Self-Powered, Self-Healed, and Shape-Adaptive Ultraviolet Photodetectors

Abstract

The emergence of self-healing devices in recent years has drawn a great amount of attention in both academics and industry. Self-healed devices can autonomically restore a rupture as unexpected destruction occurs, which can efficiently prolong the life span of the devices; hence, they have an enhanced durability and decreased replacement cost. As a result, integration of wearable devices with self-healed electronics has become an indispensable issue in smart wearable devices. In this study, we present the first self-powered, self-healed, and wearable ultraviolet (UV) photodetector based on the integration of agarose/poly­(vinyl alcohol) (PVA) double network (DN) hydrogels, which have the advantages of good mechanical strength, self-healing ability, and tolerability of multiple types of damage. With the integration of a DN hydrogel substrate, the photodetector enables 90% of the initial efficiency to be restored after five healing cycles, and each rapid healing time is suppressed to only 10 s. The proposed device has several merits, including having an all spray coating, self-sustainability, biocompatibility, good sensitivity, mechanical flexibility, and an outstanding healing ability, which are all essential to build smart electronic systems. The unprecedented self-healed photodetector expands the future scope of electronic skin design, and it also offers a new platform for the development of next-generation wearable electronics.

Self‐Healing Soft Sensors: From Material Design to Implementation

“…The field has expanded to cover additional physical signals that can be generally categorized as electromagnetic signals. Self‐healing physical sensors for UV, [ 87 ] NIR, [ 57 ] proximity, [ 88 ] and magnetic fields [ 57 ] have been reported. Multiple methods were used to obtain these sensing capabilities, including current photogeneration, magnetothermal, and photothermal conversion.…”

“…In another demonstration using an active layer made of a heterojunction of PEDOT:PSS and a zinc oxide (ZnO) nanocomposite, a self‐powered, self‐healing, and wearable UV photodetector was constructed. [ 87 ] Upon illumination, the photogenerated current was used to measure the power of UV illumination. The device was seen as a complementary component of e‐skin and wearable devices for measuring UV exposure.…”

“…Reproduced with permission. [ 87 ] Copyright 2020, American Chemical Society. d) Thermoelectric‐based self‐healing sensors.…”

“…In another demonstration, an energy harvesting and self‐healing photogenerator‐based sensor was described (Figure 8c). [ 87 ] UV light, the targeted signal, led to the generation of a measurable current. The UV photodetector was based on a heterojunction of PEDOT:PSS and ZnO.…”

Two‐Dimensional Material‐Enhanced Flexible and Self‐Healable Photodetector for Large‐Area Photodetection

“…[ 1–6 ] Among them, wearable/flexible photodetector is regarded as an essential component to develop the next‐generation flexible optoelectronic devices and systems, [ 7–13 ] especially in the fields of non‐invasive health and environmental monitoring, [ 1–3,6 ] artificial skin, [ 14–16 ] image sensing, [ 17 ] flexible displays, [ 18–21 ] consumer electronics, [ 22–25 ] and optical communication. [ 7,26,27 ] Besides excellent photoresponse, ideal wearable photodetectors are also required to possess good flexibility, [ 7,8,10,28–30 ] stretchability, [ 24,31–33 ] and stable photoresponse in harsh environment, [ 4,34–36 ] such as large mechanical deformation and damage. [ 36–38 ] Furthermore, personalized design of wearable optoelectronic devices with adjustable feature sizes and performances are much appreciated, [ 39,40 ] to accommodate different user applications and circumstances.…”