Oxidative stabilization of polyacrylonitrile nanofibers and carbon nanofibers containing graphene oxide (GO): a spectroscopic and electrochemical study

Gergin, İlknur; İşmar, Ezgi; Sarac, A. Sezai̇

doi:10.3762/bjnano.8.161

Cited by 58 publications

(59 citation statements)

References 56 publications

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“…The T p of GP‐10 decreased by 11 °C than that of PAN. These results verified that GO could initiate the cyclization reaction of PAN at a lower temperature due to its functional groups …”

Section: Resultsmentioning

confidence: 90%

“…There are also entities which contain both cyclic and crosslinked units. In order to quantitatively analyze the crosslinking structure and cyclization structure in stabilized films, this structure was ignored in the solubility measurement . As shown in Figure (a,b), the stabilized films immersed in DMSO solvent had no obvious dissolution after 24 h. However, those immersed in H 2 SO 4 solution dissolved extensively.…”

Section: Resultsmentioning

confidence: 99%

“…The first was the initiation effect (Figure ). The electronegativity groups such as carboxylic groups on GO sheets could initiate the nucleophilic attack to nitrile group of PAN macromolecules during heat treatment . Thus, GO could take part in the cyclization reaction of PAN macromolecules .…”

Section: Resultsmentioning

confidence: 99%

“…During oxidative stabilization, oxygen diffusion and the amount of active ionic groups in PAN matrix are two important factors for the formation of cyclization structure and crosslinking structure. The ionic groups such as carboxyl, ester, and acylamino groups in comonomers can initiate the cyclization reaction during heat treatment . The oxygen diffusion is beneficial to the formation of crosslinked ladder structures in stabilized PAN materials …”

Section: Introductionmentioning

confidence: 99%

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Structure evolution mechanism of polyacrylonitrile films incorporated with graphene oxide during oxidative stabilization

Chen

et al. 2019

J of Applied Polymer Sci

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Oxidative stabilization is a key process for polyacrylonitrile (PAN)-based carbon materials. During this process, oxygen has a significant influence on the formation of cyclization structure and crosslinking structure of PAN matrix. Here, graphene oxide (GO) was used as filler in PAN matrix, the structure evolution of GO/PAN composite was studied during oxidative stabilization. Solubility measurement revealed that the crosslinking degree increased, while the cyclization degree of stabilized films decreased after GO incorporation. The effect of GO on the structure of PAN film was characterized by XRD, DSC, DMA, FTIR, and XPS. These results verified that GO could initiate the cyclization reaction of PAN at a lower temperature. The carboxylic groups on GO sheets might take part in the cyclization reactions during the heat treatment. Moreover, the oxygen-containing molecules released from GO decomposition during the heat treatment were beneficial to the formation of crosslinking structure. The possible mechanism of the structure evaluation was proposed in this article.

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“…The T p of GP‐10 decreased by 11 °C than that of PAN. These results verified that GO could initiate the cyclization reaction of PAN at a lower temperature due to its functional groups …”

Section: Resultsmentioning

confidence: 90%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Structure evolution mechanism of polyacrylonitrile films incorporated with graphene oxide during oxidative stabilization

Chen

et al. 2019

J of Applied Polymer Sci

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“…Firstly, it should be mentioned that nanofi brous mats with smaller amounts of casein in combination with a larger amount of PAN still showed a brownish colour aft er the carbonisation at 500 °C, indicating that the treatment temperature or duration were not suffi cient. Besides this fi nding, smaller amounts of casein (0.0 g or 0.1 g, respectively) resulted in relatively fi ne fi bres , 63(1), [38][39][40][41][42][43][44][45][46][47][48][49] , 63(1), [38][39][40][41][42][43][44][45][46][47][48][49] , 63(1), [38][39][40][41][42][43][44][45][46][47][48][49] , 63(1), [38][39][40][41][42][43][44][45][46][47][48][49] Figure 5b), the sample with 1.6 g PAN and 0.2 g casein was touchable without problems and even bendab...…”

Section: Chemical and Morphological Modifi Cation Of Pan Nanofi Brousmentioning

confidence: 77%

Chemical and Morphological Modification of PAN Nanofibrous Mats with Addition of Casein after

Diestelhorst¹,

Mance²,

Mamun³

et al. 2020

TEK

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Electrospun polyacrylonitrile (PAN) nanofi brous mats belong to typical precursor materials of carbon nanofibres. They have, however, the problem that they need to be fi xed or even stretched during stabilisation and ideally also during carbonisation in order to avoid undesired conglutinations and deformations of the original nanofi bre morphology, resulting in brittle behaviour of the macroscopic nanofi brous mat, which impedes several applications. In an earlier investigation, blending PAN with ZnO was shown to increase fi bre diameters and lead to unproblematic stabilisation and carbonisation of nanofi brous mats. ZnO, on the other hand, may have a negative impact on biotechnological applications such as tissue engineering. Here, we thus report on the morphological and chemical modifi cations due to blending PAN electrospinning solutions with diff erent amounts of casein. By optimising the PAN : casein ratio, relatively thick, straight nanofibres are obtained, which can be stabilised and carbonised unambiguously, without the well-known negative impact on cell adhesion due to the addition of ZnO.Elektropredene nanovlaknate koprene iz poliakrilonitrila (PAN) predstavljajo tipične prekurzorje za izdelavo ogljikovih nanovlaken. Med stabilizacijo in po možnosti tudi med karbonizacijo morajo biti pritrjene, da bi lahko preprečili neželeno zlepljenje in deformacijo prvotne nanovlaknate oblike, ki vodi v krhkost makroskopske nanovlaknate koprene in zmanjša možnosti njene uporabe. V predhodni raziskavi je bilo ugotovljeno, da mešanje PAN z ZnO vpliva na povečanje premera vlaken in omogoči stabilizacijo ter karbonizacijo nanovlaknatih kopren. ZnO pa lahko po drugi strani negativno vpliva na biotehnološke aplikacije, kot je tkivni inženiring. V članku so zato predstavljene morfološke in kemijske modifi kacije, ki so bile dosežene z uporabo predilnih raztopin za elektropredenje PAN z dodatkom različnih količin kazeina. Z optimizacijo razmerja PAN : kazein dobimo relativno debela, ravna nanovlakna, ki jih je moč stabilizirati in karbonizirati, brez da bi zaradi dodatka ZnO prišlo do dobro znanega negativnega vpliva na celično adhezijo.

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2D‐Topology‐Seeded Graphitization for Highly Thermally Conductive Carbon Fibers

et al. 2022

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expansion coefficient in a wide temperature range. [2] CFs can not only be used as efficient thermal-management materials to maintain the functionality and reliability of microelectronic components with high heat flux, but also be used as high-performance composites for thermal protection of flight devices in the aerospace field. [3] In spite of their wide uses, the specific pitch-based CFs are the only commercial species of highly thermally conductive CFs with high cost. [4] As a comparison, the other commercial PAN-based CFs have strong mechanical properties but poor thermal conductivity due to their limited graphitic crystallinity, determining their confined application as lightweight structural materials. [2a,5] In this context, it is necessary to expand alternative sources of highly thermally conductive fibers beyond the sole pitch-based CFs. [2b,6] An intuitive option is translating PAN-based CFs to highly thermally conductive species, but remains a forbidden task that is challenged by the intrinsic incompatibility between the 1D topology of linear polymers and the 2D topology of target graphitic crystallinity. [5b,7] The thermal conductivity of graphitic materials is determined by their complicated nano textures and spans a wide range from ≈6 W m −1 K −1 in glassy carbon to ≈2000 W m −1 K −1 in pyrolytic graphite at room temperature. [8] In principle, the Highly thermally conductive carbon fibers (CFs) have become an important material to meet the increasing demand for efficient heat dissipation. To date, high thermal conductivity has been only achieved in specific pitch-based CFs with high crystallinity. However, obtaining high graphitic crystallinity and high thermal conductivity beyond pitch-CFs remains a grand challenge. Here, a 2D-topology-seeded graphitization method is presented to mediate the topological incompatibility in graphitization by seeding 2D graphene oxide (GO) sheets into the polyacrylonitrile (PAN) precursor. Strong mechanical strength and high thermal conductivity up to 850 W m −1 K −1 are simultaneously realized, which are one order of magnitude higher in conductivity than commercial PAN-based CFs. The self-oxidation and seeded graphitization effect generate large crystallite size and high orientation to far exceed those of conventional CFs. Topologically seeded graphitization, verified in experiments and simulations, allows conversion of the non-graphitizable into graphitizable materials by incorporating 2D seeds. This method extends the preparation of highly thermally conductive CFs, which has great potential for lightweight thermal-management materials.

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Oxidative stabilization of polyacrylonitrile nanofibers and carbon nanofibers containing graphene oxide (GO): a spectroscopic and electrochemical study

Cited by 58 publications

References 56 publications

Structure evolution mechanism of polyacrylonitrile films incorporated with graphene oxide during oxidative stabilization

Structure evolution mechanism of polyacrylonitrile films incorporated with graphene oxide during oxidative stabilization

Chemical and Morphological Modification of PAN Nanofibrous Mats with Addition of Casein after

2D‐Topology‐Seeded Graphitization for Highly Thermally Conductive Carbon Fibers

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