title: Direct-Write, Self-Aligned Electrospinning on Paper for Controllable Fabrication of Three-Dimensional Structures.
abstract: Electrospinning, a process that converts a solution or melt droplet into an ejected jet under a high electric field, is a well-established technique to produce one-dimensional (1D) fibers or two-dimensional (2D) randomly arranged fibrous meshes. Nevertheless, the direct electrospinning of fibers into controllable three-dimensional (3D) architectures is still a nascent technology. Here, we apply near-field electrospinning (NFES) to directly write arbitrarily shaped 3D structures through consistent and spatially controlled fiber-by-fiber stacking of polyvinylidene fluoride (PVDF) fibers. An element central to the success of this 3D electrospinning is the use of a printing paper placed on the grounded conductive plate and acting as a fiber collector. Once deposited on the paper, residual solvents from near-field electrospun fibers can infiltrate the paper substrate, enhancing the charge transfer between the deposited fibers and the ground plate via the fibrous network within the paper. Such charge transfer grounds the deposited fibers and turns them into locally fabricated electrical poles, which attract subsequent in-flight fibers to deposit in a self-aligned manner on top of each other. This process enables the design and controlled fabrication of electrospun 3D structures such as grids, walls, hollow cylinders, and other 3D logos. As such, this technique has the potential to advance the existing electrospinning technologies in constructing 3D structures for biomedical, microelectronics, and MEMS/NMES applications.
authors.affiliation: College of Optoelectronic Engineering, Chongqing University , Chongqing 400044, China.|Department of Mechanical Engineering, University of California , Berkeley, California 94720, United States.
authors.forename: Guoxi
authors.initials: G
authors.lastname: Luo
authors.affiliation: Department of Mechanical Engineering, University of California , Berkeley, California 94720, United States.|School of Engineering, San Francisco State University , San Francisco, California 94132, United States.
authors.forename: Kwok Siong
authors.initials: KS
authors.lastname: Teh
authors.affiliation: Department of Mechanical Engineering, University of California , Berkeley, California 94720, United States.
authors.forename: Yumeng
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Mechanical Engineering, University of California , Berkeley, California 94720, United States.
authors.forename: Xining
authors.initials: X
authors.lastname: Zang
authors.affiliation: College of Optoelectronic Engineering, Chongqing University , Chongqing 400044, China.
authors.forename: Zhiyu
authors.initials: Z
authors.lastname: Wen
authors.affiliation: Department of Mechanical Engineering, University of California , Berkeley, California 94720, United States.
authors.forename: Liwei
authors.initials: L
authors.lastname: Lin
keywords: 3D electrospinning; 3D micro-/nanofabrications; direct-write; near-field electrospinning; self-alignment