Highly efficient patterning technique for silver nanowire electrodes by electrospray deposition and its application to self-powered triboelectric tactile sensor

Abstract

A patterned transparent electrode is a crucial component of state-of-the-art wearable devices and optoelectronic devices. However, most of the patterning methods using silver nanowires (AgNWs), which is one of the outstanding candidate materials for the transparent electrode, wasted a large amount of unused AgNWs during the patterning process. Here, we report a highly efficient patterning of AgNWs using electrospray deposition with grounded electrolyte solution (EDGE). During electrospray deposition, a patterned electrolyte solution collector attracted AgNWs by strong electrostatic attraction and selectively deposited them only on the patterned collector, minimizing AgNW deposited elsewhere. The enhanced patterning efficiency was verified through a comparison between the EDGE and conventional process by numerical simulation and experimental validation. As a result, despite the same electrospray deposition conditions for both cases except for the existence of the electrolyte solution collector, the coverage ratio of AgNWs fabricated by the EDGE process was at least six times higher than that of AgNWs produced by the conventional process. Furthermore, the EDGE process provided high design flexibility in terms of not only the material of the substrate, including a polymer and a ceramic but also the shape of the substrate, including a 2D flat and 3D curved surface. As an application of the EDGE process, a self-powered touch sensor exploiting the triboelectric effect was demonstrated. Thus, the EDGE process would be utilized in further application in wearable or implantable devices in the field of biomedicine, intelligent robots, and human–machine interface.

Facile fabrication of large-scale silver nanowire transparent conductive films by screen printing

“…Nevertheless, some defects restrict the commercial application of AgNW TCFs, including difficulty in largescale production, personalized pattern and precision printing [25,26]. Currently, ultrasonic spray coating [27][28][29][30], spin coating [21], slot coating [31][32][33] and screen printing [7,[34][35][36][37][38][39][40][41][42][43][44] have been used for the large-scale production of high-quality TCFs. Wherein, ultrasonic spraying as an efficient method to produce large-sized TCFs, while it has to face with defects such as high surface roughness and poor uniformity.…”

Electrode materials for stretchable triboelectric nanogenerator in wearable electronics

“…Though there are tribomaterials with transparent properties, electrodes with considerable transparency, conductivity and easily patternable are least reported. Song et al , 86 successfully deposited patterned Ag NWs using electrospray deposition with grounded electrolyte solution (EDGE). The technique allows the selective deposition of Ag NWs on grounded electrolyte solution of specified pattern, reducing overall Ag NW leakage elsewhere.…”

On-demand ferrofluid droplet formation with non-linear magnetic permeability in the presence of high non-uniform magnetic fields

“…The dynamics of droplet formation has been investigated numerically, experimentally, and theoretically in different geometries, including nozzles 1 and lab-on-a-chip systems 2 . Droplet generation has been utilized in various applications, such as 3D printing 3 , electrosprays 4 , and bioengineering 5 . Droplet formation is performed by passive 6 or active 7 methods, which differ in the absence or presence of an external force.…”