (10–110 °C); meanwhile, BA resins exhibit high tensile strengths (BA1: 81 MPa; BA2: 84 MPa) and moduli (BA1: 2165 MPa; BA2: 3233 MPa), which are severally at least about 1.3–1.4 and 3.2–4.7 times of those Rtri-SMTs in the literature, respectively. Besides the superiorly high thermal and tensile properties, both BA resins are able to be remolded and reconfigured through the re-arrangement of crosslinked networks induced by dynamic exchange reaction of ester bonds. The mechanism behind these attractive properties of BA1 and BA2 resins is discussed. Graphical abstract Remoldable triple-shape memory thermosets with high glass transition temperature, high mechanical properties and good reconfigurability were developed.
✓ 已验证
DOI
高影响因子
Journal of Bionic Engineering
·
2021
·Vol. 18
·期 3
·548-558
·
IF 2.682
Jamil Muhammad Imran,Wang Qiongyan,Ali Amjad,Hussain Munir,Aziz Tariq,Zhan Xiaoli,Zhang Qinghua
Ice accumulation is a safety and operational threat in power lines, wind turbines, and transportations. Surfaces having both passive anti-icing and active deicing functionalities are very rare. Here, we report a self-cleaning slippery photothermal trap, which is icephobic passively and deice the surfaces actively by converting sun light to heat at the ice-substrate interface. The photothermal trap consists of three layers: a candle soot layer act as solar radiation absorber, a magnetic iron oxide Fe 3 O 4 nanoparticles layer act as heat spreader for lateral dispersal of sun light, and Room Temperature Vulcanized (RTV) insulation to reduce the transverse heat loss. Upon illumination under microsolar 300, the temperature of the surface increased by 40 °C within 200 s. The heat confinement at the magnetic Fe 3 O 4 nanoparticles layer leads to rapid increase of the surface temperature, ice start to melt and silicone lubricant facilitates the ice removal. The slippery photothermal trap removed the frozen droplet (10 µL) within 40 s upon the illumination of sun light and the frozen droplet was completely converted into water after 7 min illumination of solar light at −20 °C. The developed slippery photothermal trap also melted the fully frost covered layer within 100 s at −20 °C under sunlamp. The average defrosted length (25 mm) was also observed by irradiation of laser light for 45 s. The self-cleaning slippery photothermal coating showed outstanding deicing performance at subzero temperature for long term due to the infusion of silicone oil into the nanostructures and same chemical composition with binder.
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2022
·Vol. 57
·期 33
·16064-16079
·
IF 4.682
Zhang Yang,He Jiyu,Yang Rongjie
A series of novel tetraamino phthalocyanine zinc (TAPcZn) micro-crosslinked polyimide films were successfully synthesized by the copolymerization of 3,3′,4,4′-benzophenone tetracarboxylic dianhydride and 4,4′-oxydianiline. The UV–Vis, FTIR, NMR, MALDI-TOF-MS, and SEM–EDS technologies were used to demonstrate the synthesis of TAPcZn. The copolyimide films were mainly characterized via their morphologies, thermal stability, and mechanical properties. As expected, the copolyimide films inherited the optical properties of phthalocyanine compounds and showed good mechanical properties, excellent thermal stability, and flame retardancy with low content of TAPcZn (< 5.0 wt%), regularly. Smooth, uniform, and defect-free copolyimide films all showed good mechanical properties, and the tensile strength of PI with 1.52 wt% of TAPcZn reached 116.9 MPa, which is 19.7% higher than that of pure PI. In addition, as the amount of TAPcZn increases, both the residue char and the initial decomposition temperature of the copolymer film improved significantly, and the fire resistance of PI showed the same rules according to the limiting oxygen index and UL-94 tests. Amazingly, the obtained copolyimides are π -conjugate macrocycle homogeneous copolymers with excellent low dielectric properties. In particular, the 4.49 wt% TAPcZn/PI film showed an ultra-low dielectric constant of 2.326 (at 1 MHz) and a dielectric loss of less than 0.007. Therefore, the copolyimide films containing TAPcZn are highly prospective candidates as high-performance flexible substrates and dielectrics for electronics devices. Graphical Abstract
✓ 已验证
DOI
高影响因子
FIBERS AND POLYMERS
·
2016
·Vol. 17
·期 2
·194-198
·
IF 1.022
Xing Guiying
Aminated polyacrylonitrile (PAN-NH) nanofiber mats prepared by electrospinning and then aminated by multiamines with different chemical structures have been used for the immobilization of palladium. The PAN-NH fiber morphologies were characterized by scanning electron microscopy (SEM) and the dispersion of palladium particles on the PAN-NH fiber were examined by transmission electron microscopy (TEM). The catalytic activity and recyclability of the prepared heterogeneous palladium catalysts have been evaluated by the Heck reaction of iodobenzene with n -butyl acrylate. It was found that the catalytic activities of PAN-NH-Pd catalysts could be correlated with the chelating energies of the PAN-NH fiber mats with Pd active species.
✓ 已验证
DOI
高影响因子
JOURNAL OF POLYMER RESEARCH
·
2017
·Vol. 24
·期 5
·1-9
·
IF 1.615
Xue Sheng,Yang Haicun,Ma Wenzhong,Gong Fanghong,Tao Guoliang,Liu Chunlin,Pan Ji
Poly(methyl methacrylate) brushes grafted from attapulgite nanoparticles (ATP@PMMA) were prepared by R-Supported reversible addition-fragmentation chain transfer polymerization (RAFT). ATP was firstly activated, and allowed to react with γ-aminopropyltriethoxysilane (APTES), 4,4′-azobis(4-cyanovaleric acid) (ACVA) and bis(thiobenzoyl) disulfide stepwise to afford 4-cyanopentanoic acid dithiobenzoate functionalized ATP (ATP-CPADB). Then, RAFT polymerizations of MMA mediated by the different systems were conducted and compared systemically. The grafting process was verified by FTIR, XRD, XPS, TGA and TEM data. Kinetic behavior indicated that the anchored CPADB is more effective before diffusing into the bulk phase. The grafting ratio ( G
r ), while M
n of grafted and free polymer increased linearly with increasing monomer conversion in presence of free CPADB, giving the hybrid particles with more homogeneous distribution of grafted polymer layer.
✓ 已验证
DOI
高影响因子
Advanced Fiber Materials
·
2019
·Vol. 1
·期 3
·222-230
·
IF 0
Liang Liping,Dong Yanyan,Wang Hongfang,Meng Xu
Stimuli-responsive materials with switchable wettability have promising practical applications in oil/water separation. A novel CO 2 -responsive cotton fabric for controlled oil/water separation was fabricated based on mussel-inspired reaction and polymerized with 2-(dimethylamino)ethyl methacrylate (DMAEMA). As expected, the modified fabric exhibited switchable hydrophilicity and hydrophobicity after CO 2 /N 2 alternation, and it could be used for gravity-driven CO 2 -controlled oil/water separation. Water was selectively penetrated through the fabric and separated from oil after treating by CO 2 . A reversed wettability could be generated through simply treated with N 2 . It is expected that the as-prepared fabrics could be applied in smart oil/water separation due to the attractive properties of CO 2 -switchable system.
✓ 已验证
DOI
危险品化学品经营许可证（带存储）