JOURNAL OF ORGANIC CHEMISTRY
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2022
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IF 4.198
Jun Xu,Chao Peng,Bolin Yao,Hua-Jian Xu,Qiang Xie
This report describes a method for the deoxyfluorination of alcohols with KF as the fluorine source via in situ generation of highly active CF3SO2F. Diverse functionalities, including halogen, nitro, ketone, ester, alkene, and alkyne, are well tolerated. Mild conditions, a short reaction time, and a wide substrate scope make this method an excellent choice for the construction of C–F bonds.
研究领域:
有机化学
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合成化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials Research Express
·
2019
·Vol. 6
·期 4
·045601
·
IF 1.449
Hao Li,Genliang Hou,Qi Tian,Song Bi,Zhaohui Liu,Yangyang Lin,Jin Tang,Xunjia Su
Fluorinated graphene oxide (FGO) with high fluorine content is a suitable alternative for superhydrophobic materials due to the existence of the C–F bond. In this paper, we demonstrate a facile, large-scale method for the preparation of FGO with higher oxygen content and fluorine content by adopting proper oxidants and solvent to oxidize commercial graphite fluoride (GIF) on the basis of modified Hummers' method. Chemical composition, morphology and hydrophobicity are characterized by FT-IR, XPS, TGA, TEM and contact angle (CA) test respectively. The results indicate that the increase in oxygen content is accompanied by a decrease in fluorine content and FGO fabricated by using KMnO4 and the mixture of CH3COOH: H2SO4 with a volume ratio of 3:1 owns higher O/C and F/C ratio and superhydrophobicity. The oxidation mechanism is speculated that fluorine atom detaches from GiF in a strong oxidation environment, resulting in the restoration of sp2 C=C bond partly, and then sp2 C=C bond could be oxidized by KMnO4 or K2FeO4 efficiently. More oxygen groups broaden the applications of FGO as hydrophobic materials.
研究领域:
材料科学
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化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2025
·
IF 11.3
Shan Yao,Jieying Lin,Shaoxiong He,Yang Bai,Mingge Jin,Feng Zhu,Jingyun Fang,Mengye Wang
Perfluoroalkyl substances (PFAS) are environmentally persistent, bioaccumulative and toxic pollutants. However, thorough degradation of PFAS remains exceptionally difficult due to the high dissociation energy of the C-F bond. Here, we report a viable strategy to markedly degrade PFAS completely by capitalizing on a harmless polytetrafluoroetylene (PTFE) as a piezocatalyst. Remarkably, perfluorooctanoic acid (PFOA), as one of the widely used PFAS, was almost completely removed with a degradation rate of 93.4 % and a defluorination rate of 91.5 % by the ultrasound excitation of PTFE for 1 h. On the basis of the intermediate analysis, we proposed an oxidation mechanism for the piezocatalytic PFOA degradation. Furthermore, this strategy was also efficient for the degradation of perfluoroheptanoic acid (PFNA), perfluorooctane sulfonate (PFOS) and hexafluoropropylene oxide dimer acid (Gen-X), implying its effectiveness to remediate water containing multiple PFAS. Impressively, due to the diverse energy gap between HOMO and LUMO energy of various PFAS, the degradation reaction kinetics of different PFAS are of significant difference. This study provides the deep insight into the piezocatalytic technique for the remediation of persistent and disparate PFAS.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2025
·
IF 11.3
Pengtao Cai,Tong Chen,Mingxiu Zhan,Xiaojun Ma,Masaki Takaoka,Chen Sun,Xiaodong Li
Per- and polyfluoroalkyl substances (PFAS) are known for their strong C-F bonds, which make them highly persistent in the environment and resistant to degradation. Among PFAS, perfluorobutane sulfonate (PFBS), a short-chain PFSA widely used as a replacement for long-chain PFAS like perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), has garnered attention due to its environmental persistence and toxicity. Although PFBS has lower bioaccumulation potential than its long-chain counterparts, it remains a significant pollutant with limited data available on its degradation mechanisms. To address this, the present study investigates PFBS degradation under subcritical water hydrothermal conditions. Various alkaline substances and additives were tested, and degradation products were analyzed by liquid and gas chromatography-mass spectrometry. Results show that 2 M NaOH at 325°C achieved an ∼99.4 % PFBS removal rate, and the degradation pathway began with the breakdown of the S-C bond, followed by C-F bond cleavage, resulting in the formation of smaller fluorinated compounds, including trifluoroacetic acid. Density functional theory (DFT) calculations provided detailed insights into the degradation mechanism, identifying hydroxide ion attack on the sulfonic acid group as the initial step and elucidating three distinct pathways for subsequent reactions. This study provides key insights into PFBS degradation mechanisms, emphasizing the synergistic effect of alkaline bases and additives. The findings support the optimization of subcritical hydrothermal treatment for PFAS removal, providing a scalable and environmentally sustainable solution.
研究领域:
环境科学
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化学工程
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理论计算
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2024
·
IF 12.2
Lijie Duan,Mengbin Gu,Minghao Wang,Liquan Liu,Xue Cheng,Xueqi Fan,Jun Huang
Widespread detection in soils and sediments underscores the potential threats posed by persistent, bioaccumulative and toxic perfluorooctane sulfonate (PFOS) to ecosystems and organisms. Nevertheless, the formidable energy of the C-F bond imparts stability and hampers degradation. This study investigates the potential of boron carbide (B 4 C), a hard-ceramic material often utilized in armor and abrasion contexts, for degrading solid-phase PFOS through ball milling. Following a 60-minute reaction period, PFOS degradation reached 100 %, while desulfurization stabilized at 13.9 %. Defluorination initially rose to 23.7 % but subsequently displayed a gradual decline. Fluoride ions, once released, were secured and the stable reservoir surface of B 4 C during the ball-milling process, leading to the formation of B-C-B-F chemical bonds, which was confirmed through characterization by XPS, FTIR, and solid-state NMR analyses. Furthermore, intermediate byproducts formed during the degradation of PFOS, encompassing perfluoroalkyl sulfonic acids (PFSAs) and perfluoro carboxylic acids (PFCAs), were identified. Eventually, the generation of free electrons, contributing to the facilitation of degradation for both PFOS and its intermediates, was confirmed through the DPPH experiment. This identification underscores the intricacy of the PFOS degradation pathway, which encompasses the generation and subsequent breakdown of these intermediates. These discoveries hold significance for pioneering sustainable and inventive methods to combat PFOS pollution across diverse applications. Furthermore, they enrich the comprehension of how mechanical forces can be leveraged for the eco-friendly removal of PFOS contaminants.
研究领域:
环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2020
·Vol. 55
·期 26
·12103-12113
·
IF 3.553
Jin Tianxiang,Chen Jianfa,Wang Chunyan,Qian Yong,Lu Limin
A three-dimensional (3D) fluorine-doped graphene aerogel (FGA) with rich semi-ionic C–F bonds was synthesized via a facile hydrothermal method and applied as the electrode material in supercapacitor. A porous 3D network structure with a high specific surface area of the FGA has been confirmed by the combination of scanning electron microscopy, transmission electron microscopy and N 2 adsorption method. X-ray photoelectron spectroscopy spectra indicated that the FGA was doped predominantly with semi-ionic C–F bonds, which ensured the high electronic conductivity and sufficient electrochemistry active sites of FGA. As a result, the FGA electrode showed a high specific capacity of 279.8 F g −1 at a current density of 0.5 A g −1 , which is much better than that of undoped graphene aerogel (UGA, 141.6 F g −1 ). Even though the current density increased to 10 A g −1 , 90.6% of its specific capacitance was retained. The FGA also maintained about 94.3% of the initial capacitance after 5000 cycles at a current density of 0.5 A g −1 . Furthermore, the assembled FGA//FGA symmetric supercapacitor presented a high energy density of 26.2 W h kg −1 at a power density of 899 W kg −1 . Accordingly, this work offers a facile and efficient approach to produce fluorine-doped graphene materials for high-performance supercapacitor applications.
研究领域:
材料科学
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能源存储
✓ 已验证
产品关联
DOI
高影响因子
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
·
2023
·Vol. 120
·期 52
·e2312480120
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IF 11.1
Yingkang Chen,Wenqiang Qu,Tao Luo,Hang Zhang,Junwei Fu,Hongmei Li,Changxu Liu,Dengsong Zhang,Min Liu
Tetrafluoromethane (CF4), the simplest perfluorocarbons, is a permanently potent greenhouse gas due to its powerful infrared radiation adsorption capacity. The highly symmetric and robust C–F bond structure makes its activation a great challenge. Herein, we presented an innovated approach that efficiently activates C–F bond utilizing protonated sulfate (–HSO4) modified Al2O3@ZrO2 (S-Al2O3@ZrO2) catalyst, resulting in highly efficient CF4 decomposition. By combining in situ infrared spectroscopy tests and density function theory simulations, we demonstrate that the introduced –HSO4 proton donor has a stronger interaction on the C–F bond than the hydroxyl (–OH) proton donor, which can effectively stretch the C–F bond for its activation. Consequently, the obtained S-Al2O3@ZrO2 catalyst achieved a stable 100% CF4 decomposition at a record low temperature of 580 °C with a turnover frequency value of ~8.3 times higher than the Al2O3@ZrO2 catalyst without –HSO4 modification, outperforming the previously reported results. This work paves a new way for achieving efficient C–F bond activation to decompose CF4 at a low temperature.
研究领域:
环境科学
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催化化学
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材料科学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2023
·
IF 13.6
Li Li,Ruoning Guo,Jie Gao,Jie Liu,Zhiwei Zhao,Xin Sheng,JunYu Fan,Fuyi Cui
Perfluorooctanoic acid (PFOA) is a representative persistent organic pollutant and its disposal by mechanochemical (MC) technology emerges in recent years. However, degradation mechanism of PFOA especially rupture of C−F bonds during MC process is still unclear. Therefore, we innovatively employed barium titanate as co-milling reagent in MC system to disclose an electron-dominated reduction process. By stimulating piezoelectric effect of BaTiO 3 under MC impact, free electrons were generated. The results implied more than 95.00% degradation and 60.00% defluorination efficiency were obtained after 6 h′ ball milling. DPPH• was used as probe to confirm the existence of piezo-excited electrons, which were further verified to be major reactive species by atmosphere experiments. Thus, PFOA destruction was dominated by reduction process, characterizing by breakage of C−F bonds induced by electrons. Accordingly, the fate of organic fluorides was explored and BaF 2 was identified as final product. The cleavage of carboxyl group initiated PFOA decomposition, following by successive removal of CF 2 groups and elimination of F − . Moreover, the practical experiments and reusable trials implied promising application of this method. Overall, this paper provides a novel perspective for reductive decomposition of PFOA by MC technology and reveals the major role of electrons during reaction process.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
·
2023
·
IF 3.6
Qijie Zou,Wei Zhang,Haoyue Wang,Guangwei Yin,Yongzhi He,Fangyi Li
The CF3 group attached to N-aryl hydrazone could be activated upon treatment with a suitable base, thus serving as an excellent C1 unit for the assembly of a series of 1,3,4-oxadiazoles by reaction with hydrazides. The transformation is proposed to proceed via the intermediate formation of a gem-difluorinated azoalkene. Furthermore, this reaction features simple conditions and a broad substrate scope with respect to both trifluoromethyl N-aryl hydrazones and hydrazides.
研究领域:
有机化学
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合成化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
·
2021
·
IF 3.975
Yingdong Duan,Qizheng Li,Biyun Peng,Shaobo Tan,Zhicheng Zhang
In the present work, diverse vinyl monomers were successfully grafted onto poly(vinylidene fluoride-hexafluoropropylene) P(VDF-HFP) via direct activation of C F bonds using Cu(0)/4,4′-dimethyl-2,2′-bipyridyl (DMDP) as catalyst under mild conditions. The structure of the graft copolymer was carefully characterized, and the initiating site was confirmed at the same time. Moreover, the kinetic results indicated the controlled behavior of the graft polymerization, and the composition of the graft copolymer can be regulated by changing the reaction conditions. This work may provide a facile strategy to endow P(VDF-HFP) copolymer with new functions via directly activating C F bonds.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）