石墨烯纤维的结构调控及其与性能的关系研究

Graphene fiber (GF) is formed by the continuous assembly of individual graphene sheets along one-dimensional direction. GF was presented and invented by the applicant group, representing a novel kind of high performance, multifunctional carbonaceous fiber. GF has interesting attributes of high electrical conductivity, high thermal conductivity, and low density, showing great dual-use potentials. This proposal focuses on the systematic study on the structure control of GF and its structure-property relationship, aims to achieve original academic results, and paves the way to real application of GF. Firstly, fiber-level material of graphene oxide (GO) liquid crystal spinning dope is fast and safely produced in large-scale via a new iron-based method. Then wet-spinning of the liquid crystal dope, followed by chemical reduction, gives rise to continuous GFs. The fine structures of GF such as diameter, density, orientation, and distance between graphene sheets will be controlled through the parameters of GO, spinning process, and post-treatment. The influence of both graphene structure and assembled hieratical structures on the mechanical, electrical, thermal, and electromagnetic properties of GF will be investigated deeply and systematically. Based on the structure-property result, continuous and reproducible fabrication of GF single fibers and tows with light-weight, high electrical conductivity, and high toughness will be realized. This project will result in the whole novel technology system from the synthesis of raw material to the production of GFs. In addition, the GFs will be applied in the fields of electromagnetic fabrics and wearable electronics.

石墨烯纤维是石墨烯片沿轴向有序堆积排列而成的连续组装材料，是由申请者团队提出并率先制备的高性能多功能新型碳基纤维，具有高导电、高导热、低密度等特性，军民两用潜力巨大。项目针对石墨烯纤维的结构调控及结构与性能关系开展系统深入研究，力争取得原创性和系统性的学术研究成果，并为石墨烯纤维的实际应用打下基础。首先采用申请人发明的铁系氧化剂法快速、安全、宏量制备出纺丝级氧化石墨烯液晶原料，运用液晶湿纺策略及化学还原法形成连续石墨烯纤维。通过对原料、纺丝过程及工艺、纤维后处理等的控制优化实现纤维的直径、密度、取向度及片间距等聚集态结构的调控，研究石墨烯基元及组装多级结构与纤维的力学、电学、热学、电磁学等性能的关系。利用结构-性能关系的规律，实现轻质高导高韧等多功能石墨烯纤维单丝和丝束的连续稳定制备，建立从原料合成到纤维制备的全链条创新体系，探索石墨烯纤维在电磁屏蔽及柔性可穿戴电子器件方面的应用。

石墨烯纤维是由石墨烯基元沿轴向有序堆积排列而成的连续组装材料，具有高力学性能和多功能特性。本项目重点研究了石墨烯纤维的结构调控及结构与性能关系，取得了系列原创性和系统性的学术研究成果，为石墨烯纤维的高性能化及工程化打下基础。从大尺寸氧化石墨烯原料制备、氧化石墨烯液晶纺丝液、氧化石墨烯纤维的可控制备、石墨烯纤维低缺陷化处理、多尺度结构及性能表征等方面开展系统深入的研究。阐明了氧化石墨烯原料、液晶湿纺组装、液固相变以及低缺陷化处理过程中多级多尺度缺陷结构演变规律，建立了石墨烯基元及组装多级结构与纤维的力学、电学、热学等性能的关。提出了系列提高石墨烯纤维综合性能的原理和方法，包括全尺度协同缺陷工程、化学掺杂、溶剂塑化拉伸法。搭建石墨烯纤维丝束和融合石墨烯纤维无纺布制备系统，为规模化制备石墨烯纤维及工程应用奠定了坚实的基础。石墨烯纤维的导热率达1480 W/mK，导电率为1.2×106 S/m，力学强度达到了3.4 GPa，模量400 GPa。在石墨烯原料及组装材料的工程化制备方面取得了突破，建立了氧化石墨烯的宏量生产线，设计建成石墨烯纤维丝束示范线并实现连续稳定制备。通过本项目，建立了石墨烯纤维的制备方法学，加深了对石墨烯纤维结构和性能构效关系的认识，为进一步开展石墨烯纤维结构设计和优化石墨烯纤维制备工艺指明了方向。.项目执行期间发表经费标注的SCI 论文共78篇，包括Science Advances 2篇，Nature Communications 5篇，Advanced Materials 8篇，Accounts of Materials Research 1篇、Matter 1篇、Journal of the American Chemical Society 1篇。授权中国发明专利66项，授权美国专利1项，授权日本专利2项，完成78项专利权转让。