JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2022
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IF 9.965
Guozhen Qin,Jianfeng Zheng,Yifan Li,Yatao Yang,Xingmin Liu,Xiaojin Han,Zhanggen Huang
Mainly exposed crystal facets and controllable morphology play a key role in the final performance of the preparation of specific nanomaterials . In the present study, a metal–organic framework pyrolysis method without adding solvent modifiers was developed. By adding CO in the calcination atmosphere to change atmosphere ratio, Fe 3 O 4 nanostructures are exposed with different crystal planes and evaluated their performance in NH 3 -SCR reaction. This study proves that SCR catalytic activity of Fe 3 O 4 nanocrystals is dependent on morphology and crystal facet. Compared with materials exposed (1 0 0), catalysts with more (1 1 1) show stronger deNO x performance. The preferential exposure of Fe 3 O 4 (1 1 1) crystal facets increases the concentration of adsorbed oxygen on the catalyst, showing higher surface acidity , and enhances the interaction among NO, O 2 and catalyst, which is conducive to SCR reaction. This is supported by DFT calculations . The results present a great application prospect in preparing nanomaterials with specific crystal structures to effectively treat pollutants.
研究领域:
材料科学
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环境科学
✓ 已验证
DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
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2023
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IF 3.4
Zhiyun Zhang,Zhiqiang Yu
In this paper, the mechanical properties and thermal expansibility of cyanate resin (CE) copolymerization modified by epoxy resin (EP) under medium-low temperature curing process were studied. The curing temperature of the modified resin was analyzed, and the results showed that the initial curing temperature of the copolymerization resin was reduced by 87°C compared with the blend resin and further reduced when dibutyltin-dilaurate was used. The results of mechanical properties test showed that the tensile and bending strength of the modified resin were the highest, which were 55.5 and 97.3 MPa, respectively. The results of scanning electron microscopy showed that the modified resin with 80 wt% cyanate content had the coarsest tensile and bending sections, the largest number of fracture stripes and rich layers, so it had relatively better toughness. The linear thermal expansion coefficient (CTE) of modified resin was determined and the results showed that when the loading of cyanate was 80 wt%, the CTE of the modified resin reached the lowest, only 6.36 × 10 −5 °C −1 .
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
APPLIED SURFACE SCIENCE
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2021
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IF 6.707
Qinwei Zhang,Ruinian Xu,Ning Liu,Chengna Dai,Gangqiang Yu,Ning Wang,Biaohua Chen
In this work, a Ni-supported CeO 2 -Al 2 O 3 catalyst, called NiCeAl-RMO (reduced metal-oxide), was prepared via air calcination and H 2 reduction of NiCeAl-LDH (layered double hydroxide). The NiCeAl-RMO catalyst shows superior CO 2 methanation activity, especially at low temperature (250 °C), and it performed 78.6% CO 2 conversion with ∼ 100% CH 4 selectivity. Compared with NiAl-RMO, the NiCeAl-RMO catalyst prepared via the Ce-doping strategy has significantly improved CO 2 methanation activity. Characterizations revealed that Ce doping would increase the amount of active Ni 0 species, cause a large number of oxygen vacancies, and generate new moderate basicity sites on the catalyst. In addition, in situ DRIFTS found that, unlike the RWGS + CO methanation mechanism over NiAl-RMO, the CO 2 methanation mechanism over NiCeAl-RMO followed the formate pathway by generating bidentate carbonate species, which was revealed as a key intermediate for enhancing the low-temperature activity of CO 2 methanation.
研究领域:
催化化学
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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
ACS Applied Materials & Interfaces
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2024
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IF 8.3
Haocong Wang,Wanfeng Zhu,Lanlan Xu,Jian Gong,Wenjia Li,Xiaojuan Liu
The high performance of intermediate-to-low temperature solid oxide fuel cells (ILT-SOFCs) closely depends on the catalytic activity of the cathode material. However, most high-activity perovskite cathodes are rich in Sr and will arise from Sr segregation during the long-term working, resulting in the decay of activity and stability. Herein, by regulating the calcined way and temperature, a type of self-assembled nanocomposite perovskite cathode is developed, the stoichiometric SrCo0.7Fe0.2Sc0.1O3−δ (SCFSc) powder self-separates into a cubic phase (Pm3̅m, Sc-rich) and a tetragonal phase (P4/mmm, Sc-fewer). Meanwhile, a single cubic phase is prepared with the same formula via calcining the SCFSc pellet. It is found that the nanocomposite cathode shows better oxygen reduction reaction catalytic activity than single cubic SCFSc, caused by lower impedance of oxygen surface exchange and bulk diffusion. Particularly, the nanocomposite SCFSc cathode with the self-assembled heterointerfaces mitigates the Sr segregation and shows a peak power density of 1.17 W cm–2 at 700 °C and excellent stability for ∼101 h at 600 °C. This work provides a strategy for the development of nanocomposite cathodes to mitigate cation segregation and improve catalytic activity and stability.
研究领域:
材料科学
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能源科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2023
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IF 15.1
Qinghong Ji,Xinxin Sheng,Xiaolong Li,Shuang Liu,Qiufei Chen,Pengzong Guo,Yabi Yang,Youyou Huang,Guoliang Zhang,Xiang Lu,Jinping Qu
Infrared stealth materials are in increasing demand with the development of infrared detection technology. However, most reported materials focus solely on emissivity control or temperature control, resulting in brief and less ideal infrared stealth effect. Herein, a double layer MXene@polyvinyl alcohol (PVA)/phase change capsules (PCC) aerogel composite inspired by the skin-fat structure of camel for infrared camouflage was successfully fabricated via a facile freeze-drying followed by spraying method. The PVA/PCC aerogel composite with high latent heat (155.2 J/g) and strong mechanical properties (772.6 kPa), obtained by an in-situ one-step method, is adopted as a temperature control layer, benefiting from the prominent thermal insulation of porous structure and effective heat absorption of PCC. The low emissivity (0.249) of the MXene layer on the surface of aerogel composite makes its radiation temperature recognized by the thermal imager much lower than its actual temperature. By integrating thermal insulation, heat absorption and emissivity reduction strategies, MXene@PVA/PCC aerogel shows no difference with the background in the infrared thermal imager (radiation temperature difference less than 10 °C), achieving superior infrared stealth for medium and low temperature scenarios, and provides novel ideas for developing more high-performance infrared stealth materials.
研究领域:
材料科学
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纳米技术
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热工程
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红外技术
✓ 已验证
产品关联
DOI
高影响因子
TEXTILE RESEARCH JOURNAL
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2023
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IF 2.3
Mingyuan Liu,Zikai Wu,Yuchen Meng,Zongwen Wang,Xinyang He,Jiatai Gu,Yue Zhang,Liming Wang,Xiaohong Qin
In order to solve the difficulty of starch being insoluble under medium and low temperature, a cationic starch slurry modified with etherification was developed. Raw starch was hydrolyzed by sodium hydroxide to improve the dispersion performance, and then the hydrolyzed starch was endowed with cationic groups by N-2,3-epoxy-propyl trimethyl ammonium chloride to improve the dispersion stability. Through various characterization methods, it was found that the quaternary ammonium cationic starch obtained was dissolved in water at medium and low temperature, and the starch structure was changed under the influence of sodium hydroxide and N-2,3-epoxy-propyl trimethyl ammonium chloride. Furthermore, the mechanical properties and abrasion resistance of cotton yarn treated with cationic starch could be significantly improved. Compared with the original yarn, the breaking strength of the yarn treated with cationic starch was increased by 70.05%, the hairiness index of the yarn was reduced by 87.5%, the abrasion resistance was increased by 500.00%, and the stiffness decreased by 276.47%. In addition, the Zeta potential of modified starch was positive, and the degree of etherification substitution of starch ranged from 0.02 to 0.26. The preparation method of etherified starch obtained has the advantages of environmental protection, low cost, and a simple process, which provides a novel way to construct textile size.
研究领域:
纺织科学
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化学工程
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材料科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）