Pressure‐Temperature Dual‐Parameter Flexible Sensors Based on Conformal Printing of Conducting Polymer PEDOT:PSS on Microstructured Substrate

Abstract

Flexible sensors play an important role in collecting stimuli information and sending them to a central processing unit or cloud for analysis and decision‐making. As much information is needed to be collected, the fabrication of multiparameter flexible sensors is becoming increasingly urgent. To this end, conducting polymer‐based composites have been proven as promising materials for developing pressure‐temperature dual‐parameter sensors. However, fabrication of ideal dual‐parameter sensors with fully decoupled pressure‐temperature readings, good sensitivity, and a simple preparation process remain challenges. Here, a strategy of fabricating a pressure‐temperature dual‐parameter sensor based on conformal printing of conducting polymer poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) on the surface of microstructured polydimethylsiloxane (PDMS) substrate is demonstrated. It is found that secondary doped PEDOT:PSS provides temperature‐independent conductivity. Combined with the sea‐island microstructured PDMS substrate, a screen‐printed flexible sensor demonstrates fully decoupled pressure‐temperature reading ability, competitive sensitivity, and good stability. The excellent sensing properties of the devices, with a maximum pressure sensitivity of 134.25 kPa−1 and linear response region over 300 kPa as well as highly sensitive temperature sensing for finger touch, together with their unique advantages of low‐cost and large‐area fabrication, make the printed flexible dual‐parameter sensors promising applications in electric‐skin (e‐skin), human‐machine interaction, and robotics.

Multi-Level Pyramidal Microstructure-Based Pressure Sensors with High Sensitivity and Wide Linear Range for Healthcare Monitoring

“…The detection range and sensitivity are usually two important sensing characteristics determined by the compressibility of the microstructures in the flexible pressure sensors . In general, the large detection range usually is obtained at the expense of the sensitivity. , Here, in order to widen the detection range with the improved sensitivity, the multi-level pyramidal microstructures with rich contact areas and good stress distribution are designed and fabricated by controlling the diameter and height of pyramidal microstructures through microsphere self-assembly, reactive ion etching (RIE), magnetron sputtering, and wet etching processes, as shown in Figure a.…”

Flexible resistive tactile pressure sensors

“…On the manufacturing side, in addition to being synthetic, the highly conductive, chemically stable, and translucent PEDOT:PSS is also machine-printable, which greatly contributes to sensor material savings and cost reductions. 125,126 In response to the current resource scarcity, researchers have been exploring new types of conductive polymer materials for sensor fabrication. Yin et al investigated the use of "green" renewable resource cellulose nanobers (CNF) to create multifunctional exible sensors.…”

A skin-friendly soft strain sensor with direct skin adhesion enabled by using a non-toxic surfactant

“…6,11,12 Particularly, the poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS), a conductive polymer, was widely used for preparing the composite with water-soluble polymers, such as polyvinyl alcohol (PVA) and waterborne-polyurethane (WPU), due to the high miscibility of those materials. 12–14 Despite the simplicity of those approaches, the water-soluble composite involves severe issues of vulnerable nature to the environment, especially moisture. Therefore, environmentally stable materials, such as polydimethylsiloxane (PDMS), polystyrene- block -poly(ethylene-ran-butylene)- block -polystyrene (SEBS), and Ecoflex, could be promising candidates for creating composites with PEDOT:PSS to develop dry-adhesive soft electronic materials.…”

“…of those materials. [12][13][14] Despite the simplicity of those approaches, the water-soluble composite involves severe issues of vulnerable nature to the environment, especially moisture. Therefore, environmentally stable materials, such as polydimethylsiloxane (PDMS), polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene (SEBS), and Ecoflex, could be promising candidates for creating composites with PED-OT:PSS to develop dry-adhesive soft electronic materials.…”