石墨烯纤维具有优异的力学、热学和电学性能，在航空航天、汽车、储能和催化等领域都具有潜在的应用前景。然而，与碳纤维相比，目前石墨烯纤维的力学性能还较低，极大地限制了其应用与发展。因此，增强石墨烯纤维的力学性能已成为石墨烯纤维研究领域的核心问题。针对这一核心科学问题，本项目拟首先建立石墨烯纤维的微观理论模型并对其进行微结构设计，增强石墨烯纤维的力学性能并兼顾较好的热学性能；接着基于分子动力学法，研究微结构变化对石墨烯纤维力学和热学性能影响的规律，探清多种相互作用间的协同效应，重点揭示力学性能提升的物理和化学机理；然后研究石墨烯纤维制备工艺对其力学性能的影响，改进和优化制备工艺；最后对石墨烯纤维进行实验和表征分析，并与理论分析的结果进行对比验证；最终建立石墨烯纤维微结构设计、理论分析、材料制备和实验测试的系统性体系。

Graphene fiber possesses excellent mechanical, thermal and electrical properties. It has potential applications in aerospace, automotive, energy storage and catalysis etc. However, compared with carbon fiber, the mechanical properties of graphene fiber at the current stage are still poor, which greatly limits its applications and developments. Therefore, improving the mechanical properties of the graphene fiber has become a critical issue in the field of graphene fiber research. To address this critical scientific issue, this project intends to first establish microscopic theoretical models for the mechanical properties of graphene fiber, and design the microstructure of the graphene fiber to enhance its mechanical properties and maintain superior thermal performances. Then, based on the molecular dynamics method, the effects of microstructure changes on the mechanical and thermal properties of graphene fibers will be studied. First, we will explore the synergetic effects between various interactions, and focus on revealing the physical and chemical mechanisms of mechanical property improvements; second, we will examine the influence of the preparation conditions on the mechanical properties of graphene fibers, and in turn optimize the preparation processing; third, we will measure the mechanical properties of graphene fibers and characterize, and compare with the theoretical analysis results. Finally, a systematic system for the graphene fibers via microstructure design, theoretical analysis, material preparation and experimental testing will be obtained.