Optimization of PEDOT:PSS Aqueous Solution for High-Performance Flexible Temperature Sensors

Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate ) (PEDOT:PSS) has great potential in high-performance flexible temperature sensors for healthcare, environmental monitoring, intelligent robots, and so on. However, it is rare to study the influence of synthesis parameters of PEDOT:PSS aqueous solution on the performance of temperature sensors. In this work, we synthesized PEDOT:PSS aqueous solutions via chemical oxidative polymerization and employed them to make flexible temperature sensors. By optimizing the synthesis parameters, including 3,4-ethylenedioxythiophene (EDOT) concentration, PSS:EDOT mass ratio, Na2S2O8:EDOT mass ratio, polymerization time, and substrate type, the high-performance flexible temperature sensor was successfully fabricated. The sensor exhibits an impressive sensitivity of -1.36 %/° and an excellent linearity of 0.993 in the temperature range of 28 ° to 60 °. Moreover, the sensor also possesses a high temperature resolution of 0.2 °, fast response and recovery time of 4.2 s and 7.0 s, and excellent flexibility. The optimized PEDOT:PSS aqueous solution can be used to fabricate high-performance flexible sensors.