Silver Nanotube Networks with Ultrahigh Strain Limit as Reliable Flexible Transparent Electrode and Tactile Sensor

Abstract

Durable and extremely deformable electrodes play a significant role in the field of high‐strain flexible electronics, including wearable electronics and flexible tactile sensor. However, the existing flexible transparent electrodes hardly have a high strain limit and low square resistance simultaneously, like the combination of carbon‐based electrodes and metal electrodes. Herein, a semicovered silver nanotube (SC‐AgNT) network electrode is proposed. The SC‐AgNT network electrode consists of semicovered polymer nanofibers and a highly integrated Ag nanotube network for achieving high strain limit and low square resistance. Further, a tactile sensor based on this electrode is built, demonstrating the advance of the new electrodes. The strength enhancement layer consists of polyvinyl alcohol (PVA) nanofibers in the SC‐AgNT network electrode, making the electrode have the minimum bending radius of 0.1 mm and the maximum twist angle of 120° (0.9 Ω sq−1 at 94% transmittance). A tactile sensing interface based on the SC‐AgNT network electrode displays highly stable electrical properties under multiple types and times of comprehensive deformation and touch deformation. The technical strategy for strengthening metal network electrodes and preparing integrated low‐resistance metal networks can be extended to enhance the performance of other metal‐based flexible electrodes and flexible devices.

Recent advances in nanofiber-based flexible transparent electrodes

“…The strain sensor can respond in 0.15 s. Even a tiny strain of 0.1% can be detected, enabling the collection of subtle physiological signals. In addition, some studies have also achieved high strain limit (a maximum twist angle of 120 • and a minimum bending radius of 0.1 mm) and low sheet resistance (0.9 Ω sheet resistance with 84% light transmittance) for tactile sensors fabricated by depositing a silver layer on the surface of polyvinyl alcohol NFs [208]. This further confirms the feasibility of this scheme.…”

Metallic Micro‐Nano Network‐Based Soft Transparent Electrodes: Materials, Processes, and Applications

“…[ 97 , 177 , 208 ] The detection of human movements for human healthcare monitoring is another common use of tactile sensors. In this instance, the new triboelectric sensors [ 198 , 206 ] are used in addition to resistive [ 9 , 188 , 263 ] and capacitive [ 264 ] ones.…”

A flexible metal nano-mesh strain sensor with the characteristic of spontaneous functional recovery after fracture damage

“…Various types of flexible strain sensors have been developed, including resistive sensors, 12,13 capacitive sensors, 14 friction sensors, 15 and piezoelectric sensors. 16 Among them, flexible resistive strain sensors are particularly desirable because of their simple structure and high sensing performance.…”