The development of nanoscale reinforcements, which can tailor the interfacial strength and impart multiple functionalities on carbon fiber reinforced polymer (CFRP) composites, remains a challenge for their large-scale adoption in diverse applications ranging from aerospace to transportation and construction industries. In this work radially aligned graphene nanoflakes (GNFs), grown directly on carbon fibers (CFs) via a simple one-step microwave plasma enhanced chemical vapor deposition method, without any catalyst, were used as a novel nano-reinforcement interface. A remarkable 28% enhancement in the tensile strength of the hybrid fibers was observed via single-fiber tensile strength tests, whereas the interfacial shear strength (IFSS) increased by 101.5%. Our results demonstrate that GNFs not only improve the interfacial strength between the GNFs and the epoxy resin but also enhance the in-plane mechanical strength of the CFs—a well-known problem encountered with the direct growth of carbon nanotubes on CFs. In addition, GNFs provided embedded functionality via increased electrical conductivity (60.5% improvement for yarns and 16% for single fiber) and electrochemical capacitance (157% for yarns). This work indicates the potential of GNFs as an interphase for the simplified and cost-effective production of stronger multifunctional CFRP composite materials.

中文翻译：

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碳纤维上径向生长的石墨烯纳米薄片作为聚合物复合材料的增强界面

纳米级增强材料的开发可以调整界面强度并赋予碳纤维增强聚合物（CFRP）复合材料多种功能，对于在航空航天，交通运输和建筑行业等各种应用中大规模采用它们仍然是一个挑战。在这项工作中，通过简单的一步式微波等离子体增强化学气相沉积法直接在碳纤维（CFs）上生长的径向排列的石墨烯纳米薄片（GNF），无需任何催化剂，就被用作新型的纳米增强界面。通过单纤维拉伸强度测试观察到杂化纤维的拉伸强度显着提高了28％，而界面剪切强度（IFSS）提高了101.5％。我们的结果表明，GNF不仅可以改善GNF与环氧树脂之间的界面强度，而且可以增强CF的面内机械强度-这是在CF上直接生长碳纳米管时遇到的众所周知的问题。此外，GNF通过提高电导率（纱线提高60.5％，单纤维提高16％）和电化学电容（纱线提高157％）提供嵌入式功能。这项工作表明，GNF作为中间相的潜力，可以简化且经济高效地生产功能更强的多功能CFRP复合材料。GNF通过提高电导率（纱线提高60.5％，单纤维提高16％）和电化学电容（纱线提高157％）提供嵌入式功能。这项工作表明，GNF作为中间相的潜力，可以简化且经济高效地生产功能更强的多功能CFRP复合材料。GNF通过提高电导率（纱线提高60.5％，单纤维提高16％）和电化学电容（纱线提高157％）提供嵌入式功能。这项工作表明，GNF作为中间相的潜力，可以简化且经济高效地生产功能更强的多功能CFRP复合材料。