Kirigami‐Inspired Stretchable Conjugated Electronics

Abstract

The conducting nature of π-conjugated polymers enables the strain-dependent electronic and capacitance sensor. Its light-emitting nature facilitates its optical strain sensing due to the emission change under strain, which is unaccessible in the conductor and insulator materials. The semiconducting materials used to form stretchable components are typically achieved by transferring the films onto the soft stretchable substrate. Random polymer chain distribution with defects would exist, and a significant amount of cracks could occur during the transferring process. The geometric engineering has been applied to simultaneously achieve high stretchability and conductivity of conjugated polymers. [20-22] In this context, the kirigami, which refers to cutting materials into certain patterns to acquire desirable structures, has inspired the programmable stretchable electronics. [23,24] The kirigami structures reveal excellent potential to achieve the desired stretchable electronic properties. Here, we report a liquid/air assembly to grow large-area freestanding poly2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene (MEH-PPV) nanosheets, while their unique electronic and light-emitting properties arise from the electron coupling strength between π-stacking units and further high degree of molecular packing arrangements. The freestanding MEH-PPV nanosheets at the water-air interface ensure the conformal contact onto various surfaces. These contribute to the development of conformal sensors based on the sensitivity of band gap to π-π stacking. Furthermore, the geometric engineering with kirigami structures on the freestanding MEH-PPV films not only extends its stretchability but also sustains its conductive and light-emitting properties, which significantly enhance its stretchable applications.

Emergence of Ferroelectricity in Halide Perovskites

“…Owing to their unique properties, 2D lead iodide perovskite ferroelectrics are expected to be utilized in high-performance applications in future. [74] Vertical PFM phase image. c) Room temperature vertical PFM phase signal versus the tip voltage bias at a selected point.…”

All-Printed Paper-Based Micro-supercapacitors Using Water-Based Additive-Free Oxidized Single-Walled Carbon Nanotube Pastes

“…Paper is an intimate and ubiquitous material in our daily activities. In recent years, paper has been considered to be cheap; thus, it is a promising substrate for flexible electronics. , Paper-based flexible devices are gaining increasing attention as cost-effective, eco-friendly, lightweight, and disposable electronics for wearable applications. − For decades, there have been many studies on the integration of electronic components, such as interconnections, transistors, diodes, inductors, memories, sensors, and energy harvesting/storage devices into paper substrates. − Moreover, origami- and kirigami-inspired device structuring can allow the fabrication of ultra-stretchable paper-based electronics exhibiting a stretchability of over 1000%. − …”

3D Electrodes for Bioelectronics

“…The second method is kirigami, which refers to cutting, folding, and attaching materials into certain patterns to acquire 3D structures from a planar sheet or film. [186][187][188][189] The remarkable characteristics of kirigami is that rigid materials can become stretchable as compared to other elastomer-based stretchable materials. [187] Figure 10b,c shows two examples of microscale kirigami patterns in nanocomposites after photolithography.…”