Cu2+/polyacrylonitrile composite fibers were prepared by electrospinning, and then Cu/carbon nanofibers (denoted as Cu/ CNF-X; X = Cu content, 0, 3, or 5 wt%) were formed by calcining them. The effects of Cu2+ content and carbonization temperature on the conductivity and electrothermal conversion of Cu/CNF-X were investigated. The results revealed that the conductivity and electrothermal properties of Cu/CNF-X improve with the increase in the Cu2+ content and carbonization temperature. When the carbonization temperature was 800, 900, or 1000 °C, the conductivity of Cu/CNF-5 (0.08, 0.68, or 2.48 S/cm, respectively) increased to 1.6, 1.5, or 1.6 times that of Cu/CNF-0, respectively. The highest instantaneous surface temperatures of Cu/CNF-5 calcined at 800, 900, and 1000 °C (36, 145, and 270.2 °C, respectively) increased by 4, 25.5, and 44.6 °C, respectively, compared with those of the corresponding Cu/CNF-0 samples (32, 120.3, and 225.6 °C, respectively). Thus, the addition of a small amount of Cu2+ effectively improved the conductivity and electrothermal conversion performance of Cu/CNF-X, which has potential application value in industrial products in the future.

Effect of metallic copper on the electrothermal properties of carbon nanofibers
    Abstract
    1 Introduction
    2 Materials and methods
        2.1 Materials
        2.2 Sample preparation
            2.2.1 Preparation of the electrospinning solution
            2.2.2 Electrospinning conditions
            2.2.3 Pre-oxidation
            2.2.4 Carbonization
        2.3 Characterization
    3 Results and discussion
        3.1 Chemical structure of CuCNF-X
        3.2 Surface morphology and elemental composition of CuCNF-X
        3.3 Conductivity of CuCNF-X
        3.4 Surface temperature of CuCNF-X
    4 Conclusion
    Acknowledgements 
    References

• He‑Dong Huang(College of Materials Science and Art Design, Inner Mongolia Agricultural University, Hohhot 010018, China)
• Hao Pu(College of Materials Science and Art Design, Inner Mongolia Agricultural University, Hohhot 010018, China)
• Jun‑Wei Fan(College of Materials Science and Art Design, Inner Mongolia Agricultural University, Hohhot 010018, China)
• Bing Su(College of Materials Science and Art Design, Inner Mongolia Agricultural University, Hohhot 010018, China)
• Hong‑Yang Liu(College of Materials Science and Art Design, Inner Mongolia Agricultural University, Hohhot 010018, China)
• Xin‑Yi Ha(College of Materials Science and Art Design, Inner Mongolia Agricultural University, Hohhot 010018, China)
• Yong‑Fei Ren(Inner Mongolia Yuan Long Yong Tai Energy Technology Co. Ltd, Ordos 017000, China)
• Ze‑yu Guo(College of Materials Science and Art Design, Inner Mongolia Agricultural University, Hohhot 010018, China)