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

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.