Self-assembly and alignment of nanowires for flexible composite materials with anisotropic electrical and optical properties

Liyiming Tao^*, Zechao Jiang^#, Xinkun Man^#, Ye Xu^*

^* School of Mechanical Engineering and Automation, Beihang University, Beijing, China (ye.xu@buaa.edu.cn)

^# School of Physics, Beihang University, Beijing, China

Abstract

Metallic nanowires have been widely used in flexible electronics. The large aspect ratio of nanowires allows them to form percolating networks at a very low concentration, which is beneficial for flexible and transparent electrodes. However, the advantage of the one-dimensional (1D) characteristics of nanowires has not been fully utilized. In this talk, I will present our recent work in the self-assembly and alignment of silver nanowires (AgNWs) using external fields including fluid flow and electrical current, to achieve composite materials with anisotropic electrical and optical properties. First, we use a shear flow to prepare silver nanowire networks with various degree of alignment.  We established a relation among shear rates, degree of alignment, and electrical and optical anisotropy in silver nanowire networks [1].  Second, by adding polymeric components into the suspension containing AgNWs, we can control the alignment direction of AgNWs near the evaporation edge. Our work provides a new processing method for nanocomposites with anisotropic properties. 

References

[1] Xu, Y.; Ge, D. et al.: Highly conductive and transparent coatings from flow-aligned silver nanowires with large electrical and optical anisotropy. Nanoscale, Vol. 12, pp. 6438-6448, 2020.