Printable Fabrication of a Fully Integrated and Self‐Powered Sensor System on Plastic Substrates

Abstract

Wearable and portable devices contribute to a rapidly growing emerging market for electronics and can find wide applications for wireless communications, multifunctional entertainments, personal healthcare monitoring, etc. [1][2][3][4][5] Typically, wearable devices with attractive attributes such as flexibility, long cruising time, and operation safety are highly desirable. [6][7][8][9][10][11] Recent advances in fields of power generation devices enable sustainable energy harvesting from the environment, such as solar energy, mechanical vibrations and frictions, biofluid and thermal energy from human body, and converted into electricity without external power sources, which introduces the concept of "self-powered" systems. [12][13][14][15][16][17] To realize continuous operation of the entire self-powered devices without interruption from surrounding conditions variation, such as insufficient solar illumination, fully integrated self-powered systems that consist of energy harvesting/conversion devices (e.g., solar cells, nanogenerators, biofuel cells), energy storage devices as intermediate energy storage units (e.g., rechargeable batteries, supercapacitors) and functional devices (e.g., sensors, transistors, biomedical implants) are highly desirable. [18] Planar supercapacitors with interdigitated electrodes constructed on single substrate emerged as one of the highly competitive energy storage devices to complement/replace batteries, offering merits of high power density, separator-free architectures for device miniaturization, and favorable operational safety without using flammable electrolytes. [19][20][21][22] Especially for integration with energy harvesting devices dealing with highly volatile energy input, particularly in wearable applications, supercapacitors possess an appealing capability to accommodate fast and high charging current fluctuation. [23][24][25][26] Although self-sufficient energy modules (e.g., photovoltaic-batteries, nanogenerator-supercapacitors) and selfpowered sensors (e.g., nanogenerator-sensors, battery-sensors) have been reported previously, [12,23,[26][27][28][29][30][31][32] to our best knowledge, demonstration of a fully integrated self-powered sensor system on flexible substrate implemented via additive printable strategy is rarely achieved, mainly due to the challenges on fabrication procedures compatibility and system integration of different device components.Wearable and portable devices with desirable flexibility, operational safety, and long cruising time, are in urgent demand for applications in wireless communications, multifunctional entertainments, personal healthcare monitoring, etc. Herein, a monolithically integrated self-powered smart sensor system with printed interconnects, printed gas sensor for ethanol and acetone detection, and printable supercapacitors and embedded solar cells as energy sources, is successfully demonstrated in a wearable wristband fashion by utilizing inkjet printing as a proof-of-concept. In such a "wearable wristband", the harvested so...

Bioinspired Artificial Sensory Nerve Based on Nafion Memristor

“…Bioinspired neuromorphic system for touch sensing is highly demanded in artificial intelligence industry such as electronic skin (e‐skin) and personal healthcare monitoring due to its fault tolerance and power efficiency for facing complex real‐world problems such as executing dangerous mission or movement control . There are three key components in a biological sensory nerve—the sensory receptor cells, the neural passages, and parts of the brain involved in sensory perception .…”

The Road Towards Planar Microbatteries and Micro‐Supercapacitors: From 2D to 3D Device Geometries

“…Importantly, the integrated MSCs in this as‐fabricated system can efficiently store electrical energy from solar cell, and thus readily drive the gas sensor, displaying a highly sensitive response for NH 3 and HCl. Fan and co‐workers demonstrated a printable and wearable self‐powered sensing system coupled with inkjet printable MSCs and SnO 2 sensor on a single piece of polyethylene terephthalate ( Figure a–c). MnO 2 based MSCs, SnO 2 microsensors, and integrated circuits were directly printed to construct the monolithic system through relevant printable inks, except for amorphous silicon solar cell and other supporting electronic parts, including light‐emitting diode light, voltage regulator, and switches.…”

“…c) Response and recovery curves of as‐printed microsensor toward ethanol at room temperature. Reproduced with permission . Copyright 2018, Wiley‐VCH.…”

Hierarchical Ordered Dual‐Mesoporous Polypyrrole/Graphene Nanosheets as Bi‐Functional Active Materials for High‐Performance Planar Integrated System of Micro‐Supercapacitor and Gas Sensor

“…[ 13–15 ] So far, most integrated systems are assembled with serial devices based on multiple mono‐functional materials. [ 7,9,16–18 ] For instance, a MSC‐gas sensor integrated system was reported, based on polyaniline‐wrapped carbon nanotube MSC as energy storage unit and graphene gas sensor as energy consumption device. [ 9 ] However, the complicated preparation of various mono‐functional active materials for single‐function energy‐related units, and poor compatibility of multiple energy modules involving complex connections, substantially increase the difficulty in the efficient construction of the integrated systems.…”