JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2023
·
IF 9.9
Qiao Cu,Chaoqun Shang,Guofu Zhou,Xin Wang
The fabrication of freestanding electrodes for Na + storage is necessary to achieve high energy density. However, the large radius of Na + results in a large volume fluctuation and sluggish reaction kinetics of active materials, particularly at a high active material content, thereby impeding electrochemical performance with undesirable cycling performance or rate capability. In this study, a freestanding electrode based on the “NiSe grafted on Cu 2-x Se” heterostructure with double-carbon protective shells (NiSe/Cu 2-x Se@C@NCNFs) was successfully constructed for Na + storage. In this microstructure, N -doped carbon nanofibers (NCNFs) serve as the stem of the twinborn NiSe/Cu 2-x Se heterostructure with a built-in electric field, where NiSe improves Na + absorption and Cu 2-x Se enhances Na + diffusion. The “graft” design enabled the freestanding NiSe/Cu 2-x Se@C@NCNFs electrode with a high active mass content of 76.1 wt% to exhibit superior electrochemical performance for Na + storage (75 mAh g −1 at 2 A g −1 ) compared to those of Cu 2-x Se@C@NCNFs (26 mAh g −1 at 2 A g −1 ) and NiSe@C@NCNFs (9 mAh g −1 at 2 A g −1 ).
研究领域:
材料科学
·
电化学
·
能量存储
✓ 已验证
DOI
高影响因子
JOURNAL OF PHYSICS D-APPLIED PHYSICS
·
2022
·Vol. 55
·期 20
·204002
·
IF 3.409
Huajun Xu,Gang Chen,Fei Du,Xin Wang,Yohan Dall’Agnese,Yu Gao
In spite of outstanding theoretical specific capacity (∼3590 mAh g−1), huge volume change during lithiation/delithiation and poor conductivity hinder the practical applications of pure Si anodes for lithium ion batteries (LIBs), requiring conductive additives and porous architectures. In this work, flexible and freestanding composite films made of two-dimensional Ti3C2Tx MXene nanosheets and silicon particles embedded in carbon nanofiber (denoted as Ti3C2Tx-Si@CNF) were prepared via electrospinning and used as LIB anodes. This new electrode design provides a 3D network architecture and high conductivity favorable for good electrochemical performance and long cycle life. Ti3C2Tx-Si@CNF electrodes, containing 28% silicon retained high specific capacity of ∼1580 mAh g−1 after 100 cycles at 0.1 A g−1 and 720 mAh g−1 after 1000 cycles at 1 A g−1, and delivered a great rate performance with 289 mAh g−1 at a current density of 5 A g−1. This is a significantly enhanced performance compared with Si particles embedded in CNF without Ti3C2Tx (denoted Si@CNF). This work proposes a scalable manufacturing strategy for developing high-performance silicon-based anodes, overcoming the low conductivity and volume expansion issues.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
高影响因子
Catalysis Science & Technology
·
2017
·Vol. 7
·期 24
·6000-6012
·
IF 5.773
Wenfeng Han,Chunpeng Zhang,Haili Wang,Shenglan Zhou,Haodong Tang,Luteng Yang,Zhikun Wang
Hydrofluorocarbons (HFCs) which are usually potent greenhouse gases are regulated by the Montreal Protocol and its amendments, especially the recent Kigali Amendment. Dehydrofluorination of HFCs is an efficient route for the conversion of these greenhouse gases to value added and environmentally benign chemicals. Although AlF3 with strong Lewis acidity catalyzes dehydrofluorination, it also favors carbon deposition. MgF2 with weak acidity inhibits coking significantly. Unfortunately, MgF2 sinters dramatically at temperatures below 300 °C leading to the low activity for dehydrofluorination. In the present work, we report that sub-nano MgF2 embedded in carbon fibers and electrospun MgF2 fibers prevent sintering of MgF2 during dehydrofluorination reaction. Via simple and one-step electrospinning and calcination in a N2 (for embedded MgF2) or air (for MgF2 fibers) atmosphere, embedded MgF2 with particle sizes between 3–6 nm and pure MgF2 fibers with diameters of around 100 nm were fabricated. No sintering was observed following reaction at 450 °C. The fine MgF2 particles and MgF2 fibers facilitate the formation of under coordinated Mg species in MgF2 which are the weak acid sites. By embedding MgF2 or fabrication of MgF2 fibers, weak acid sites are increased significantly, while strong acid sites remain almost unchanged. Hence, they show significantly higher reaction rates than MgF2 prepared by precipitation of Mg(CH3COO)2·4H2O with NH4F for the dehydrofluorination of 1,1,1-trifluoroethane (HFC-143a) to VDF (CH2CF2) at 450 °C.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2022
·Vol. 14
·期 17
·3584
·
IF 4.967
Mingpan Zhang,Fuli Wang,Xinran Shi,Jing Wei,Weixia Yan,Yihang Dong,Huiqiang Hu,Kai Wei
In this study, an iron oxide/carbon nanofibers (Fe2O3/CNFs) composite was prepared by a combination of electrospinning and hydrothermal methods. The characterization of Fe2O3/CNFs was achieved via scanning electron microscopy (SEM), infrared spectroscopy (IR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). It is shown that when the hydrothermal reaction time was 180 °C and the reaction time was 1 h, the Fe2O3nanoparticle size was about 90 nm with uniform distribution. The photodegradation performance applied to decolorize methyl orange (MO) was investigated by forming a heterogeneous Fenton catalytic system with hydrogen peroxide. The reaction conditions for the degradation of MO were optimized with the decolorization rate up to more than 99% within 1 h, which can decompose the dyes in water effectively. The degradation process of MO by Fenton oxidation was analyzed by a UV-visible NIR spectrophotometer, and the reaction mechanism was speculated as well.Keywords:Fe2O3;carbon nanofibers;heterogeneous Fenton;methyl orange (MO)
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials Horizons
·
2025
·
IF 10.7
Yiliang Liu,Ying Lin,Zhixin Cai,Yongzhen Ma,Hongwei Zhou,Wei Chai,Qibin Yuan,Haibo Yang
With the rapid development of modern electronic technology, electromagnetic wave (EMW) absorption materials play a crucial role in solving the problem of electromagnetic radiation pollution. By designing unique microstructures or composite magnetic components, the EMW attenuation ability of carbon nanofibers (CNFs) can be enhanced. However, the ultra-high conductivity of CNFs leads to impedance mismatch, necessitating the introduction of components that can rapidly optimize dielectric properties for improved impedance matching. In this study, Co0.7Fe0.3@CNFs@MnO2 (CFCM) was fabricated by coating MnO2 nanosheets on necklace-like CoFe@carbon nanofiber composites. The coated MnO2 nanosheets not only enhance the EMW attenuation ability, but also improve impedance matching. The results indicate that the minimum reflection loss of the sample is −62.7 dB, and the effective absorption bandwidth reaches 6.5 GHz. This work presents a valuable method to prepare outstanding EMW absorption materials with a necklace-like 3D network hierarchical structure.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING RESEARCH & DESIGN
·
2024
·
IF 3.7
Yunfei Zhao,Hang Sheng,Jiashun Xi,Tingting Jiang,Dong Wang,Jian Zhang,Zheng Li,Bing Wang,Xiaohui Xu,Haifeng Zhang,Bo Yuan,Runlong Hao,Yi Zhao,Tianhao Wang
In the reaction system with NaBH 4 as a hydrogen donor, inhibiting the formation of hydrogen is the key to promote the efficient catalytic hydrogenation of CO 2 . In this study, nanoscale zero-valent nickel supported on carbon nanofibers (Ni 0 /CNFs) was fabricated as a catalyst for CO 2 hydrogenation in aqueous NaBH 4 solution. The characteristics of Ni 0 /CNFs were examined. By SEM, it was observed that spherical nickel nanoparticles were distributed homogeneously on the surface of strip-shaped carbon nanofibers. EDS mappings indicated that elements were evenly distributed on the catalyst, which might contribute to the uniform exposure of active sites. Via XRD, it was determined that all the diffraction peaks corresponded to the crystal face of nickel metal and that the absence of diffraction peaks of carbon nanofibers indicated that the crystallinity of the carrier was low. XPS study showed that nickel existed on the catalyst surface in two forms: zero valence metal and oxidation state. The effects of catalyst addition amount, NaBH 4 concentration, NaOH dosage, stirring rate on the yield of formate and hydrogen generation rate (HGR) were investigated. By optimizing the above parameters, the concentration of formate reached 150 mmol/L and the hydrogen production rate was 10.55 mL/min. Compared with the non-catalytic conditions, the concentration of formate increased by 57 % and the HGR decreased by 78 %. Moreover, the relationship between CO 2 hydrogenation and NaBH 4 hydrolysis was clarified. This research could enhance comprehension of CO 2 hydrogenation in aqueous NaBH 4 solution and contribute to the development of CO 2 capture and utilization storage technology. The significance of this study lies in clarifying the connection between CO 2 hydrogenation and borohydride hydrolysis in CO 2 catalytic hydrogenation technology.
研究领域:
化学工程
·
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Nanomaterials
·
2021
·Vol. 11
·期 9
·2203
·
IF 5.076
Hong Wang,Yuejin Ma,Wenming Zhang
Nanoscale Fe3O4-Sn@CNFs was prepared by loading Fe3O4and Sn nanoparticles onto CNFs synthesized via electrostatic spinning and subsequent thermal treatment by solvothermal reaction, and were used as anode materials for lithium-ion batteries. The prepared anode delivers an excellent reversible specific capacity of 1120 mAh·g−1at a current density of 100 mA·g−1at the 50th cycle. The recovery rate of the specific capacity (99%) proves the better cycle stability. Fe3O4nanoparticles are uniformly dispersed on the surface of nanofibers with high density, effectively increasing the electrochemical reaction sites, and improving the electrochemical performance of the active material. The rate and cycling performance of the fabricated electrodes were significantly improved because of Sn and Fe3O4loading on CNFs with high electrical conductivity and elasticity.Keywords:Fe3O4;Sn;carbon nanofibers;lithium-ion batteries;anode material
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COMPOSITES SCIENCE AND TECHNOLOGY
·
2023
·
IF 9.1
Xiangjie Gong,Tao Yang,Yan Song,Xiaodong Tian,Zihui Ma,Zhanjun Liu
MOFs-reinforced electrospun carbon nanofibers offer a wide range of applications in the field of energy storage. In this study, ZIF-67 nanoparticles were produced and combined with polyacrylonitrile for electrospinning before being stabilized and carbonized to form a carbon nanofiber. BET, FT-IR, EA, DSC , and other techniques were used to investigate the stabilizing behaviors of PAN electrospun fiber with varying ZIF-67 concentrations at different temperatures. Under the same stabilizing settings, it was discovered that PAN electrospun fiber containing ZIF-67 nanoparticles could absorb more oxygen, promoting a higher degree of cyclization and crosslinking. Therefore, it was preferred to prepare carbon nanofibers at a lower stabilization temperature. Importantly, the degree of stability and disorder of the PAN/ZIF-67 stabilized fiber has been described by the FT-IR and the Raman spectra . This research deepens understanding about the formation of MOF-reinforced carbon nanofibers and expands our knowledge of the stability of PAN/MOF hybrid fibers.
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Ling Chen,Anning Sun,Jianwei Zhang,Derong Meng,Peichen Han,Feiyun Chen,Fengqiang Nan,Ping Du,Weidong He
High-energy propellant always encounters deficient mechanical properties and unstable combustion behavior under low temperature, leading to difficulties in subsequent use. Herein, the reinforcement filler carbon nanofibers (CNFs) were pioneered introduced into nitroguanidine propulsion, meanwhile, the molecular model and structure–function relationship of high-solid content propellant system was constructed. A sequence of characterizations manifested that CNFs were integrated well in propulsion system. The result of mechanical properties demonstrated that anti-impact strength increased with the increase content of CNFs in propellant, and a proper content range from 0.25 % to 1.0 % exerted better mechanical strength than that of high content under different temperature conditions. A “wire-tie” structure acting bridging effect that exhibit buffer exoenergic effect in terms of the enhancement mechanism was proposal as well, combing the theoretical calculated interaction of nitroguanidine (NQ) and nitrocellulose/nitroglycerin (NC/NG). Additionally, the analysis of thermal decomposition kinetic of propellant by conventional iso -conversional rate methods demonstrated that the addition of CNFs can could furtherly reduce the activation energy of NQ-GP, which is accord with the result of linear fitting methods. It also demonstrated that the thermal decomposition behavior of propellant was influenced by different high-pressure conditions and CNFs content, including T p and heat-release. Additionally, propellant integrated with CNFs burning steadily under different temperatures, and the burning rate coefficient and burning pressure exponent of propellant could be also flexible tuned with proper content of CNFs. Hence, the presented study highly broadens the application scope of reinforcement nanofiller, and will be potential of value to the community development in high-energy and high strength gun propulsion in aspect of combining experimental and theoretical calculation.
研究领域:
材料科学
·
推进剂工程
·
分子动力学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Weisheng Dai,Yao Wang,Weijuan Guo,Guofu Wang,Muqing Qiu
The effects of Fe(II) and humic acid on U(VI) immobilization onto oxidized carbon nanofibers (Ox-CNFs, pyrolysis of bacterial cellulose) were investigated by batch, spectroscopic and modeling techniques, with results suggesting that, Ox-CNFs exhibited fast adsorption rate (adsorption equilibrium within 3 h), high adsorption performance (maximum adsorption capacity of 208.4 mg/g), good recyclability (no notable change after five regenerations) in the presence of Fe(II) towards U(VI) from aqueous solutions (e.g., 40 % reduction and 10 % adsorption at pH 8.0), which was attributed to the various oxygen-containing functional groups, excellent chemical stability, large specific surface area and high redox effect. U(VI) adsorption increased with increasing pH from 2.0 to 5.0, then high-level plateau and remarkable decrease were observed at 5.0–6.0 and at pH > 6.0, respectively. According to FT-IR and XPS analysis, a negative correlation between U(VI) reduction and organic in the presence of Fe(II) implied that U(VI) reduction was driven by Fe(II) while inhibited by humic acid. The interaction mechanism of U(VI) on Ox-CNFs was demonstrated to be adsorption and ion exchange at low pH and reduction at high pH according to XPS and surface complexation modeling. These findings filled the knowledge gaps pertaining to the effect of Fe(II) on the transformation and fate of U(VI) in the actual environment. This carbon material with distinctive performance and unique topology offers a potential platform for actual application in environmental remediation.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2016
·Vol. 4
·期 33
·12799-12806
·
IF 8.262
Xintong Zhang,Wei Wang,Wenxin Shi,Jiaojie He,Hui Feng,Yongpeng Xu,Fuyi Cui,Ce Wang
Microbial growth in water poses a growing threat to humans. Nutrient starvation is an effective and green manner to control microbial growth in water. The general coexisting phosphate and organic carbon in water can both serve as nutrients for microbial metabolism, and thus one can take a heavy toll on the performance of a nutrient-starvation antibacterial approach based on the other. Herein, carbon nanofibers with embedded LaCO3OH nanoparticles (LCNFs) were rationally synthesized by carbonizing electrospun polyacrylonitrile nanofibers containing La-species. The LCNFs served as a capture agent for both phosphate and organic matter to realize more effective nutrient-starvation antibacterial activity for water security. The LCNFs rendered high phosphate removal efficiency through the strong chemical bond between LaCO3OH and phosphate, even for trace phosphate concentrations. At the same time, organic nutrients could be synchronously cut down by LCNFs, which resulted in more stringent nutrient-deficient conditions to control microbial growth in water effectively.
研究领域:
环境科学
·
材料科学
·
生物学
✓ 已验证
DOI
高影响因子
Materials Today Nano
·
2025
·
IF 8.2
Pingan Chen,Sizeng Hong,Xiangcheng Li,Yingli Zhu,Fu Chen,Mengke Qiao
Carbon nanofibers can be widely used in the field of electromagnetic wave absorption due to corrosion resistance, low density and good chemical stability. Here, we report a strategy to achieve strong microwave absorption capability by adjusting the crystallinity of carbon nanofibers containing Al 2 O 3 and TiO 2 . TiO 2 with Ti 3 C 2 T x MXene as a precursor decreases the crystallization temperature of Al 2 O 3 from 1400 °C to 800 °C in the carbon nanofibers. The diameter distribution of carbon nanofibers is uniform, though the surface of carbon nanofibers is getting rough with Ti 3 C 2 T x content increasing. The minimum reflection loss of carbon nanofibers is -55.78 dB at a thickness of 4.32 mm; the effective absorption bandwidth reaches 5.41 GHz (12.59-18 GHz) at a thickness of 1.67 mm, almost covering the Ku band. The excellent microwave absorption performance can be attributed to the synergistic effect of the non-crystalline carbon matrix and crystalline Al 2 O 3 /TiO 2 , in which the former improves impedance matching with free space, while the latter enhances the attenuation capability to the electromagnetic wave.
研究领域:
材料科学
·
电磁学
✓ 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）