Graphene Nanoplatelet (GNPs) Doped Carbon Nanofiber (CNF) System: Effect of GNPs on the Graphitic Structure of Creep Stress and Non-Creep Stress Stabilized Polyacrylonitrile (PAN)
Improving the graphitic structure in carbon nanofibers (CNFs) is important for exploiting their potential in mechanical, electrical and electrochemical applications. Typically, the synthesis of carbon fibers with a highly graphitized structure demands a high temperature of almost 2500 °C. F...
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2020-02-01
|
| Series: | Nanomaterials |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2079-4991/10/2/351 |
| _version_ | 1818143025178607616 |
|---|---|
| author | Annas Bin Ali Franz Renz Julian Koch Christoph Tegenkamp Ralf Sindelar |
| author_facet | Annas Bin Ali Franz Renz Julian Koch Christoph Tegenkamp Ralf Sindelar |
| author_sort | Annas Bin Ali |
| collection | DOAJ |
| description | Improving the graphitic structure in carbon nanofibers (CNFs) is important for exploiting their potential in mechanical, electrical and electrochemical applications. Typically, the synthesis of carbon fibers with a highly graphitized structure demands a high temperature of almost 2500 °C. Furthermore, to achieve an improved graphitic structure, the stabilization of a precursor fiber has to be assisted by the presence of tension in order to enhance the molecular orientation. Keeping this in view, herein we report on the fabrication of graphene nanoplatelets (GNPs) doped carbon nanofibers using electrospinning followed by oxidative stabilization and carbonization. The effect of doping GNPs on the graphitic structure was investigated by carbonizing them at various temperatures (1000 °C, 1200 °C, 1500 °C and 1700 °C). Additionally, a stabilization was achieved with and without constant creep stress (only shrinkage stress) for both pristine and doped precursor nanofibers, which were eventually carbonized at 1700 °C. Our findings reveal that the GNPs doping results in improving the graphitic structure of polyacrylonitrile (PAN). Further, in addition to the templating effect during the nucleation and growth of graphitic crystals, the GNPs encapsulated in the PAN nanofiber matrix act in-situ as micro clamp units performing the anchoring function by preventing the loss of molecular orientation during the stabilization stage, when no external tension is applied to nanofiber mats. The templating effect of the entire graphitization process is reflected by an increased electrical conductivity along the fibers. Simultaneously, the electrical anisotropy is reduced, i.e., the GNPs provide effective pathways with improved conductivity acting like bridges between the nanofibers resulting in an improved conductivity across the fiber direction compared to the pristine PAN system. |
| first_indexed | 2024-12-11T11:25:06Z |
| format | Article |
| id | doaj.art-37c136cacd3944f3ada4f18105caddef |
| institution | Directory Open Access Journal |
| issn | 2079-4991 |
| language | English |
| last_indexed | 2024-12-11T11:25:06Z |
| publishDate | 2020-02-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Nanomaterials |
| spelling | doaj.art-37c136cacd3944f3ada4f18105caddef2022-12-22T01:09:02ZengMDPI AGNanomaterials2079-49912020-02-0110235110.3390/nano10020351nano10020351Graphene Nanoplatelet (GNPs) Doped Carbon Nanofiber (CNF) System: Effect of GNPs on the Graphitic Structure of Creep Stress and Non-Creep Stress Stabilized Polyacrylonitrile (PAN)Annas Bin Ali0Franz Renz1Julian Koch2Christoph Tegenkamp3Ralf Sindelar4Institut für Anorganische Chemie, Leibniz Universität Hannover, Callinstr. 7, 30167 Hannover, GermanyInstitut für Anorganische Chemie, Leibniz Universität Hannover, Callinstr. 7, 30167 Hannover, GermanyInstitut für Festkörperphysik, Leibniz Universität Hannover, Appelstraße 2, 30167 Hannover, GermanyHannover School for Nanotechnology, Laboratorium für Nano und Quantenengineering (LNQE), Leibniz Universität Hannover, Schneiderberg 39, 30167 Hannover, GermanyHannover School for Nanotechnology, Laboratorium für Nano und Quantenengineering (LNQE), Leibniz Universität Hannover, Schneiderberg 39, 30167 Hannover, GermanyImproving the graphitic structure in carbon nanofibers (CNFs) is important for exploiting their potential in mechanical, electrical and electrochemical applications. Typically, the synthesis of carbon fibers with a highly graphitized structure demands a high temperature of almost 2500 °C. Furthermore, to achieve an improved graphitic structure, the stabilization of a precursor fiber has to be assisted by the presence of tension in order to enhance the molecular orientation. Keeping this in view, herein we report on the fabrication of graphene nanoplatelets (GNPs) doped carbon nanofibers using electrospinning followed by oxidative stabilization and carbonization. The effect of doping GNPs on the graphitic structure was investigated by carbonizing them at various temperatures (1000 °C, 1200 °C, 1500 °C and 1700 °C). Additionally, a stabilization was achieved with and without constant creep stress (only shrinkage stress) for both pristine and doped precursor nanofibers, which were eventually carbonized at 1700 °C. Our findings reveal that the GNPs doping results in improving the graphitic structure of polyacrylonitrile (PAN). Further, in addition to the templating effect during the nucleation and growth of graphitic crystals, the GNPs encapsulated in the PAN nanofiber matrix act in-situ as micro clamp units performing the anchoring function by preventing the loss of molecular orientation during the stabilization stage, when no external tension is applied to nanofiber mats. The templating effect of the entire graphitization process is reflected by an increased electrical conductivity along the fibers. Simultaneously, the electrical anisotropy is reduced, i.e., the GNPs provide effective pathways with improved conductivity acting like bridges between the nanofibers resulting in an improved conductivity across the fiber direction compared to the pristine PAN system.https://www.mdpi.com/2079-4991/10/2/351polyacrylonitrilegraphene nanoplateletsstabilizationcarbonizationshrinkage stresscreep stressgraphitizationelectrical anisotropy |
| spellingShingle | Annas Bin Ali Franz Renz Julian Koch Christoph Tegenkamp Ralf Sindelar Graphene Nanoplatelet (GNPs) Doped Carbon Nanofiber (CNF) System: Effect of GNPs on the Graphitic Structure of Creep Stress and Non-Creep Stress Stabilized Polyacrylonitrile (PAN) Nanomaterials polyacrylonitrile graphene nanoplatelets stabilization carbonization shrinkage stress creep stress graphitization electrical anisotropy |
| title | Graphene Nanoplatelet (GNPs) Doped Carbon Nanofiber (CNF) System: Effect of GNPs on the Graphitic Structure of Creep Stress and Non-Creep Stress Stabilized Polyacrylonitrile (PAN) |
| title_full | Graphene Nanoplatelet (GNPs) Doped Carbon Nanofiber (CNF) System: Effect of GNPs on the Graphitic Structure of Creep Stress and Non-Creep Stress Stabilized Polyacrylonitrile (PAN) |
| title_fullStr | Graphene Nanoplatelet (GNPs) Doped Carbon Nanofiber (CNF) System: Effect of GNPs on the Graphitic Structure of Creep Stress and Non-Creep Stress Stabilized Polyacrylonitrile (PAN) |
| title_full_unstemmed | Graphene Nanoplatelet (GNPs) Doped Carbon Nanofiber (CNF) System: Effect of GNPs on the Graphitic Structure of Creep Stress and Non-Creep Stress Stabilized Polyacrylonitrile (PAN) |
| title_short | Graphene Nanoplatelet (GNPs) Doped Carbon Nanofiber (CNF) System: Effect of GNPs on the Graphitic Structure of Creep Stress and Non-Creep Stress Stabilized Polyacrylonitrile (PAN) |
| title_sort | graphene nanoplatelet gnps doped carbon nanofiber cnf system effect of gnps on the graphitic structure of creep stress and non creep stress stabilized polyacrylonitrile pan |
| topic | polyacrylonitrile graphene nanoplatelets stabilization carbonization shrinkage stress creep stress graphitization electrical anisotropy |
| url | https://www.mdpi.com/2079-4991/10/2/351 |
| work_keys_str_mv | AT annasbinali graphenenanoplateletgnpsdopedcarbonnanofibercnfsystemeffectofgnpsonthegraphiticstructureofcreepstressandnoncreepstressstabilizedpolyacrylonitrilepan AT franzrenz graphenenanoplateletgnpsdopedcarbonnanofibercnfsystemeffectofgnpsonthegraphiticstructureofcreepstressandnoncreepstressstabilizedpolyacrylonitrilepan AT juliankoch graphenenanoplateletgnpsdopedcarbonnanofibercnfsystemeffectofgnpsonthegraphiticstructureofcreepstressandnoncreepstressstabilizedpolyacrylonitrilepan AT christophtegenkamp graphenenanoplateletgnpsdopedcarbonnanofibercnfsystemeffectofgnpsonthegraphiticstructureofcreepstressandnoncreepstressstabilizedpolyacrylonitrilepan AT ralfsindelar graphenenanoplateletgnpsdopedcarbonnanofibercnfsystemeffectofgnpsonthegraphiticstructureofcreepstressandnoncreepstressstabilizedpolyacrylonitrilepan |