Multilayered Ag NP–PEDOT–Paper Composite Device for Human–Machine Interfacing

Abstract

Flexible pressure sensors have attracted increasing interest because of their potential applications on wearable sensing devices for human−machine interface connections, but challenges regarding material cost, fabrication robustness, signal transduction, sensitivity improvement, detection range, and operation convenience still need to be overcome. Herein, with a simple, low-cost, and scalable approach, a flexible and wearable pressure-sensing device fabricated by utilizing filter paper as the solid support, poly(3,4-ethylenedioxythiophene) to enhance conductivity, and silver nanoparticles to provide a rougher surface is introduced. Sandwiching and laminating composite material layers with two thermoplastic polypropylene films lead to robust integration of sensing devices, where assembling four layers of composite materials results in the best sensitivity toward applied pressure. This practical pressure-sensing device possessing properties such as high sensitivity of 0.119 kPa −1 , high durability of 2000 operation cycles, and an ultralow energy consumption level of 10 −5 W is a promising candidate for contriving point-of-care wearable electronic devices and applying it to human−machine interface connections.

Bioinspired, Self-Powered, and Highly Sensitive Electronic Skin for Sensing Static and Dynamic Pressures

“…The sensitivity (S) of the self-powered skin sensors can be defined as to dynamic pressures was also characterized as shown in Figure S9, indicating the similar sensitivity and linear sensing range as the static measurement. It should be noticed that the sensitivity of our self-powered skin sensor is greatly improved compared with previously reported piezoresistive pressure sensors, 11,[55][56][57][58] which may be attributed to the employment of the double side tape as the spacer when assembling the device. The employment of spacers between the composite films enables the reduction of conductive pathways when there is no external pressure loaded on the sensor device, which can minimize the static power consumption and boost up the pressure sensitivity simultaneously.…”

Designing Sensing Devices Using Porous Composite Materials

“…For example, mechanical sensors can also be constructed by utilizing different aspects of the porous material for other intriguing purposes. By integrating with conductive additives, e.g., conductive polymers [17,39], metal nanoparticles [17], or carbon nanotubes [21,40,41], soft porous materials can become electrically conductive. This material property modification enriches the usefulness of produced composites, where a sensing device functioning from a different aspect can now be designed.…”

“…Alternatively, cellulose-based paper material can also be used as the sensing device supporting substrate. A pressure sensor made by holding pieces of stacked conductive paper with lamination films was designed by Tsai et al [17]. Filter paper fibers were first coated with the conductive polymer PEDOT, and their surfaces were thereafter decorated with silver nanoparticles (AgNPs).…”

Transduction Mechanisms, Micro-Structuring Techniques, and Applications of Electronic Skin Pressure Sensors: A Review of Recent Advances

“…For all strategies, the resultant micro-structuring has a limited level of tailoring. Incorporation of sponges [ 192 , 193 , 194 , 195 , 196 , 197 , 198 , 199 ], foams [ 200 , 201 , 202 , 203 , 204 , 205 , 206 , 207 ], paper [ 208 , 209 , 210 , 211 , 212 ], and natural or synthetic fabrics (such as cotton, leather, silk, polyamide fabric, polyester fabric, polypropylene fabric, polyurethane fibers, and tissue paper) [ 32 , 123 , 134 , 213 , 214 , 215 , 216 , 217 , 218 , 219 , 220 , 221 , 222 , 223 ] that are afterwards chemically modified to become conductive, typically by carbonization [ 123 , 196 , 216 ] or by dip-coating with rGO [ 192 , 195 , 219 , 221 ], graphene [ 134 , 223 ], CNTs of different types [ 209 , <...>…”