Fragmented Graphene Aerogel/Polydimethylsiloxane Sponges for Wearable Piezoresistive Pressure Sensors

Abstract

High-performance flexible pressure sensors are critical to realizing electronic skin and wearable devices. It is the persistent pursuit of researchers to develop more sensitive flexible pressure sensors. Here, we propose a simple and effective strategy to fabricate flexible piezoresistive pressure sensors based on fragmented graphene aerogel (FGA)/polydimethylsiloxane (PDMS) sponges. Using FGA as a conductive filler and NaCl particles as a porogen and blending with PDMS, a composite material FGA@PDMS with a sponge structure was obtained. Then, the composite FGA@PDMS was dip-coated with FGA to achieve the FGA/FGA@PDMS sponge. Finally, the interdigitated electrode was printed as the bottom electrode by the screen-printing process to complete the preparation of the FGA/FGA@PDMS sensor. The results show that the fabricated flexible piezoresistive pressure sensor has higher sensitivity (0–10 kPa, 2235.84 kPa–1), good recovery, shorter response time (∼120 ms), and stable response under 1000 cycles of loading and unloading. Moreover, we investigated the applicability of the FGA/FGA@PDMS sensor as a wearable device and its application in practical sensing. Human motion detection such as arm bending, fingers, and soles of the feet shows that the sensor has good detection ability. The light-emitting-diode series circuit and the bluetooth-based wireless pressure sensor verification prototype system demonstrate the potential of the sensor for practical applications.

Conductive Cross-Linkable PDMS-MXene Nanosheet Networks on Polyurethane Sponges as Robust Superhydrophobic Sensors for Human Motion Detection

“…Wearable piezoresistive sensors that transduce pressure into resistance signals in a real-time manner present great prospects in body movement monitoring, flexible electronic skins, human–machine interactive interfaces, and portable healthcare devices. − They have attracted extensive research interests for their complementary advantages with piezoelectric and capacitive sensors. − Conventionally, the piezoresistive sensors are fabricated with elastic polymers as flexible support [e.g., poly­(dimethylsiloxane) (PDMS), , polyurethane (PU), ethylene- co -vinyl acetate, thermoplastic elastomer, hydrogel, , etc.] as well as conductive nanomaterials as functional sensing elements (e.g., carbon nanotubes (CNTs), , graphene, MXene, Ag nanomaterials, etc.).…”

Lightweight, flexible, and conductive PEDOT:PSS coated polyimide nanofibrous aerogels for piezoresistive pressure sensor application

“…are widely employed in dipcoating processes for sponges to enhance their conductivity. [27][28][29][30] Typically, these conductive materials are generated through intricate and expensive procedures, posing challenges for creating a consistent and uniform ''ink'' suitable for dip coating; furthermore, resultant conductive sponges might encounter stability concerns, such as the potential detachment of coated carbon material or metal components onto the sponge due to inadequate adhesion between conductive substances and sponges.…”

High-sensitivity, ultrawide linear range, antibacterial textile pressure sensor based on chitosan/MXene hierarchical architecture

“… 14 Among these pressure sensors, piezoresistive pressure sensors have been widely adopted because of their simple device structure and easy signal processing. The practical applications of piezoresistive pressure sensors lie on their sensing performance especially high sensitivity over a wide linearity for easy signal processing, 15 which is mainly depending on the deformation behavior of elastomers (such as polydimethylsiloxane (PDMS), 16 polyurethane (PU), 17 , 18 polyimide (PI), 19 , 20 etc.) as well as active materials (such as metal wires, 21 MXene, 22 carbon nanotubes (CNT), 23 graphene, 24 etc.).…”