Joule heating is featured with an extremely high rising rate of temperature with hundreds of kelvin per second, which has shown superiorities of high efficiency and energy conservation in graphene fabrication. Herein, we design a dynamic joule heating system for continuous synthesis of graphene fibers with ultrashort high-temperature (≈2000 °C), treating time (≈20 min), and low electric energy consumption (≈2000 kJ m⁻¹). During the joule heating fabrication, the current flowing through the fibers can manipulate the configuration of graphene sheets, the basic component units of fiber, and induce their alignment. Theoretical simulations reveal that graphene sheets tend to rotate towards the current direction under the current induced electric field for the highest stability with the lowest electric free energy and zero rotation torque. Therefore, the electrical and mechanical performances of as-fabricated graphene fibers can be further improved in comparison with thermally annealed graphene fibers without applying current.

中文翻译：

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石墨烯纤维焦耳加热过程中的电流对准元件单元

焦耳加热具有极高的升温速率，每秒数百开尔文，在石墨烯制造中显示出高效节能的优势。在此，我们设计了一种动态焦耳加热系统，用于连续合成具有超短高温（≈2000 °C）、处理时间（≈20 min）和低电能消耗（≈2000 kJ m ^{-1 ）的石墨烯纤维}）。在焦耳加热制造过程中，流过纤维的电流可以操纵石墨烯片（纤维的基本组成单元）的构型，并诱导它们的排列。理论模拟表明，石墨烯片在电流感应电场下倾向于向电流方向旋转，以获得最高的稳定性，最低的自由能和零旋转扭矩。因此，与未施加电流的热退火石墨烯纤维相比，制成的石墨烯纤维的电气和机械性能可以进一步提高。