Nature Communications
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2024
·Vol. 15
·期 1
·1-12
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IF 14.7
Liu Yang,Shang Huishan,Zhang Bing,Yan Dongpeng,Xiang Xu
The C–C bond cleavage of biomass-derived glycerol to generate value-added C1 products remains challenging owing to its slow kinetics. We propose a surface fluorination strategy to construct dynamic dual hydrogen bonds on a semiconducting BiVO 4 photoelectrode to overcome the kinetic limit of the oxidation of glycerol to produce formic acid (FA) in acidic media. Intensive spectroscopic characterizations confirm that double hydrogen bonds are formed by the interaction of the F–Bi–F sites of modified BiVO 4 with water molecules, and the unique structure promotes the generation of hydroxyl radicals under light irradiation, which accelerates the kinetics of C–C bond cleavage. Theoretical investigations and infrared adsorption spectroscopy reveal that the double hydrogen bond enhances the C=O adsorption of the key intermediate product 1,3-dihydroxyacetone on the Bi–O sites to initiate the FA pathway. We fabricated a self-powered tandem device with an FA selectivity of 79% at the anode and a solar-to-H 2 conversion efficiency of 5.8% at the cathode, and these results are superior to most reported results in acidic electrolytes.
研究领域:
材料科学
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光电化学
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催化反应
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2024
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IF 8.4
Qichao Ding,Kedi Dong,Xinyu Si,Tonghu Xiao,Xing Yang
Amphiphobic membranes have attracted much attention in membrane distillation (MD) applications, due to its potential in simultaneously resisting membrane wetting and fouling when treating complex wastewater. The current amphiphobic membranes often require non-trivial design of multilevel re-entrant structure. Here we proposed a new class of amphiphobic membranes without multilevel re-entrant surface, by creating a composite poly(vinylidene fluoride)/polyvinyl alcohol/SiO 2 membrane with asymmetric structure and well-controlled small surface pores via the NTIPS method, followed by direct fluorination via chemically binding the –OH of polyvinyl alcohol and low surface energy moieties 1H,1H,2H,2H-perfluorodecyl-triethoxysilane, assisted by 3-aminopropyltriethoxysilane and trimesoyl chloride. The amphiphobic membrane showed superior liquid entry pressure above 5 bar with various simulated saline feeds containing surfactants and organic pollutants. The amphiphobic membrane demonstrated robust anti-wetting and anti-fouling performance through a series of 24-h direct contact MD experiments using the above feeds, presenting stable water flux and high rejection, e.g., flux of 50.6 kg/(m 2 ·h) and rejection >99.9 % with feed containing 3.5 wt% NaCl, 1 mM FA, and 2 mM SDS. The results demonstrated the fabrication of robust amphiphobic membrane through simple procedure utilizing the synergy between pore structure and surface chemistry, inspiring more efforts to design adequate membranes for treating complex wastewater.
研究领域:
材料科学
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环境工程
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化学工程
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产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2020
·Vol. 9
·期 5
·1593-1603
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IF 7.059
Guoming Gao,Ximeng Wang,Qifeng Chen,Caibo Xie,Jie Zheng,Huailin Fan,Lulu Ma,Ruifang Guan,Yanfen Fang,Xun Hu
Surface fluorinated TiO2 has received extensive attention in recent years due to the improved photocatalytic reactivity compared with that of pure TiO2. However, the synergy of surface fluorine (FS) and oxygen vacancy (VO) is not clear and needs further study. Here we systematically studied the effect of FS, VO and acidic sites of TiO2 nanosheets on the selective photocatalytic oxidation of benzylamine to imine. The photocatalytic activity first increased and then decreased as the content of FS decreased and VO increased. The photocatalytic activity reached a summit with the imine yield of 92.1% over TiO2-B-6 h, which is mainly due to the synergy between FS and adjacent VO, forming the frustrated Lewis pair that boosts the activation of O2. The varied contents of FS and VO not only cause an evident change in the amount of acidic sites, but also affect the band structure and separation efficiency of charge carriers. The experimental and calculation results demonstrate that the coexistence of FS and VO boosted the separation efficiency, density and mobility of photogenerated charge carriers, resulting in the improved photocatalytic activity. The improved photocatalytic activity can be attributed to the combined effects of FS, VO and acidic sites. This work provides a strategy for the explicit regulation of surface species on TiO2 nanosheets for improved photocatalytic activity.
研究领域:
材料科学
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环境科学
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化学工程
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DOI
高影响因子
CELLULOSE
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2015
·Vol. 22
·期 4
·2341-2348
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IF 3.573
Rao Xianmeng,Kuga Shigenori,Wu Min,Huang Yong
Ball mill-assisted surface-fluorination of cellulose nanofiber was studied for two solvents with different polarity as dispersion/reaction medium. Milling cellulose in neat toluene gave irregular-shaped decrystallized cellulose particles; addition of pentafluorobenzoyl chloride (PFBC) to the system gave partially fluorinated cellulose as thin flakes with smooth surfaces, which maintained original crystallinity. Milling in neat dimethyl formamide (DMF) caused partial dispersion of nanofibers without decrystallization; milling in PFBC/DMF gave more enhanced dispersion of surface-fluorinated nanofibers. Both fluorinated materials were hydrophobic, with water contact angles of 103°–113°. Bulk degree of esterification was 0.20 for toluene and 0.57 for DMF systems. These results show characteristic influences of solvent species in reactive ball milling of cellulose in terms of fibrillation and surface esterification of nanofibers.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
Materials Advances
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2022
·Vol. 3
·期 18
·7037-7042
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IF 0
Xiaoli Zhang,Yajun Lou,Lei Hu,Weijia Duan,Guojie Chen,Bingfeng Fan,Weiren Zhao,Xinhai Zhang
InP-based quantum dots (QDs) have attracted considerable interest in the optoelectronic field owing to their favorable properties. However, to date, the nonlinear optical properties and ultrafast photonics applications of InP-based QDs have rarely been explored. In this study, InP/ZnSe/ZnS QDs with surface fluorination treatment (InP-HF) have been fabricated. Consequently, the nonlinear saturable absorption properties of such InP-HF QDs with surface modification are explored by realizing a modulation depth of 3.27% and a saturable intensity of 1.10 MW cm−2. We report on the passive Q-switching of a diode-pumped Nd:YVO4 near-infrared laser at 1064 nm (∼1.0 μm) using InP-HF QDs as a SA. At this wavelength, the threshold of pump power is as low as 1 W, and the maximum average output power and the shortest pulse widths are 2.5 W and 178 ns, respectively. The laser results suggest that surface fluorination treated InP-HF QDs could be very promising for generating ultrashort pulse visible lasers.
研究领域:
光学
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材料科学
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光电子学
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DOI
DESALINATION
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2017
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IF 5.527
Jingcheng Cai,Xiaohua Liu,Yiming Zhao,Fei Guo
Polyacrylonitrile (PAN) solution was electrospun into fibrous membranes with nonwoven structure and quasi-parallel fibrous structure using a rotating drum collector. Surface fluorination treatment technique was applied to transform the intrinsically hydrophilic PAN membranes into hydrophobic membranes. A set of surface fluorination treated electrospun PAN membranes were tested for membrane desalination (MD) using a lab-scale air gap membrane desalination system . The results show that it is promising to use intrinsically non-hydrophobic membranes in MD after surface fluorination modification based on permeate flux and salt rejection ratio. In the MD application , we found that the fiber orientation combing with the flow direction of the feed could affect the mass transfer performance. The quasi-parallel fiber alignment , surface fluorination treatment, liquid entry pressure , permeate flux, and mass transfer coefficient were studied in detail in this work.
研究领域:
材料科学
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环境工程
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产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
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2019
·
IF 5.155
Guorong Hu,Jilin Wu,Ke Du,Zhongdong Peng,Ming Jia,Hao Yang,Yanbing Cao
The surface-fluorinated Li 4 Ti 5 O 12 nanowires/reduced graphene oxide composite is synthesized through a hydrothermal procedure. Lithium ion transport is promoted by forming a special morphology of lithium titanate nanowires, meanwhile, electronic transmission is facilitated by surface fluorination and conductive network of graphene coating. These three kinds of synergistic effects greatly improve the rate performance of lithium titanate . The surface-fluorinated Li 4 Ti 5 O 12 nanowires/reduced graphene oxide composite exhibits high specific capacities (167.5 mAh g −1 at 1 C and even 132.6 mAh g −1 at 10 C) and good cyclic stability (95% capacity remain after 300 cycles at 5 C). The influences of surface fluorination and graphene coating on electrochemical performance of lithium titanate are investigated in detail in terms of reversible capacity, cyclability and rate capability. Its excellent electrochemical properties make it become possible to be a potential anode material for high-rate lithium-ion batteries applied in high power facilities.
研究领域:
材料科学
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电化学
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纳米科技
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能源存储
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锂离子电池
✓ 已验证
DOI
高影响因子
COMBUSTION SCIENCE AND TECHNOLOGY
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2023
·
IF 1.9
Hongxia Zhang,Fei Xiao
Incorporating fluorine-containing organic compounds onto the surface of aluminum powder in order to reduce the mass transfer distance and increase the heat transfer efficiency during the combustion of aluminum powder and fluoride is a difficult problem to solve due to the fact that aluminum powder contains almost no chemical functional groups. Herein, monodisperse Al@PVDF microspheres were prepared by a simple dry-spray method by directly combining Al powder and PVDF. The contents of PVDF and Al in Al@PVDF microspheres can be adjusted arbitrarily. PVDF can be tightly and uniformly bound on the surface of aluminum particles by characterization of Al@PVDF microspheres. Al@PVDF microspheres can improve the hydrophobic properties of aluminum powder and effectively inhibit the corrosion of water and strong alkaline solutions on aluminum. Al@PVDF microspheres exhibit greater hydrophobicity than aluminum powder and are capable of efficiently inhibiting the corrosion of aluminum by water and strong alkaline solutions. Additionally, the ignition and reaction performance of Al@PVDF microspheres under high temperature conditions are also studied in detail. Al@PVDF microspheres exhibit lower ignition temperature and higher reactivity than pure aluminum powder. Al@PVDF microspheres can also effectively suppress the combustion agglomeration of aluminum powders.
研究领域:
材料科学
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化学工程
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燃烧科学
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产品关联
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 111
·91140-91146
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IF 3.84
Shuang-Shuang Zhang,Shao-Kui Cao,Su Wang,Qiao-Ling Zhao,Jian-Zhuang Chen,Kun Cui,Zhi Ma
Well-defined α-fluorinated alkyl ester, ω-carboxyl telechelic polystyrenes (PS) were synthesized via combining aminolysis of RAFT-polystyrene and thiol–ene “click” reaction simultaneously. The perfluoroalkyl end groups were –CF3, –(CF2)2–CF3 and –(CF2)7–CF3, respectively. Highly ordered porous films of such telechelic PS with an average pore size about 1.00 μm were fabricated via a static breath-figure process. With the content of fluorine on the surface of porous films increasing from 1.04 wt%, to 1.64 wt% and 2.97 wt%, respectively, the water contact angle (WCA) of such porous films increased from 112° to 116° and 121° ± 0.4°, respectively, indicating their hydrophobicity. Interestingly, microspheres with average diameters of ca. 0.30–0.65 μm can be fabricated via a static BF process using methanol instead of water as the vapor atmosphere in the glass vessel.
研究领域:
高分子化学
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材料科学
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纳米技术
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表面工程
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软物质物理
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DOI
高影响因子
危险品化学品经营许可证（带存储）