A Flexible Piezocapacitive Pressure Sensor with Microsphere-Array Electrodes

Abstract

Flexible pressure sensors that emulate the sensation and characteristics of natural skins are of great importance in wearable medical devices, intelligent robots, and human–machine interfaces. The microstructure of the pressure-sensitive layer plays a significant role in the sensor’s overall performance. However, microstructures usually require complex and costly processes such as photolithography or chemical etching for fabrication. This paper proposes a novel approach that combines self-assembled technology to prepare a high-performance flexible capacitive pressure sensor with a microsphere-array gold electrode and a nanofiber nonwoven dielectric material. When subjected to pressure, the microsphere structures of the gold electrode deform via compressing the medium layer, leading to a significant increase in the relative area between the electrodes and a corresponding change in the thickness of the medium layer, as simulated in COMSOL simulations and experiments, which presents high sensitivity (1.807 kPa−1). The developed sensor demonstrates excellent performance in detecting signals such as slight object deformations and human finger bending.

Flexible and Stretchable Pressure Sensors: From Basic Principles to State-of-the-Art Applications

“…Flexible and stretchable pressure sensors employing capacitive sensing typically consist of two conductive layers separated by a dielectric layer. The conductive layers can be made of metals [ 24 ] or conductive polymers [ 25 ] while the dielectric layer is often an elastomeric material with a high dielectric constant [ 26 ]. When pressure is applied to the sensor, the deformation of the elastomeric layer leads to a change in the separation distance between the conductive layers, thereby altering the capacitance.…”

Flexible highly conductive melamine foam/copper sulfide has both electrical heating and pressure sensing properties

“…1 Among them, the flexible pressure sensor can collect the signals of human physiological parameters in real-time according to different needs, and plays a complementary role in monitoring human activities and health status; [2][3][4][5] Portable heating wearable products can improve wearing comfort. 6,7 Flexible sensors can be divided into three types: piezoresistive, 8 piezoelectric, 9 and capacitive. 10 The piezoresistive sensors can convert mechanical deformation into resistance change.…”

Editorial for the Special Issue “Amorphous and Nanocrystalline Semiconductors: Selected Papers from ICANS 29”

“…This includes topics such as Si-based, oxide, perovskite, 2D thin films and nanostructures, device applications for TFTs, solar cells, and LEDs, as well as memory devices and emerging flexible electronics and neuromorphic applications. For example, new fabrication technologies of amorphous and nanocrystalline thin films, electronic and optical characteristics, and device applications are presented and discussed in [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 ], including theoretical work in an ab initio study [ 9 ], controllable growth and formation of Si nanowires [ 1 ], nanocrystals [ 2 ], and quantum dots [ 3 , 4 ]. There are also several papers that cover emerging memory devices.…”

“…There are also several papers that cover emerging memory devices. These include phase change memory [ 5 , 6 , 7 , 8 , 9 ] based on amorphous chalcogenide thin films and memristors based on transition metal oxides acting as an artificial synapse [ 10 , 11 , 12 ]; the improvement of electro-luminescence (EL) efficiency Er-doped oxide thin films [ 13 , 14 , 15 ]; 2D semiconductor thin films and perovskite for solar cells and aqueous Zn-air battery [ 16 , 17 , 18 , 19 ]; and flexible electronic materials for integrated strain sensors [ 20 , 21 ]. We anticipate that this Special Issue should interest a broad audience in these related fields.…”

“…Finally, this Special Issue features a study of the flexible electronic materials for sensor device applications. Shi and Pan’s group [ 20 , 21 ] presented a scalable porous piezoresistive/capacitive dual-mode sensor with a porous structure in polydimethylsiloxane (PDMS) and with multi-walled carbon nanotubes (MLCNTs) embedded on its internal surface to form a 3D spherical-shell-structured conductive flexible network. This kind of polymer flexible sensor can be assembled into a wearable sensor that has a good ability to detect human motion and can be used for simple gesture and sign language recognition.…”