Brush-paintable and highly stretchable Ag nanowire and PEDOT:PSS hybrid electrodes

Abstract

Highly transparent and stretchable Ag nanowire (NW)/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) hybrid electrodes were prepared on stretchable polyurethane substrates by using simple and cost-effective brush painting technique. The optimized Ag NW/PEDOT:PSS hybrid electrode showed a sheet resistance of 19.7 Ohm/square and a high optical transmittance of 88.64% comparable to conventional ITO electrode. It was found that shear stress of the paintbrush led to an effective lateral alignment of the Ag NWs into the PEDOT:PSS matrix during brush painting process. In addition, we investigated mechanical properties of the brush painted Ag NW/PEDOT:PSS hybrid electrode using inner/outer bending test, stretching tests, twisting test and rolling test in detail. The optimized brush painted Ag NW/PEDOT:PSS electrode showed a higher strain (~30%) than brush painted Ag NW or sputtered ITO electrode. Furthermore, we demonstrated the outstanding stretchability of brush painted Ag NW/PEDOT:PSS hybrid electrode in two applications: stretchable interconnectors and stretchable electrodes for stretchable and wearable thin film heaters. These results provide clear evidence for its potential and widespread applications in next-generation, stretchable displays, solar cells, and electronic devices.

Study of Brush-Painted Ag Nanowire Network on Flexible Invar Metal Substrate for Curved Thin Film Heater

“…As expected from sheet resistance, increasing number of brush painting increased Ag NW density, which is critically affected on the sheet resistance. In addition, connectivity between Ag NWs was improved by shear stress of the brush [28,30,31]. Based on sheet resistance of the Ag NW network electrode and surface morphology shown in picture, the optimal number of brush painting processes was found to be 2.…”

“…Recently simple printing processes, such as spin-coating, bar-coating, ink-jet, and brush-painting, have been paid much attention due to their handiness, rapidity, and affordability [26,27]. Among them, the brush-painting process is one of the most simple printing processes because it requires only simple tools like a painting brush and functional ink [28]. Specially, it can control film thickness from~10 nm to a few hundred nanometers and form polymer chains or one-dimensional nanostructure layers by shear stress.…”

“…Specially, it can control film thickness from~10 nm to a few hundred nanometers and form polymer chains or one-dimensional nanostructure layers by shear stress. In addition, it can be applied onto various flat and textured substrates [28]. Kim et al [29][30][31][32] have successfully reported the possibility of a fabricating organic thin film transistor and perovskite solar cells by means of the brush painting process.…”

“…We have also reported a successful fabrication of conductive electrode for organic solar cells based on the following materials: Ag nanowires (NW), poly(3,4-ethylenedioxylenethiophene):poly(styrene sulfonic acid) (PEDOT:PSS), Ti-doped In 2 O 3 nanoparticles, and Sn-doped In 2 O 3 nanoparticles [33][34][35][36][37]. Furthermore, we have successfully fabricated brush-painted stretchable electrode based on a polyurethane substrate by means of a composite of Ag NWs and PEDOT:PSS [28]. Therefore, brush-painted Ag NW on an invar substrate will able to play a significant role as a conductive electrode for curved TFHs.…”

Long wavy copper stretchable interconnects fabricated by continuous microcorrugation process for wearable applications

“…34 Wavy electrodes with centimeter scale large waves that were conductive polymer-coated bending fiber, 36 3D printed helical structure, 37,38 have been also constructed. However, the length of wavy electrodes is limited to several centimeters [33][34][35]39,40 because of the small rubber stretching machines and micromachining tools. Therefore, a continuous processing system to make long vertically wavy high conductive interconnects has been required especially for electronic textile applications.…”