Two-dimensional carbon nanocomposites (TDCN) are assembled by two-dimensional carbon nanosheets and show promising applications in many fields such as unmanned aerial vehicles, aerospace, and smart wearable devices due to their exceptional performance including light weight, high strength, high electrical and thermal conductivities, etc. Compared with traditional carbon-fiber-reinforced composites, two-dimensional carbon nanosheets represented by graphene and titanium carbide (MXene) have outstanding mechanical properties, making them ideal candidates for fabricating high-performance nanocomposites. Over the past two decades, many researchers have developed many strategies to solve intrinsic issues in the fabrication of TDCN, such as poor dispersion, low orientation, weak interfacial interactions, etc. Although many achievements in mechanical properties of TDCN have been obtained, the mechanical performance of TDCN is still far below theoretical expectations based on the intrinsic performance of two-dimensional carbon nanosheets. We first found that there is an important issue ignored so far, void, resulting in low load transfer efficiency in TDCN. Recently, the investigations about voids’ characterization, analysis, and elimination have been demonstrated as a key scientific issue for further enhancing the performance of TDCN.

中文翻译：

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二维碳纳米复合材料中空隙的发现和消除策略

二维碳纳米复合材料（TDCN）由二维碳纳米片组装而成，具有轻质、高强、高电性能等优异性能，在无人机、航空航天、智能可穿戴设备等领域显示出广阔的应用前景。与传统的碳纤维增强复合材料相比，以石墨烯和碳化钛（MXene）为代表的二维碳纳米片具有优异的机械性能，使其成为制造高性能纳米复合材料的理想选择。在过去的二十年里，许多研究人员开发了许多策略来解决TDCN制备中的固有问题，例如分散性差、取向性低、界面相互作用弱等。尽管在TDCN的力学性能方面取得了许多成果，但力学性能TDCN的性能仍然远远低于基于二维碳纳米片的固有性能的理论预期。我们首先发现有一个至今被忽视的重要问题，即void，导致TDCN的负载转移效率低。最近，有关空洞表征、分析和消除的研究已被证明是进一步提高 TDCN 性能的关键科学问题。