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Synthesis and characterization of multiwalled CNT-PAN based composite carbon nanofibers via electrospinning.

Kaur N, Kumar V, Dhakate SR - Springerplus (2016)

Bottom Line: Also with stabilization, carbonization and graphitization diameter of nanofiber decreases.XRD results show that degree of graphitization increases on increasing CNT concentration because of additional stresses exerting on the nanofiber surface in the immediate vicinity of CNTs.TGA results shows wt loss decreases as CNT concentration increases in fibers.

View Article: PubMed Central - PubMed

Affiliation: Department of Physics, Krishna Institute of Engineering and Technology, Ghaziabad, India.

ABSTRACT
Electrospun fibrous membranes find place in diverse applications like sensors, filters, fuel cell membranes, scaffolds for tissue engineering, organic electronics etc. The objectives of present work are to electrospun polyacrylonitrile (PAN) nanofibers and PAN-CNT nanocomposite nanofibers and convert into carbon nanofiber and carbon-CNT composite nanofiber. The work was divided into two parts, development of nanofibers and composite nanofiber. The PAN nanofibers were produced from 9 wt% PAN solution by electrospinning technique. In another case PAN-CNT composite nanofibers were developed from different concentrations of MWCNTs (1-3 wt%) in 9 wt% PAN solution by electrospinning. Both types of nanofibers were undergone through oxidation, stabilization, carbonization and graphitization. At each stage of processing of carbon and carbon-CNT composite nanofibers were characterized by SEM, AFM, TGA and XRD. It was observed that diameter of nanofiber varies with processing parameters such as applied voltage tip to collector distance, flow rate of solution and polymer concentrations etc. while in case of PAN-CNT composite nanofiber diameter decreases with increasing concentration of CNT in PAN solution. Also with stabilization, carbonization and graphitization diameter of nanofiber decreases. SEM images shows that the minimum fiber diameter in case of 3 wt% of CNT solution because as viscosity increases it reduces the phase separation of PAN and solvent and as a consequence increases in the fiber diameter. AFM images shows that surface of film is irregular which give idea about mat type orientation of fibers. XRD results show that degree of graphitization increases on increasing CNT concentration because of additional stresses exerting on the nanofiber surface in the immediate vicinity of CNTs. TGA results shows wt loss decreases as CNT concentration increases in fibers.

No MeSH data available.


Related in: MedlinePlus

XRD spectra of carbon nanofiber
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Fig8: XRD spectra of carbon nanofiber

Mentions: Figures 7 and 8 shows XRD patterns of PAN nanofibers and carbon nanofibers. PAN fiber shows strong diffraction peak centered around 2θ angle of 16.67° and 29.462°, these two peaks represents the X-ray reflection of the (110) of a hexagonal structure and (112) crystallographic planes in PAN. However, in case of the PAN–CNT 1 wt% nanofibers, curve “B”, the peak centered on 2θ angle of 16.67° and 29.462°, these two peaks represents the X-ray reflection of the (110) of a hexagonal structure and (112), and 2θ angle of 44.37° represents the X-ray reflection of the (004) this is due to presence of CNT. In case of the PAN–CNT 2–3 wt% nanofibers, curve “C”, the peak centered on 2θ angle of 16.67° and 29.462°, these two peaks represents the X-ray reflection of the (110) of a hexagonal structure and (112), and 2θ angle of 44.37° represents the X-ray reflection of the (004) this is due to presence of CNT. But intensity of peaks is very high as comparison to 1 wt% of CNT (Hagewood 2004). In carbonized nanofibers intense diffraction peak as compared to stabilize fibres around 2θ angle of 24°–26° is attributed to (002) crystallographic plane of graphite crystallite. Degree of graphitization is determined from XRD results (Kim and Reneker 1999) by using formula (g = ((0.3440-d200)/(0.3440–0.3354)) × 100 and d200 = nλ/2sinθ where λ is wavelength, θ is diffraction angle and 0.3440 is interlayer spacing of fully non graphitized carbon (nm). Degree of graphitization for PAN nanofibers is −20 % and for PAN–CNT nanofibers is −41.86. Degree of graphitization increases due to presence of CNT in fibers.Fig. 7


Synthesis and characterization of multiwalled CNT-PAN based composite carbon nanofibers via electrospinning.

Kaur N, Kumar V, Dhakate SR - Springerplus (2016)

XRD spectra of carbon nanofiber
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4837748&req=5

Fig8: XRD spectra of carbon nanofiber
Mentions: Figures 7 and 8 shows XRD patterns of PAN nanofibers and carbon nanofibers. PAN fiber shows strong diffraction peak centered around 2θ angle of 16.67° and 29.462°, these two peaks represents the X-ray reflection of the (110) of a hexagonal structure and (112) crystallographic planes in PAN. However, in case of the PAN–CNT 1 wt% nanofibers, curve “B”, the peak centered on 2θ angle of 16.67° and 29.462°, these two peaks represents the X-ray reflection of the (110) of a hexagonal structure and (112), and 2θ angle of 44.37° represents the X-ray reflection of the (004) this is due to presence of CNT. In case of the PAN–CNT 2–3 wt% nanofibers, curve “C”, the peak centered on 2θ angle of 16.67° and 29.462°, these two peaks represents the X-ray reflection of the (110) of a hexagonal structure and (112), and 2θ angle of 44.37° represents the X-ray reflection of the (004) this is due to presence of CNT. But intensity of peaks is very high as comparison to 1 wt% of CNT (Hagewood 2004). In carbonized nanofibers intense diffraction peak as compared to stabilize fibres around 2θ angle of 24°–26° is attributed to (002) crystallographic plane of graphite crystallite. Degree of graphitization is determined from XRD results (Kim and Reneker 1999) by using formula (g = ((0.3440-d200)/(0.3440–0.3354)) × 100 and d200 = nλ/2sinθ where λ is wavelength, θ is diffraction angle and 0.3440 is interlayer spacing of fully non graphitized carbon (nm). Degree of graphitization for PAN nanofibers is −20 % and for PAN–CNT nanofibers is −41.86. Degree of graphitization increases due to presence of CNT in fibers.Fig. 7

Bottom Line: Also with stabilization, carbonization and graphitization diameter of nanofiber decreases.XRD results show that degree of graphitization increases on increasing CNT concentration because of additional stresses exerting on the nanofiber surface in the immediate vicinity of CNTs.TGA results shows wt loss decreases as CNT concentration increases in fibers.

View Article: PubMed Central - PubMed

Affiliation: Department of Physics, Krishna Institute of Engineering and Technology, Ghaziabad, India.

ABSTRACT
Electrospun fibrous membranes find place in diverse applications like sensors, filters, fuel cell membranes, scaffolds for tissue engineering, organic electronics etc. The objectives of present work are to electrospun polyacrylonitrile (PAN) nanofibers and PAN-CNT nanocomposite nanofibers and convert into carbon nanofiber and carbon-CNT composite nanofiber. The work was divided into two parts, development of nanofibers and composite nanofiber. The PAN nanofibers were produced from 9 wt% PAN solution by electrospinning technique. In another case PAN-CNT composite nanofibers were developed from different concentrations of MWCNTs (1-3 wt%) in 9 wt% PAN solution by electrospinning. Both types of nanofibers were undergone through oxidation, stabilization, carbonization and graphitization. At each stage of processing of carbon and carbon-CNT composite nanofibers were characterized by SEM, AFM, TGA and XRD. It was observed that diameter of nanofiber varies with processing parameters such as applied voltage tip to collector distance, flow rate of solution and polymer concentrations etc. while in case of PAN-CNT composite nanofiber diameter decreases with increasing concentration of CNT in PAN solution. Also with stabilization, carbonization and graphitization diameter of nanofiber decreases. SEM images shows that the minimum fiber diameter in case of 3 wt% of CNT solution because as viscosity increases it reduces the phase separation of PAN and solvent and as a consequence increases in the fiber diameter. AFM images shows that surface of film is irregular which give idea about mat type orientation of fibers. XRD results show that degree of graphitization increases on increasing CNT concentration because of additional stresses exerting on the nanofiber surface in the immediate vicinity of CNTs. TGA results shows wt loss decreases as CNT concentration increases in fibers.

No MeSH data available.


Related in: MedlinePlus