Abstract Due to outstanding properties, graphene and h-BN nanosheets are emerging as a potential candidate for wide spectrum of applications in the field of engineering and bio-medical science. Graphene and h-BN nanosheets have comparable mechanical and thermal properties, whereas due to high band gap h-BN (∼5eV) have contrasting electrical conductivities. Large size graphene and h-BN nanosheets are synthesized by chemical vapor deposition technique, which results in polycrystalline atomic structure. These polycrystalline nanosheets are characterized either by experimental means or numerical simulations. Experimental techniques are considered as most accurate and practical, but cost and time involved in these techniques limits it application at the nanoscale level. On the other hand, atomistic modeling techniques are emerging as viable alternatives to the experimentations, and are accurate enough to predict the mechanical properties, fracture toughness, and thermal conductivities of polycrystalline graphene and h-BN nanosheets. This comprehensive review article encompasses different characterizing techniques used by the researchers for polycrystalline nanosheets. This review will help in elaborating the properties of polycrystalline graphene and h-BN, and also establishing a perspective on how the microstructure impacts its large-scale physical properties.

中文翻译：

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双晶和多晶二维纳米材料的热机械性能综述

摘要 由于优异的性能，石墨烯和 h-BN 纳米片正在成为工程和生物医学科学领域广泛应用的潜在候选材料。石墨烯和 h-BN 纳米片具有相当的机械和热性能，而由于高带隙 h-BN（~5eV）具有对比的电导率。通过化学气相沉积技术合成大尺寸石墨烯和 h-BN 纳米片，从而形成多晶原子结构。这些多晶纳米片通过实验手段或数值模拟进行表征。实验技术被认为是最准确和实用的，但这些技术所涉及的成本和时间限制了它在纳米级的应用。另一方面，原子建模技术正在成为实验的可行替代方案，并且足够准确地预测多晶石墨烯和 h-BN 纳米片的机械性能、断裂韧性和热导率。这篇综合评论文章涵盖了研究人员用于多晶纳米片的不同表征技术。这篇综述将有助于阐述多晶石墨烯和 h-BN 的特性，并建立一个关于微观结构如何影响其大规模物理特性的观点。这篇综合评论文章涵盖了研究人员用于多晶纳米片的不同表征技术。这篇综述将有助于阐述多晶石墨烯和 h-BN 的特性，并建立一个关于微观结构如何影响其大规模物理特性的观点。这篇综合评论文章涵盖了研究人员用于多晶纳米片的不同表征技术。这篇综述将有助于阐述多晶石墨烯和 h-BN 的特性，并建立一个关于微观结构如何影响其大规模物理特性的观点。