Micro/Nano-scale Direct Writing

Achieving high-resolution direct writing of micro and nano fibers for novel applications in sensor and composite fabrication.

Three-dimensional (3D) printing of micro/nano-scale structures with high resolution (sub-micron) and low cost is still a challenging work for the existing 3D printing techniques. Near-field electrospinning and near-field melt electrospinning is a viable technique to overcome existing limitations.

For example, in near-field melt electrospinning, a molten polymer jet is ejected from the needle tip and stabilized in the near-field region (several millimeters) subjected to an external high voltage. Then the molten jet is collected in a defined pattern on the substrate and solidifies. The process allows continuous direct writing due to the linear and stable jet trajectory in the electric near-field. The layer-by-layer stacking of fibers, or self-assembly effect, is attributed to the attraction force from the molten deposited fibers and accumulated negative charges.

We have explored the process control strategy using external electric fields to steer the polymer jet (You et al., 2020) (You et al., 2017). We demonstrated micro-scale 3D printing using near-field melt electrospinning (You et al., 2017). Recently, we explored the immersed electrohydrodynamic direct writing to achieve near field-electrospinning inside a liquid bath, so fiber morphology and registration can be controlled to direct print fiber-reinforced composites (Xu et al., 2023) (Xu et al., 2022).



  1. iehd_fiber.jpg
    Yunzhi Xu ,  Nathanial Buettner ,  and  Ping Guo
    MRS Communications, 2023


  1. wet_spinning.jpg
    Yunzhi Xu ,  Junior Ndayikengurukiye ,  Ange-Therese Akono ,  and  Ping Guo
    Manufacturing Letters, 2022


  1. electrospinning_traj.jpg
    Xiangyu You ,  Yang Yang ,  and  Ping Guo
    Journal of Manufacturing Science and Engineering, 2020


  1. NFES_jmp.jpg
    Xiangyu You ,  Chengcong Ye ,  and  Ping Guo
    Journal of Manufacturing Processes, 2017
  2. melt_3d.jpg
    Xiangyu You ,  Chengcong Ye ,  and  Ping Guo
    Journal of Micro and Nano-Manufacturing, 2017