Roll-to-Roll Encapsulation of Metal Nanowires between Graphene and Plastic Substrate for High-Performance Flexible Transparent Electrodes

Abstract

Transparent conductive film on plastic substrate is a critical component in low-cost, flexible, and lightweight optoelectronics. Industrial-scale manufacturing of high-performance transparent conductive flexible plastic is needed to enable wide-ranging applications. Here, we demonstrate a continuous roll-to-roll (R2R) production of transparent conductive flexible plastic based on a metal nanowire network fully encapsulated between graphene monolayer and plastic substrate. Large-area graphene film grown on Cu foil via a R2R chemical vapor deposition process was hot-laminated onto nanowires precoated EVA/PET film, followed by a R2R electrochemical delamination that preserves the Cu foil for reuse. The encapsulated structure minimized the resistance of both wire-to-wire junctions and graphene grain boundaries and strengthened adhesion of nanowires and graphene to plastic substrate, resulting in superior optoelectronic properties (sheet resistance of ∼8 Ω sq(-1) at 94% transmittance), remarkable corrosion resistance, and excellent mechanical flexibility. With these advantages, long-cycle life flexible electrochromic devices are demonstrated, showing up to 10000 cycles.

The Way towards Ultrafast Growth of Single‐Crystal Graphene on Copper

“…The growth of large‐area high‐quality graphene films is fundamental for the upcoming graphene applications. Chemical vapour deposition (CVD) method offers good prospects to produce large‐size graphene films due to its simplicity, controllability and cost‐efficiency 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75. Many researches have verified that graphene can be catalytically grown on metallic substrates, like ruthenium (Ru),13, 14 iridium (Ir),15, 16 platinum (Pt),17, 18, …”

Copercolating Networks: An Approach for Realizing High-Performance Transparent Conductors using Multicomponent Nanostructured Networks

“…Recently, a number of applications of hybrid AgNW-graphene have been demonstrated in the literature ranging from its use as electrodes in light-emitting diodes to atomically thin barrier layer for protection against high-energy radiation [21,29,30,[52][53][54][55][56][57][58][59][60][61]. The schematic shown in Figure 6 summarizes the recent progress in the field and Table 2 presents their key physical properties.…”

“…Recently, Deng et al [29] and Chandrashekhar et al [30] have reported RTR manufacturing of hybrid silver nanowiregraphene films with exceptionally good properties. These efforts have not only provided the prototype laboratory based multifunctional applications of hybrid copercolating TCE, but could also enable mass production of related components.…”

“…Although Ag-nanowire networks are widely used for demonstration of TCO-alternative technologies, the rapid oxidation of Ag is a key concern [29]. Indeed, the resistance degrades rapidly even after relatively short exposure to environment and long-term stability is also poor.…”

“…Indeed, the resistance degrades rapidly even after relatively short exposure to environment and long-term stability is also poor. Indeed, the corrosion resistance of Cu-NT nanonets is not significantly better [29]. Nanonets based on other materials (e.g., Au, Pd) are expected to be more stable, however, stability data are often not available.…”