NEW JOURNAL OF CHEMISTRY
·
2017
·Vol. 41
·期 10
·4031-4039
·
IF 3.269
Xiaofei Song,Jianmin Hao,Yijia Bai,Limin Han,Guangfei Yan,Xu Lian,Jiansheng Liu
Al–Cu–Co alloys containing different intermetallic compound phases were fabricated by the arc-melting method and used as heterogeneous catalysts for solvent-free cyclohexane oxidation by oxygen. The element composition and bulk structure were characterized by ICP-OES, XRD, SEM, TEM and XPS. Co species were the major active component and a small amount of Cu dissolved in the Al13Co4 phase of the alloy exhibited a synergetic effect on improving the catalytic activity. Cu dissolved in the Al13Co4 phase, a decagonal quasicrystal approximant with a special atomic arrangement structure, could increase the electrical conductivity and accelerate electron transfer during the catalytic oxidation of cyclohexane, and thus improved the catalytic activity of the alloy. Among all the alloys prepared in the present work, the Al60Cu5Co35 alloy exhibited the best catalytic performance with a cyclohexane conversion of 6.4% and a total selectivity of 95.2% to cyclohexanol and cyclohexanone. No significant change in the catalytic activity of the Al60Cu5Co35 alloy was observed after five cycles.
研究领域:
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Jialong Zhu,Hong Fan,Jintao Wan
Transparent, hard, and flexible multifunctional coatings have a wide range of applications; however, most of them need organic solvents. Here, we present a solvent-free and UV-cured coating made from fluorinated epoxy MTQ silicone resin combined with branched triepoxy siloxane as the reactive diluent. After UV-initiated ring-opening polymerization in the presence of a triarylsulfonium hexafluoroantimonate catalyst, the resultant cured coating exhibits high transparency (∼92%, 550 nm), pencil hardness (7H), and flexibility (1 mm bending diameter) due to the formed organic–inorganic nanostructures in a highly cross-linked network. The triepoxy siloxane significantly reduces the viscosity before curing and increases cross-link density of the coating. The coating without any volatile content shows a smooth surface with low roughness (Rq = 0.46 nm) and delivers an anti-smudge ability owing to perfluorinated chains inherited from the MTQ resin. Furthermore, even after 3000 abrasion cycles, the coating still has a water contact angle greater than 90°, displaying excellent wear resistance. Our work provides a promising way to access high-performance multifunctional coatings in a more sustainable manner.
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 POWER SOURCES
·
2022
·
IF 9.794
Chen Lv,Wenjie He,Jiangmin Jiang,Enmeng Zhen,Hui Dou,Xiaogang Zhang
The manufacturing processes of electrodes have a prominent influence on the cost and performance of lithium-ion capacitors (LICs), which are limited by the conventional wet-coated method due to the usage of solvent. Herein, the solvent-free Li 4 Ti 5 O 12 (LTO) electrodes are prepared with electrostatic spraying deposition using for LICs. Owing to the solvent being avoided during the manufacturing, the dry-sprayed electrode exhibits a higher porosity (∼40%) than that of the wet-coated electrode (∼30%), together with a larger electrochemically active surface area. The optimized microstructure improves electrolyte infiltration and offers effective Li-ion transport paths, which reduces the electrochemical polarization and boosts the specific capacity of the dry-sprayed electrode. When the current density increases from 0.5 C to 10 C, the reversible capacity retention of the dry-sprayed electrode is 74%, which is higher than that of the wet-coated electrode (56%). In addition, the powder resistivity of the dry-sprayed electrode decreases sharply by introducing two-dimension (2D) graphene nanoplate (GN) as the conductive agent, thus side effects have been effectively suppressed during the spraying process. As a result, the assembled LICs using the dry-sprayed LTO electrodes show superior energy density and excellent cycling performance, demonstrating this novel fabrication method has practical application prospects.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
·
2023
·Vol. 41
·期 11
·1725-1732
·
IF 4.3
Wang Yuepeng,Yang Lei,Zhang Luzhi,Huang Hongfei,Qian Bo,Gu Shijia,You Zhengwei
Polyurethane is widely used for its versatility in design and range of performance. Self-healing and recyclable dynamic polyurethane networks have attracted extensive attention due to their potential to extend service life and ensure safety in use, as well as to promote sustainable use of resources. Developing green and environment-friendly methods to obtain this material is an interesting and challenging task, as the majority of current dynamic polyurethane networks utilize the solution polymerization method. The use of solvents makes the processes complicated, harmful to environment, and increase the cost. Poly(oxime-urethanes) (POUs) are emerging dynamic polyurethanes and show great potential in diverse fields, such as biomaterials, hot melt adhesives, and flexible electronics. In this study, we utilized the solubility properties of dimethylglyoxime in raw material poly(ethylene glycol) to prepare POUs through bulk polymerization for the first time. This method is simple, convenient and cost-efficient. Simultaneously, copper ion coordination improves POUs strength and dynamic properties, with mechanical strength up from 0.54 MPa to 1.03 MPa and self-healing recovery rate up from 85.5% to 91.8%, and activation energy down from 119.6 kJ/mol to 95.4 kJ/mol. To demonstrate the application of this technology, self-healing and stretchable circuits are constructed from this dynamic polyurethane network.
研究领域:
材料科学
·
绿色化学
✓ 已验证
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2020
·
IF 4.469
Zhongfeng Ji,Yong Liu,Fanglin Du
A mechanically robust, transparent, solvent-free, and self-cleaning coating (GPMS-DTDA/PFTS) was fabricated based on the co-hydrolysis/condensation of the Dibutyltin dilaurate, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (curing agent), while the different amount of 1H,1H,2H,2H-Perfluorodecyltrimethoxysilane were added to the system to reduce the surface energy of the coating. The morphology and properties of the polysiloxane-based coating were characterized by SEM, FTIR, UV–vis-NIR. The as-synthesized GPMS-DTDA/PFTS-based coating displays excellent performance with the hardness of 8H, superior adhesion (5B), high transmittance (95.2 %), hydrophobicity (CA: 107°) as well as outstanding properties of self-cleaning and weather resistance.
研究领域:
材料科学
·
表面化学
✓ 已验证
产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2019
·
IF 4.182
Yeqing Wang,Jian Zhang,Xiangju Meng,Shichao Han,Qiuyan Zhu,Na Sheng,Liang Wang,Feng-Shou Xiao
In this work, we show sustainable and efficient synthesis of nanosized EMT zeolite under organotemplate-free and solvent-free conditions, which not only completely avoids the use of organic templates for production of NOx and CO 2 but also effectively reduces the formation of polluted water. In addition, the yield of EMT zeolite is significantly enhanced by this route, compared with conventional hydrothermal synthesis . The nanosized EMT zeolite obtained has good crystallinity, uniform crystal size distribution, and high surface area. Ion-exchange tests show that the nanosized EMT zeolite owes high Ca 2+ and Mg 2+ ion exchange capacity at room temperature, which is potentially important for softening hard water in the industrial processes. Catalytic tests in Knoevenagel condensation show that the nanosized EMT zeolite exhibits higher activity than that of the EMT zeolite synthesized using organic template, indicating the importance of the nanosized EMT zeolite as a base catalyst.
研究领域:
材料科学
·
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2019
·
IF 6.97
Mingjie Chen,Rui-Min Li,Troy Runge,Jin Feng,Jing Feng,Songnan Hu,Qing-Shan Shi
Cellulose acetate is one of the oldest synthetic thermoplastic polymers and has various applications including usage as films, fibers, and membrane products. Traditionally, cellulose acetate is prepared by reacting cellulose with acetic anhydride in acetic acid using sulfuric acid as a catalyst. This process suffers from extensive depolymerization of the cellulose molecules and corrosion of the equipment from the use of the acidic solvent and catalyst. Herein we present an acid-free cellulose acetylation process using vinyl acetate as both the reactant and reaction medium and 1-ethyl-3-methylimidazolium acetate as the catalyst. The obtained cellulose acetate was confirmed by FTIR, NMR, and XRD studies. Additionally, the reaction kinetics, mechanism of the process, and properties of the obtained cellulose acetate were studied. Cellulose triacetate was obtained by our process within 2 h at 90 °C. The reaction kinetics was described with the classical pseudo-first-order rate expression of heterogeneous cellulose acetylation. The reaction mechanism was shown to be a peel-off mechanism similar to that of cellulose acetylation by the traditional acetic acid process. The molecular weight of the cellulose acetate produced by this new process was significantly higher than that from the traditional acetic acid process because of the absence of strong acids, which can depolymerize cellulose. In summary, we describe a new acid-free process to produce cellulose acetate that limits cellulose depolymerization and avoids the use of corrosive chemicals.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE CHINESE CHEMICAL SOCIETY
·
2015
·Vol. 62
·期 8
·722-727
·
IF 0.648
Hongyu Zhang,Bin Lu,Xuelin You,Fengyu Ma,Jingxiang Zhao,Qinghai Cai
The two-component mixed oxides FeVO x with various molar ratio of Fe to V were prepared and their phase composition, structure and morphology were determined by XRD and SEM. This prepared material was employed for liquid-phase oxidation of octanol using H 2 O 2 as oxidant. The mixed oxide FeVO x with 2.5 : 1 of Fe to V molar ratio was found to be an effective catalyst with high selectivity to octanal under solvent-free condition. The relationship between the catalytic performance and phase compositions of the mixed oxides was investigated by the test of its activity and XRD characterization. The catalytic action of the active sites including redox and acidic sites formed by interaction between VO x and FeO x on the surface of the catalyst was discussed. The catalyst was easily recovered and reused.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Crystals
·
2018
·Vol. 8
·期 2
·73
·
IF 2.144
Yucun Cui,Zheng Yan,Mengli Li,Jie Zhu,Longfeng Zhu,Hong Yao,Xuebo Cao
We report a solvent-free synthesis of all silica Beta zeolite using a cheap organic template of tetraethylammonium bromide (TEABr). The method includes mixing, grinding and heating solid raw material in the absence of water solvent but the presence of zeolite seeds. The absence of water solvent significantly improves the efficiency of synthesis, while the addition of seeds remarkably enhances the crystallization rate. In addition, the use of a cheap organic template of TEABr greatly decreases the synthesis cost. The effects of the reaction compositions, including the molar ratios of NH4F/SiO2, TEABr/SiO2, and mass ratios of seeds to the silica, on the synthesis of the pure product were investigated using different temperature. Physicochemical characterizations, including XRD, SEM, TG and N2sorption, show that the zeolitic product has good crystallinity, uniform crystals, and high surface area.Keywords:zeolite;all silica Beta;solvent-free synthesis;tetraethylammonium bromide;cheap
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
Reaction Kinetics Mechanisms and Catalysis
·
2022
·Vol. 135
·期 1
·219-231
·
IF 1.843
Li Jianyu,Zhang Jiaojing,Wang Yuanyuan,Wang Huan,Song Hua
The high efficiency amphiphilic CTAB-PW( x )/g-C 3 N 4 catalysts with different quaternary ammonium phosphotungstate (CTAB-PW) loadings ( x , wt%) were designed and successfully synthesized. The catalysts were characterized by XRD, SEM, FTIR, XPS and BET. The effects of CTAB-PW loading, oxidative desulfurization (ODS) conditions and different sulfides on the performance of ODS were investigated using green oxidant H 2 O 2 as oxidant in solvent-free reaction system. The results show the crystalline structure of CTAB-PW and g-C 3 N 4 were retained in CTAB-PW( x )/g-C 3 N 4 hybrid materials. And the use of cetyltrimethylammonium bromide (CTAB) can save cost and prevent the application of harmful solvents. The CTAB-PW( x )/g-C 3 N 4 with CTAB-PW loading of 50% exhibited the best ODS performance. The benzothiophene, dibenzothiophene removal rate of 99.9% and 4,6-dimethyl-dibenzothiophene removal rate of 98.9% were achieved under the conditions of catalyst dosage of 0.04 g, O/S molar ratio of 8, reaction temperature of 60 °C for 2 h. Moreover, the removal rate of benzothiophene still maintained at 94.3% after the catalyst was recovered for 5 times, which was mainly due to the presence of amino group in g-C 3 N 4 , which can inhibit the leaching of active phosphotungstate (HPW). Graphical abstract
研究领域:
催化化学
·
环境化学
✓ 已验证
产品关联
DOI
高影响因子
Advanced Materials Interfaces
·
2021
·Vol. 8
·期 21
·2101544
·
IF 6.147
Guozheng Xia,Mei Lin,Yi Jiayu,Hu Jinkang,Li Bowen,Youbing Mu,Xiaobo Wan
How to realize fast and strong underwater adhesion has gained much attention recently. Although some mussel-inspired adhesives that can be cured underwater have been reported, reports on underwater adhesion with both high bonding strength and rapid curing capability are still rare. Furthermore, organic solvents are generally utilized in these adhesives, which are eco-unfriendly. Here, by taking advantages of the strong underwater adhesion capability of catecholic groups in mussel adhesion proteins (MAPs) and the fast curing capability of polyurethane (PU) prepolymer, a facile yet powerful strategy towards a fast-curing mussel-inspired underwater adhesive is reported. The biomimetic adhesive, PUP-PPG-DBHP, is a liquid composed of isocyanate-terminated polypropylene glycol (PPG) and isocyanate-terminated dopamine bis(hydroxymethyl)propionate (DBHP), which can be directly applied underwater without solvent dilution and reach an average bonding strength around 1.2 MPa at a curing time of only around 30 s on glass substrates. Meanwhile, underwater curing process of PUP-PPG-DBHP shows good tolerance toward pH value, ionic strength, and temperature change. Such an engineering adhesive opens an innovative and facile route to a feasible solution for underwater engineering field.
研究领域:
材料科学
·
生物仿生学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2022
·Vol. 13
·期 1
·124
·
IF 5.719
Hui Kong,Xiaomin Luo,Peng Zhang,Jianyan Feng,Pengni Li,Wenjie Hu,Xuechuan Wang,Xinhua Liu
Self-healing anti-corrosion materials are widely regarded as a promising long-term corrosion protection strategy, and this is even more significant if the damage can be monitored in real-time and consequently repaired. Inspired by the hierarchical structure of human skin, self-healing, solvent-free polyurethane/carbon nanotubes composites (SFPUHE-HTF-CNTs) with a skin-like bilayer structure were constructed. The SFPUHE-HTF-CNTs were composed of two layers, namely, a hydrophobic solvent-free polyurethane (SFPUHE-HTF) containing disulfide bonds and fluorinated polysiloxane chain segments consisting of a self-healing layer and CNTs with good electrical conductivity consisting of a corrosion protection layer, which also allowed for the real-time monitoring of damage. The results of corrosion protection experiments indicated that the SFPUHE-HTF-CNTs had a low corrosion current density (8.94 × 10−9A·cm−2), a positive corrosion potential (−0.38 V), and a high impedance modulus (|Z| = 4.79 × 105Ω·cm2). The impedance modulus could still reach 4.54 × 104Ω·cm2after self-healing, showing excellent self-healing properties for anti-corrosion protection. Synchronously, the SFPUHE-HTF-CNTs exhibited a satisfactory damage sensing performance, enabling the real-time monitoring of fractures at different sizes. This work realized the effective combination of self-healing with corrosion protection and damage detection functions through a bionic design, and revealed the green, and low-cost preparation of advanced composites, which have the advantage of scale production.Keywords:solvent-free polyurethane;carbon nanotubes;anti-corrosion;self-healing;damage monitoring
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
危险品化学品经营许可证（带存储）