Zhejiang University and Tsinghua University "Adv. Funct. Mater": Plastic spinning to prepare high-strength and conductive high-crystalline graphene

Article source: Material analysis and application? Graphene fiber (GF) is a macroscopic one-dimensional component of a single graphene sheet, with excellent mechanical properties and excellent versatility
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However, due to the unfavorable crystal structure, especially caused by the wrinkled conformation of graphene, the performance of graphene fibers is still limited
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In this article, the team of Professor Gao Chao and Xu Zhen of Zhejiang University and the team of Professor Ma Weigang of Tsinghua University (joint communication) published a paper titled "Highly Crystalline Graphene Fibers with Superior Strength and Conductivities by Plasticization Spinning" in the journal Advanced Functional Materials.
The study uses the previously established solvent intercalation plasticization effect to perform secondary plasticization and stretching of the nascent graphene oxide fiber, which greatly eliminates the random wrinkle structure in the graphene precursor
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After the subsequent high-temperature heat treatment, the graphene aligned straight along the fiber axis greatly promotes the crystal growth of the graphene's preferred orientation, resulting in a graphene fiber with a high degree of orientation and large-size graphite crystallites
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The orientation of the graphene fibers can reach 92%, and the size of the graphite crystallites is 174.
3 nm, which is much larger than that of the internal crystallites of traditional carbon fibers
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? The combination of high orientation and large crystals makes graphene fibers have both high strength (3.
4 GPa) and excellent electrical (1.
19′106 S/m) and thermal conductivity (1480 W/m K), which is to promote the integration of structure and function Carbon fiber provides new ideas
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This plasticized spinning process can realize continuous preparation, which is beneficial to the engineering of graphene fibers
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? Figure 1 Plasticizing spinning to prepare highly crystalline graphene fibers? Figure 2 Stress-strain curve of graphene oxide fiber plastic deformation, basic conditions of plasticization, and structural changes during plasticization and stretching
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Figure 3 Multi-stage plasticizing spinning process and the structure and properties of graphene fiber precursors? Figure 4 The crystalline structure of graphene fibers? Figure 5 The comprehensive properties of graphene fibers? This article provides a method for preparing graphene fiber with integrated structure and function.
Ideas and methods of olefin fibers
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Through the new understanding of the plasticizing effect of the graphene macroscopic assembly, highly oriented graphene fiber precursors were prepared, and the crystallization of the preferred orientation during the graphitization process was promoted, and highly ordered and highly crystalline graphene fibers were obtained
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This multi-stage plasticizing spinning method and process is convenient for large-scale enlargement
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