Carbon nanofiber having embedded carbon nanotubes, and method of manufacture
AssigneeCence Inc.
InventorsSunshine Holmberg, Stoyan Atanassov Radkov
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Abstract
A method of producing Stress Activated Pyrolytic Carbon-Carbon NanoTube (SAPC-CNT) fibers is disclosed. The fibers are a composite consisting of a tubular core of pristine graphite planes that include carbon nanotubes (CNTs) surrounded by semi-graphitic carbon material that includes Stress Activated Pyrolytic Carbon (SAPC), the SAPC being characterized by wavy graphite planes ranging from 0.1 nm to 1 nm and oriented parallel to the axis of each fiber, the semi-graphitic carbon material also being characterized by an inclusion of 4 to 10 atomic percent of nitrogen heteroatoms, the nitrogen heteroatoms including an above 60% of quaternary and pyridinic nitrogen groups.
Claims16
A method of producing one or more Stress Activated Pyrolytic Carbon-Carbon NanoTube (SAPC-CNT) fibers, the fibers being a composite consisting of a tubular core of pristine graphite planes that include carbon nanotubes (CNTs) surrounded by semi-graphitic carbon material that includes Stress Activated Pyrolytic Carbon (SAPC), the SAPC being characterized by wavy graphite planes ranging from 0.1 nm to 1 nm and oriented parallel to the axis of each fiber, the semi-graphitic carbon material also being characterized by an inclusion of 4 to 10 atomic percent of nitrogen heteroatoms, the nitrogen heteroatoms including an above 60% of quaternary and pyridinic nitrogen groups, the method for producing the SAPC-CNT fibers comprising:
- preparing a Polyacrylonitrile (PAN) based precursor solution infused with CNTs to produce a PAN-CNT precursor;
- providing the PAN-CNT precursor solution to a spinneret;
- performing an electrospinning operation on the PAN-CNT precursor solution to create the one or more fibers, wherein the electrospinning operation includes passing the PAN-CNT-based precursor solution from the spinneret to a collector at a distance between 1 cm to 30 cm while providing an Alternating Current (AC) voltage between the spinneret and the collector, the AC voltage having a frequency ranging from 20 Hz to 100,000 Hz and either a Peak-to-Peak (P-P) voltage ranging from 100V to 30,000V or a Root-Mean-Square (RMS) voltage ranging from 100V to 30,000V;
- performing a post-electrospinning operation on the one or more fibers, the post-electrospinning operation including a mechanical treatment and a chemical treatment;
- performing a stabilizing treatment on the one or more fibers, the stabilizing treatment including heating the one or more fibers;
- and
- after performing the post-electrospinning operation and stabilizing treatment, performing a pyrolysis treatment on the one or more fibers, the pyrolysis treatment including heating the one or more fibers in an inert atmosphere containing less than 1% oxygen.
The method of producing one or more SAPC-CNT fibers of claim wherein
- the electrospinning operation is performed in an ambient atmosphere at a temperature ranging from 10° C. to 100° C. with minimum humidity 45%.
A method of producing one or more Stress Activated Pyrolytic Carbon-Carbon NanoTube (SAPC-CNT) based fibers, the fibers being a composite consisting of a tubular core of pristine graphite planes that include carbon nanotubes (CNTs) surrounded by semi-graphitic carbon material that includes Stress Activated Pyrolytic Carbon (SAPC), the SAPC being characterized by wavy graphite planes ranging from 0.1 nm to 1 nm and oriented parallel to the axis of each fiber, the semi-graphitic carbon material also being characterized by an inclusion of 4 to 10 atomic percent of nitrogen heteroatoms, the nitrogen heteroatoms including an above 60% of quaternary and pyridinic nitrogen groups, the method for producing the SAPC-CNT fibers comprising:
- preparing a Polyacrylonitrile (PAN) based precursor solution infused with CNTs to produce a PAN-CNT precursor;
- providing the PAN-CNT precursor solution to a spinneret;
- performing an electrospinning operation on the PAN-CNT-based precursor solution to create the one or more fibers, wherein the electrospinning operation includes passing the PAN-CNT-based precursor solution from the spinneret to a collector while providing an Alternating Current (AC) voltage between the spinneret and the collector, the AC voltage having a frequency ranging from 1 Hz to 100,000 Hz and either a Peak-to-Peak (P-P) voltage ranging from 100V to 30,000V or a Root-Mean-Square (RMS) voltage ranging from 100V to 30,000V;
- performing a post-electrospinning operation on the one or more fibers, the post-electrospinning operation including a mechanical treatment and a chemical treatment;
- performing a stabilizing treatment on the one or more fibers, the stabilizing treatment including heating the one or more fibers;
- and
- after performing the post-electrospinning operation and stabilizing treatment, performing a pyrolysis treatment on the one or more fibers, the pyrolysis treatment including heating the one or more fibers in an oxygen-free atmosphere.
Dependencies are inferred from the claim text.