Electrospun carbon nanofibers with multi-aperture/opening porous hierarchical structure for efficient CO2 adsorption

In this work, we report the preparation of polyacrylonitrile (PAN)-based activated carbon nanofibers composited with different concentrations of reduced graphene oxide (rGO/ACNF) (1%, 5%, and 10% relative to PAN weight) by a simple electrospinning method. The electrospun nanofibers (NFs) were carbonized and physically activated to obtain activated carbon nanofibers (ACNFs). Texture, surface and elemental properties of the pristine ACNFs and composites were characterized using various techniques. In comparison to pristine ACNF, the incorporation of rGO led to changes in surface and textural characteristics such as specific surface area (SBET), total pore volume (Vtotal), and micropore volume (Vmicro) of 373 m2/g, 0.22 cm3/g, and 0.15 cm3/g, respectively, which is much higher than the pristine ACNFs (e.g., SBET = 139 m2/g). The structural and morphological properties of the pristine ACNFs and their composites were studied by Raman spectroscopy and X-ray diffraction (XRD), and field emission scanning electron microscopy (FE-SEM) respectively. Carbon dioxide (CO2) adsorption on the pristine ACNFs and rGO/ACNF composites was evaluated at different pressures (5, 10, and 15 bars) based on static volumetric adsorption. At 15 bar, the composite with 10% of rGO (rGO/ACNF0.1) that had the highest SBET, Vtotal, and Vmicro, as confirmed with BET model, exhibited the highest CO2 uptake of 58 mmol/g. These results point out that both surface and texture have a strong influence on the performance of CO2 adsorption. Interestingly, at p < 10 bar, the adsorption process of CO2 was found to be quite well fitted by pseudo-second order model (i.e., the chemisorption), whilst at 15 bar, physisorption prevailed, which was explained by the pseudo-first order model.

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Carbon Dioxide Adsorption on Carbon Nanofibers with Different Porous Structures

Applied Sciences ◽

10.3390/app11167724 ◽

2021 ◽

Vol 11 (16) ◽

pp. 7724 ◽

Cited By ~ 1

Author(s):

Yu-Chun Chiang ◽

Chih-Cheng Huang ◽

Wei-Ting Chin

Keyword(s):

Carbon Nanofibers ◽

Co2 Capture ◽

Co2 Adsorption ◽

Breakthrough Curves ◽

Porous Structures ◽

Carbon Dioxide Adsorption ◽

Cyclic Tests ◽

Surface Areas ◽

Co2 Adsorption Capacity ◽

Hierarchical Pore

Electrospinning techniques have become an efficient way to produce continuous and porous carbon nanofibers. In view of CO2 capture as one of the important works for alleviating global warming, this study intended to synthesize polyacrylonitrile (PAN)-based activated carbon nanofibers (ACNFs) using electrospinning processes for CO2 capture. Different structures of PAN-based ACNFs were prepared, including solid, hollow, and porous nanofibers, where poly(methyl methacrylate) (PMMA) was selected as the sacrificing core or pore generator. The results showed that the PMMA could be removed successfully at a carbonization temperature of 900 °C, forming the hollow or porous ACNFs. The diameters of the ACNFs ranged from 500 to 900 nm, and the shell thickness of the hollow ACNFs was approximately 70–110 nm. The solid ACNFs and hollow ACNFs were microporous materials, while the porous ACNFs were characterized by hierarchical pore structures. The hollow ACNFs and porous ACNFs possessed higher specific surface areas than that of the solid ACNFs, while the solid ACNFs exhibited the highest microporosity (94%). The CO2 adsorption capacity on the ACNFs was highly dependent on the ratio of V<0.7 nm to Vt, the ratio of Vmi to Vt, and the N-containing functional groups. The CO2 adsorption breakthrough curves could be curve-fitted well with the Yoon and Nelson model. Furthermore, the 10 cyclic tests demonstrated that the ACNFs are promising adsorbents.

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High electrochemical performance carbon nanofibers with hierarchical structure derived from metal-organic framework with natural eggshell membranes

Journal of Colloid and Interface Science ◽

10.1016/j.jcis.2019.11.008 ◽

2020 ◽

Vol 560 ◽

pp. 811-816 ◽

Cited By ~ 1

Author(s):

Tian-Lu Cui ◽

Jun-Ying He ◽

Chun-Sen Liu

Keyword(s):

Electrochemical Performance ◽

Carbon Nanofibers ◽

Hierarchical Structure ◽

Metal Organic Framework ◽

Metal Organic ◽

Eggshell Membranes ◽

Organic Framework

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Cobalt oxide nanoparticles embedded in flexible carbon nanofibers: attractive material for supercapacitor electrodes and CO2 adsorption

RSC Advances ◽

10.1039/c6ra06077c ◽

2016 ◽

Vol 6 (57) ◽

pp. 52171-52179 ◽

Cited By ~ 20

Author(s):

Nousheen Iqbal ◽

Xianfeng Wang ◽

Jianlong Ge ◽

Jianyong Yu ◽

Hak-Yong Kim ◽

...

Keyword(s):

Cobalt Oxide ◽

Carbon Nanofibers ◽

Co2 Adsorption ◽

Oxide Nanoparticles ◽

Effective Strategy ◽

Cobalt Oxide Nanoparticles

In this study, a novel and effective strategy has been developed to produce a flexible hierarchical hybrid nanostructured membrane for multifunctional applications.

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TEPA impregnation of electrospun carbon nanofibers for enhanced low-level CO2 adsorption

Nano Convergence ◽

10.1186/s40580-020-0217-y ◽

2020 ◽

Vol 7 (1) ◽

Cited By ~ 2

Author(s):

Jie Wang ◽

Adedeji Adebukola Adelodun ◽

Jong Min Oh ◽

Young Min Jo

Keyword(s):

Carbon Nanofibers ◽

Co2 Adsorption ◽

Low Level

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The Application of Hollow Carbon Nanofibers Prepared by Electrospinning to Carbon Dioxide Capture

Polymers ◽

10.3390/polym13193275 ◽

2021 ◽

Vol 13 (19) ◽

pp. 3275

Author(s):

Yu-Chun Chiang ◽

Wei-Ting Chin ◽

Chih-Cheng Huang

Keyword(s):

Carbon Nanofibers ◽

Co2 Adsorption ◽

Physical Adsorption ◽

Exothermic Reaction ◽

Activation Process ◽

Co2 Activation ◽

Hollow Nanofibers ◽

Adsorption Performance ◽

Reduce Emissions ◽

Hollow Carbon

Coaxial electrospinning has been considered a straightforward and convenient method for producing hollow nanofibers. Therefore, the objective of this study was to develop hollow activated carbon nanofibers (HACNFs) for CO2 capture in order to reduce emissions of CO2 to the atmosphere and mitigate global warming. Results showed that the sacrificing core could be decomposed at carbonization temperatures above 900 °C, allowing the formation of hollow nanofibers. The average outer diameters of HACNFs ranged from 550 to 750 nm, with a shell thickness of 75 nm. During the carbonization stage, the denitrogenation reactions were significant, while in the CO2 activation process, the release of carbon oxides became prominent. Therefore, the CO2 activation could increase the percentages of N=C and quaternary N groups. The major nitrogen functionalities on most samples were O=C–NH and quaternary N. However, =C and quaternary N groups were found to be crucial in determining the CO2 adsorption performance. CO2 adsorption on HACNFs occurred due to physical adsorption and was an exothermic reaction. The optimal CO2 adsorption performance was observed for HACNFs carbonized at 900 °C, where 3.03 mmol/g (1 atm) and 0.99 mmol/g (0.15 atm) were measured at 25 °C. The degradation of CO2 uptakes after 10 adsorption−desorption cyclic runs could be maintained within 8.9%.

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Confined growth of 2D MoS2 nanosheets in N-doped pearl necklace-like structured carbon nanofibers with boosted lithium and sodium storage performance

Chemical Communications ◽

10.1039/c9cc07291h ◽

2020 ◽

Vol 56 (1) ◽

pp. 141-144 ◽

Cited By ~ 8

Author(s):

Huayu Wu ◽

Xiue Zhang ◽

Qianhui Wu ◽

Yue Han ◽

Xiaoyu Wu ◽

...

Keyword(s):

Carbon Nanofibers ◽

Hierarchical Structure ◽

Shell Structures ◽

Mos2 Nanosheets ◽

Storage Performance ◽

Confined Growth ◽

2D Nanosheets ◽

Sodium Storage

N-Doped amber necklace-like structured MoS2@carbon nanofibers (ANL MoS2@CNFs) were fabricated via the confined growth, constructing a hierarchical structure with 2D nanosheets, yolk–shell structures, 1D nanofibers, and 3D cross-linked networks.

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New Design for a Differentially Pumped Hydration Chamber for a Siemens IA

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010006427x ◽

1971 ◽

Vol 29 ◽

pp. 44-45

Author(s):

R. C. Moretz ◽

G. G. Hausner ◽

D. F. Parsons

Keyword(s):

Electron Microscopy ◽

Water Vapor ◽

Electron Diffraction ◽

Water Vapor Pressure ◽

Biological Materials ◽

Thin Membrane ◽

Reliable System ◽

System A ◽

Water Films ◽

Aperture Opening

Electron microscopy and diffraction of biological materials in the hydrated state requires the construction of a chamber in which the water vapor pressure can be maintained at saturation for a given specimen temperature, while minimally affecting the normal vacuum of the remainder of the microscope column. Initial studies with chambers closed by thin membrane windows showed that at the film thicknesses required for electron diffraction at 100 KV the window failure rate was too high to give a reliable system. A single stage, differentially pumped specimen hydration chamber was constructed, consisting of two apertures (70-100μ), which eliminated the necessity of thin membrane windows. This system was used to obtain electron diffraction and electron microscopy of water droplets and thin water films. However, a period of dehydration occurred during initial pumping of the microscope column. Although rehydration occurred within five minutes, biological materials were irreversibly damaged. Another limitation of this system was that the specimen grid was clamped between the apertures, thus limiting the yield of view to the aperture opening.

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Relationships between hierarchical structure and properties in macromolecular systems

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126950 ◽

1987 ◽

Vol 45 ◽

pp. 440-443

Author(s):

E. Baer

Keyword(s):

Uniaxial Tension ◽

Hierarchical Structure ◽

Inorganic Material ◽

Hierarchical Structures ◽

Bone Collagen ◽

Structure And Properties ◽

Connective Tissues ◽

Scale Level ◽

Fibrous Protein ◽

Macromolecular Systems

The most advanced macromolecular materials are found in plants and animals, and certainly the connective tissues in mammals are amongst the most advanced macromolecular composites known to mankind. The efficient use of collagen, a fibrous protein, in the design of both soft and hard connective tissues is worthy of comment. Very crudely, in bone collagen serves as a highly efficient binder for the inorganic hydroxyappatite which stiffens the structure. The interactions between the organic fiber of collagen and the inorganic material seem to occur at the nano (scale) level of organization. Epitatic crystallization of the inorganic phase on the fibers has been reported to give a highly anisotropic, stress responsive, structure. Soft connective tissues also have sophisticated oriented hierarchical structures. The collagen fibers are “glued” together by a highly hydrated gel-like proteoglycan matrix. One of the simplest structures of this type is tendon which functions primarily in uniaxial tension as a reinforced elastomeric cable between muscle and bone.

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