Journal of Materials Chemistry A
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2019
·Vol. 7
·期 38
·21953-21958
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IF 10.733
Yanze Liu,Yiming Zuo,Shuai Li,Jiani Li,Li Li,Caixia Liu,Shumalia Ashraf,Pengfei Li,Bo Wang
Porous organic frameworks (POFs) are an important class of materials, which have attracted great interests in recent years. The post modification of porous organic frameworks provides an efficient way to fine tune the properties of POFs for specific applications. However, most of the post functionalization methods need harsh reaction conditions and specific reagents and lead to a notable pore width decrease, which hinder the pore accessibility. Herein, we designed and synthesized a thiophene based POF with high surface area and stability. A straightforward post-oxidation of thiophene based POFs by meta-chloroperbenzoic acid introduced sulfone groups as hydrogen bonding sites in the channel with a less effected pore width in a controllable manner. The hydrogen bond acceptor sulfone groups could promote the adsorption of ammonia and enhance the proton conductivity of phosphoric acid or imidazole infiltrated POFs. The proton conductivity of phosphoric acid doped oxidized thiophene based POFs is over 10−3 S cm−1 at 120 °C under anhydrous conditions, which could be a promising candidate for fuel cells.
研究领域:
材料科学
·
化学工程
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DOI
高影响因子
Nature Communications
·
2025
·Vol. 16
·期 1
·1-11
·
IF 15.7
He Chun-Ting,Yu Li-Hong,Liu Haiming,Wang Qing,Ye Zi-Ming,Zhang Jia,Wang Li-Dong,He Mei-Qian,Zhang Xue-Feng,Du Hong-Gang,Lu Zi-Wei,Yang Jian,Huang Hai-Hua,Chen Xiao-Ming
Covalently bonded metal-free electrocatalysts exhibit significant potential for sustainable energy technologies, yet their performances remain unsatisfactory compared with metal-based catalysts. Herein, we propose an all-organic electrocatalyst, MEC-2, that conforms to the infrequent oxide path mechanism in alkaline oxygen evolution reaction through post-oxidation modification. MEC-2 achieves an intrinsic overpotential of 257.7 ± 0.6 mV at 10 mA·cm −2 and possesses durability with negligible degradation over 100,000 CV cycles or 250 h of operation at 1.0 A·cm −2 , being comparable to the advanced metal-based OER electrocatalysts. The 18 O-labeled operando characterization and theoretical calculations unveil that post-oxidation modification enhances the electron affinity to OH intermediates, and adjusts the adsorption configuration and proximity distance of O intermediates, thereby promoting direct O−O radical coupling. In this work, we show a fresh perspective for understanding the role of non-metallic elements/functional groups in electrocatalysis, and to a certain extent, narrows the gap between all-organic electrocatalysts and metal-based electrocatalysts.
研究领域:
能源材料科学
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电化学
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理论计算
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产品关联
DOI
PubMed
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2019
·Vol. 29
·期 32
·1900134
·
IF 15.621
Xiao He,Haksong Sin,Bin Liang,Zahid Ali Ghazi,Abdul Muqsit Khattak,Niaz Ali Khan,Hamideh Rezvani Alanagh,Lianshan Li,Xiaoquan Lu,Zhiyong Tang
To realize selective separation of important small molecules in organic solvents with high permeability is highly desired but not attained yet, because it requires stringent control over selectivity in nanofiltration membranes. Here, a thiophene-containing conjugated microporous polymer membrane, in which the pore size is finely tuned at the angstrom scale through postoxidation of the thiophene moieties, is reported. The successful modification is confirmed by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and water contact angle, leading to obvious pore size reduction evidenced by nitrogen adsorption. Upon postmodification, the selectivity of the membrane can be effectively controlled. In the pristine membrane, the methanol permeance reaches 32 liters per square meter per hour per bar (L m −2 h −1 bar −1 ) with a molecular weight cut-off (MWCO) of 800 g mol −1 . Significantly, after in situ postmodification of thiophene moieties, the largest pore size is reduced from 1.73 to 1.48 nm, giving rise to a remarkable decrease of MWCO from 800 to 500 g mol −1 , while the permeance of methanol still maintains as high as 21 L m −2 h −1 bar −1 .
研究领域:
材料科学
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化学工程
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纳米技术
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Yafei Zhang,Xiaojing Tian,Kai Zhang,Kaixuan Zhao,Yang Wang,Chenwei Ma,Jingjing Guo,Wenhang Wang
Although iron in meat is an important trace element for human diet, its presence also induces postprandial oxidative stress and aggravates the condition of patients with iron overload. To overcome this situation, a type of new tunable Fe-absorption bioactive materials was constructed in this study. First, four phenolic acids (Caffeic acid, Gallic acid, Protocatechuic acid, Chlorogenic acid) were grafted onto chitosan. Then, the copolymers were prepared into micron-level microspheres by emulsification method, which were characterized in adsorption isotherms (Langmuir model), swelling behavior and digestion characteristics. In order to verify the practical application effect of microspheres, Protocatechuic acid grafted chitosan microspheres as the representative were used in sirloin powder to observe their effects in vitro digestion and rat experiment. In the present study, microspheres were innovatively applied in meat consumption, which significantly inhibited the oxidation of meat in the process of digestion and effectively controlled the iron absorption. These results are expected to play an important role in promoting the healthy consumption of meat around the world, improving gastrointestinal redox status through dietary assistance, and treating diseases related to iron overload.
研究领域:
食品科学
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生物技术
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营养学
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材料科学
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生物化学
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产品关联
DOI
PubMed
高影响因子
ACS Applied Polymer Materials
·
2024
·
IF 4.4
Qincheng Ma,Honglin Zhou,Xiang Shao,Junbao Chen,Yujie Cheng,Mengxin Chen,Yizhang Jiang,Xiangxiang Chen,Qingping Ke,Ying Wang,Jun Tang,Yunyuan Dong,Ping Cui
Liquid–liquid biphasic reactions are widely used in academic research and industrial production; however, they have always suffered from low reactivity. In this work, a variety of linear polymeric catalysts were prepared by reversible addition–fragmentation chain transfer polymerization and postoxidation steps. The amphiphilicity of polymeric catalysts was imparted by varying the addition ratios of hydrophilic 1,1,3,3-tetramethyl-2-(4-vinylbenzyl) guanidine, hydrophobic styrene, and catalyst precursor 2,2,6,6-tetramethyl-4-piperidyl methacrylate, thus forming stable Pickering emulsions. Such Pickering emulsion systems with an abundant interfacial area and a unique interfacial environment can promote the selective oxidation reaction. As exemplified by 2,2,6,6-tetramethylpiperidinooxy-mediated oxidation of cinnamyl alcohol, the selectivity of cinnamaldehyde in Pickering emulsions was 97.2% with a turnover frequency of 5.0 mol·mol–1·min–1, which is higher than reported results. The carbon dioxide responsiveness of the guanidine group on the polymers allowed for fast demulsification after the reaction, and the recycled polymer maintained high activity after 10 runs. This polymer-stabilized Pickering emulsion provides a valuable pathway for efficient green catalytic oxidation reactions.
研究领域:
化学工程
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材料科学
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催化
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绿色化学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）