中文摘要：

静电纺纳米纤维作为一种高技术、高附加值的纤维材料,在电子信息、环境治理、安全防护、组织工程等领域的应用已广泛展开.随着应用研究的不断深入,构建结构稳定的三维纤维材料已成为当前静电纺纤维应用性能提升的关键.近年来,科研人员已从溶液本体性质和制备方法2个方面进行了大量研究,通过逐层组装、辅助接收、外场优化等方法构建了多种三维纤维体型材料,并探索了其在组织工程等领域的应用.近期,研究人员提出了一种新型纤维三维网络重构方法,制备了超轻、超弹的纳米纤维气凝胶,为三维纤维材料的制备提供了新方法和新思路.本文在简要介绍静电纺丝技术及原理的基础上,综述了近年来三维构建方向的代表性进展,并对其未来发展进行了展望.

英文摘要：

Electrospun nanofibers, which are at the forefront of advanced fibrous materials, combine the robust mechanical strength, low density, fine flexibility, extremely high aspect ratio and ease of scalable synthesis from various materials, have been widely applied in the fields including electronics, environmental remediation, safety protections, and tissue engineering. Despite their outstanding potential, the major problem associated with electrospun nanofibers is their anisotropic lamellar deposition character, with the resultant nanofibers usually assembling into close-packed membranes（with thicknesses smaller than 100 mm） rather than into bulk threedimensional（3D） nanofibrous materials, which have restricted their widely applications. Thus, the construction of 3D nanofibrous materials with stable structures has become a key challenge for electrospun nanofibers. Currently, researchers have successfully fabricated various 3D nanofibrous materials based on different approaches. Herein, this review summarizes the recent representative literatures on 3D construction of electrospun nanofibers by using layer-by-layer stacking, liquid- or template-assisted collection, and condition optimization. In addition, the mechanism and latest development of each 3D construction method are briefly analyzed and reviewed. However, the principle of the aforementioned methods remains the direct deposition of nanofibers; thus, the anisotropic lamellar deposition problem of electrospun fibers has not been solved. Moreover, most of these products are not real 3D-structured aerogels but rather stacks of membranes or fluffy cotton-like nanofiber deposits, which exhibit poor mechanical strength with no elastic resilience. Therefore, we subsequently summarized a novel strategy for creating fibrous, isotropically bonded elastic reconstructed aerogels with a hierarchical cellular structure and superelasticity by combining electrospun nanofibers and the fibrous freeze-shaping technique. The premise for this design is that for the first t