Photo-thermal converting polyaniline/ionic liquid inks for screen printing highly-sensitive flexible uncontacted thermal sensors

Flexible sensors are important candidates for future artificial intelligent devices and wearable electronics. Among the methods for the production of flexible sensors, printing has attracted increasingly more attention due to its precision and good reproducibility. In this work, conductive thermo-responsive inks were prepared by the combination of photo-thermal converting eigenstate polyaniline (PANI) and conductive ionic liquids (ILs) in response to temperature. These PANI/ILs inks can be easily screen printed onto various flexible substrates such as A4 paper, fabrics, and plastics to prepare flexible thermal sensors. Under a near infrared (NIR) irradiation such as an 808 nm light source without contact, the PANI absorbed the NIR irradiation and the temperature of the sensor chip was elevated. As a result, the ILs exhibited changes in conductivity and realized the thermo-sensitivity of the PANI/ILs-based chip. These low-cost, easy-to-handle conductive thermo-responsive PANI/ILs inks are good candidates for the preparation and production of flexible thermal sensors.

Automated summary

Conductive thermo-responsive inks were prepared by combining photo-thermal converting polyaniline and conductive ionic liquids. These inks can be used to print flexible thermal sensors which exhibit thermal sensitivity under near infrared irradiation, showing changes in conductivity. This low-cost and easy-to-handle solution is a promising candidate for flexible sensor production.