Polymers
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2018
·Vol. 10
·期 1
·75
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IF 2.935
Jianyan Feng,Xuechuan Wang,Peiying Guo,Yujie Wang,Xiaomin Luo
In order to improve the dispensability of graphene oxide (GO) in waterborne polyurethane (WPU), sulfonated graphene (SGO) with superior dispersity was prepared by modifying graphene oxide with sodium 2-chloroethane sulfonate to introduce hydrophilic sulfonic groups into the structure. SGO/WPU composites were prepared using isophorone diisocyanate (IPDI), polytetramethylene ether glycol (PTMEG 2000), dimethylolpropionic acid (DMPA) and SGO as raw materials. The influence of SGO content on composite properties were investigated. The structure and morphology of SGO and SGO/WPU composites were characterized by infrared spectroscopy, X-ray diffractometry and transmission electron microscopy etc. Their mechanical properties and wear resistance were analyzed as well. The experimental results showed that SGO was successfully grafted onto polyurethane macromolecule by an in situ method and, with the introduction of sulfonic groups, the interfacial compatibility of GO and PU was improved significantly so that SGO evenly dispersed into WPU. The SGO that was grafted onto WPU macromolecules exhibited layered morphology with nanometers in the WPU matrix. With increasing SGO content, the tensile strength and the wear resistance of the film increased, but the addition of more than 0.8 wt % SGO yielded unfavorable results. When the added amount of SGO was 0.8 wt % of WPU, the tensile strength of the composite film was 46.53% higher than that of the blank group, and the wear resistance of the film was remarkably improved, which was due to a strong interaction between the SGO and WPU phases. Thus, the conclusion can be drawn that appropriate amount of SGO addition can enhance the mechanical properties of SGO/WPU composite film.Keywords:sulfonated grapheme;waterborne polyurethane;in situ method;mechanical resistance properties;wear resistance
研究领域:
材料科学
·
化学工程
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2018
·
IF 3.779
Dashui Yuan,Jing Ding,Jie Zhou,Lei Wang,Hui Wan,Wei-Lin Dai,Guofeng Guan
A highly efficient ZIF-8/g-C 3 N 4 photocatalyst was prepared by a facile ultrasonic in-situ method. The structure-property relationship of ZIF-8/g-C 3 N 4 composite was analysed by various characterization techniques. The comprehensive study illustrated that ZIF-8 served as an adsorbent to capture the substrates in the contaminated solution and increased the contact possibilities of the active species and substrates. The formation of ZIF-8/g-C 3 N 4 hybrids helped to significantly enhance visible light absorption and facilitate charge transfer and separation of the photogenerated electron-hole pairs, eventually improving the photocatalytic efficiency. Meanwhile, compared with ZIF-8/g-C 3 N 4 composites obtained by incipient wetness impregnation method, ultrasonic in-situ synthesis contributed to hindering the aggregation of g-C 3 N 4 nanosheets and simultaneously promoting ZIF-8 well dispersed on the surface of g-C 3 N 4 nanosheets. The synergistic effect of preparation method and special hybrid structure was studied in-depth and could significantly enhanced photocatalytic activity and stability for the degradation of organic pollutants (such as tetracycline, rhodamine B and methyl orange) under visible light irradiation. The reaction rate constant K values of optimal ratio sample for degradation of TC, RhB and MO were 0.039 min −1 , 0.034 min −1 and 0.012 min −1 , respectively 1.69, 3.96 and 4.10 times as big as that of pure g-C 3 N 4 . Meanwhile, the photoresponse current of optimal ratio sample was 3.3 μA/cm 2 , around 4.73 times as big as that of the pure g-C 3 N 4 . A reasonable photocatalytic mechanism was proposed by the photoelectrochemical experiments and the controlled experiments using radical scavengers.
研究领域:
材料科学
·
环境科学
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Bowen Li,Zhiwen Zhang,Yijing Tang,Liyang Qin,Chengyuan Li,Pengze Li,Ye Song
Titanium dioxide (TiO 2 ) has always attracted much attention in the fields of semiconductors and photocatalysis due to its narrow band gap. Especially because of its excellent photocatalytic performance, its application research in water pollution treatment is extremely extensive. However, most studies have focused on modifying and transforming TiO 2 particles that are difficult to recycle and prone to secondary pollution to achieve better photocatalytic performance. In this paper, regular TiO 2 nanotubes were obtained by conducting secondary anodization on the titanium-based surface through the anodic oxidation method, and the Ag 3 PO 4 /TiO 2 structure was prepared by in-situ method. The results show that the photoelectric response of the TiO 2 oxide film loaded with Ag 3 PO 4 is significantly stronger than that of pure TiO 2 oxide film. Mild annealing (300℃) in an argon atmosphere after loading Ag 3 PO 4 can increase the photocurrent response intensity of the sample by 88 %. Based on the analysis of the results of SEM, TEM and XPS, Ag/Ag 3 PO 4 nanoparticles appeared on the surface of the nanotubes after annealing in an argon atmosphere. Furthermore, the results show that the carrier concentration of annealing at 400 °C is significantly higher than that of annealing at 300 °C, but the photocurrent response intensity is the opposite. This work will provide new inspirations for the modification and improvement of TiO 2 nanotube structures and the enhancement of their photoelectric properties.
研究领域:
半导体材料
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光催化
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纳米技术
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环境修复
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材料科学
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产品关联
DOI
高影响因子
Surfaces and Interfaces
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2024
·
IF 5.7
Yufeng Gan,Yuxiang Yang,Shunyan Ning,Yimin Liu,Yuezhou Wei,Xinpeng Wang,Deqian Zeng
Developing heterojunction photocatalysts is a critical method to augment the photocatalytic activity of single semiconductors. However, the instability of their heterostructure poses a significant challenge. Herein, a unique 0D/2D Mn 3 O 4 /CdS p-n photocatalyst has been prepared by a simple one-pot in-situ hydrothermal approach for H 2 production and methylene blue (MB) degradation. The optimized MC-0.18 (18 at% Mn) nanocomposite showed remarkable photocatalytic properties, producing a significantly higher H 2 generation rate of 1291 μmol· g −1 · h −1 , which was 13.7 and 9.2 times higher than that of pristine CdS and ex-situ synthesized MC-0.18-ex photocatalysts, respectively. MC-0.18 displayed the highest reaction rate at 0.0435 min −1 for MB degradation, which was approximately 2.6 and 6.3 times higher than CdS and Mn 3 O 4 , respectively. Active species capture experiments and ESR identified •OH and •O 2 − as the main substances involved in MB degradation. Importantly, MC-0.18 demonstrated excellent stability and reusability in photocatalytic H 2 production and MB degradation cycle tests. The formation of unique p-n heterostructures results in enhanced photoactivity due to the matched band alignment between ultrafine Mn 3 O 4 nanoparticles and CdS nanosheets , leading to a high charge separation capacity. This study offers a facile route to design p-n heterojunctions that have remarkable charge transfer abilities to promote H 2 production and degrade organic dyes.
研究领域:
材料科学
·
环境科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
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