Pressure Sensor Based on a Lumpily Pyramidal Vertical Graphene Film with a Broad Sensing Range and High Sensitivity

Abstract

Wearable sensors are vital for the development of electronic skins to improve health monitoring, robotic tactile sensing, and artificial intelligence. Active materials and the construction of microstructures in the sensitive layer are the dominating approaches to improve the performance of pressure sensors. However, it is still a challenge to simultaneously achieve a sensor with a high sensitivity and a wide detection range. In this work, using three-dimensional (3D) vertical graphene (VG) as an active material, in combination with micropyramid arrays and lumpy holders, the stress concentration effects are generated in nano-, micro-, and macroscales. Therefore, the lumpily pyramidal VG film-based pressure sensor (LPV sensor) achieves an ultrahigh sensitivity (131.36 kPa–1) and a wide response range (0.1–100 kPa). Finite element analysis demonstrates that the stress concentration effects are enhanced by the micropyramid arrays and lumpy structures in micro- and macroscales, respectively. Finally, the LPV pressure sensors are tested in practical applications, including wearable health monitoring and force feedback of robotic tactile sensing.

Sugar-plastic assisted fabrication of hollow PDMS wearable fabrics toward excellent sensory capabilities

“…Like a porous polymer, fiber or fabric-based sensors with their deformable dimensions would greatly improve their sensing performance based on piezoresistive mechanisms. 30–32 Additionally, microstructures such as pyramids, 33–36 hemispheres, 37–40 etc. , constructed on a flexible sensing substrate surface have been reported to contribute to their sensitivity.…”

“…Like a porous polymer, ber or fabric-based sensors with their deformable dimensions would greatly improve their sensing performance based on piezoresistive mechanisms. [30][31][32] Additionally, microstructures such as pyramids, [33][34][35][36] hemispheres, 37-40 etc., constructed on a exible sensing substrate surface have been reported to contribute to their sensitivity. Unlike hydrogels with so microstructures, stiff microstructures with a higher modulus than the matrix can not only maintain a stable form under pressure but also enable rapid and immediate transmission of sensing information to the matrix, resulting in a rapid response.…”

Wearable Pressure Sensor Using Porous Natural Polymer Hydrogel Elastomers with High Sensitivity over a Wide Sensing Range

“…To meet diverse demands in different human body movements monitoring applications, such as subtle joint-bending detection and heavy foot tapping monitoring, pressure sensors are desired to possess high sensitivity over a wide sensing range. Wearable pressure sensors have been developed based on several major sensing mechanisms, including piezoresistive [ 7 , 8 ], capacitive [ 9 ], and piezoelectric [ 10 ] mechanisms. Among these, piezoresistive pressure sensors based on applied pressure transduction in an electrical conductance of sensing materials have been widely studied due to their easy signal acquisition, simple process, and simple circuit integration [ 11 ].…”

Machine Intelligence Accelerated Design of Conductive MXene Aerogels with Programmable Properties

“…MXene nanosheets), [24][25][26][27][28][29][30] functional fillers (e.g., cellulose nanofibers (CNFs), silk nanofibrils, chitosan), 29,[31][32][33][34] polymeric binders (e.g., gelatin), 25,26 and crosslinking agents (e.g., glutaraldehyde (GA), metal ions). 30,[35][36][37] By adjusting the proportions of these building blocks, one can fine-tune the end properties of the conductive aerogels, such as electrical conductivities and compression resilience.…”