Uniform Silver Nanowire Patterned Electrode on Robust PEN Substrate Using Poly(2-hydroxyethyl methacrylate) Underlayer

Abstract

Silver nanowire (AgNW) electrodes are among the most essential flexible transparent electrodes (FTEs) emerging as promising alternatives to brittle indium tin oxide (ITO) electrodes. The polymer comprising the plastic substrate to which the AgNWs are applied must also satisfy the mechanical requirements of the final device and withstand the device processing conditions. However, AgNW-based FTEs have some limitations, such as poor adhesion to coated plastic substrates, surface roughness, and difficulty in patterning. This study demonstrates a new strategy for creating AgNW-based patterned flexible poly(ethylene 2,6naphthalate) (PEN)-based electrodes with appreciable optical and electrical properties. Introducing poly(2-hydroxyethyl methacrylate) on the PEN substrate enhanced the adhesion between the substrate and AgNWs and improved the dispersibility of the AgNWs. Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) and a small amount of 2,4-hexadiyne-1,6-diol as a photosensitizer were coated onto the AgNW layer to improve the surface roughness and achieve an effective electrode pattern. By varying the AgNW concentration, we could tune the density and thickness of the AgNWs to optimize the sheet resistance and transmittance. Optimized AgNWs with a sheet resistance of 22.6 Ω/□ and transmittance of 92.3% at 550 nm were achieved. A polymer solar cell (PSC) was fabricated to evaluate the characteristics of the device employing the flexible electrodes. This PSC showed not only a high power conversion efficiency of 11.20%, similar to that of ITO-based devices, but also excellent mechanical stability, which is difficult to achieve in ITO-based flexible devices.

Engineered kirigami design of PVDF-Pt core–shell nanofiber network for flexible transparent electrode

“…, Table 1. Percolation exponents (n) and figures of merit (�) of the CS NF networks fabricated in this study and those of the nanostructured transparent conductors reported in previous studies 12,15,18,52,[54][55][56][57][58][59][60][61] . In comparison with those reported in earlier studies, the PVDF-Pt CS NF network prepared using the circular electrode collector exhibits an outstanding performance as a transparent conductor because of its large percolation figure of merit (� = 330.5) and small percolation exponent (n = 0.026).…”

Fabrication strategies for metallic nanowire flexible transparent electrodes with high uniformity

“…In comparison, the Ag NW FTEs on x-PVCn coated PET showed good homogeneity with a sheet resistance of 29.5 ± 7.2 Ω sq −1 . Kwon et al 123 prepared high-performance Ag NW FTEs on a surface treated PEN substrate using poly(2-hydroxyethyl methacrylate) (PHEMA) as an underlayer. The contact angle of PEN was reduced from 84.2° to 46.5° after the surface coating of PHEMA, showing much better hydrophilic property, as shown in Fig.…”

Stretchable conductors for stretchable field-effect transistors and functional circuits

“…321 In addition, surface modification of the substrate is also been considered to be one of the effective technology to improve the dispersion of NWs. 323 Introduction of poly(2-hydroxyethyl methacrylate) into the substrate enhances the adhesion between the substrate and AgNWs, improving the AgNW dispersibility. 323…”

“…323 Introduction of poly(2-hydroxyethyl methacrylate) into the substrate enhances the adhesion between the substrate and AgNWs, improving the AgNW dispersibility. 323…”