Comparison of printing techniques for textile PEDOT electrodes: electrical characterization under operating conditions

The advances in material science and nanotechnology have led 3D printing to be the most versatile method for custom sensor fabrication. 3D printing is nowadays a rather common technique for production of custom objects for both scientific research and personal hobbies, making use of plastic filaments for structural printing. New and improved 3D printers allow the use of special made inks for specific analytes sensing, opening the way for countless applications in sensor manufacture. This thesis studies the 3D printing of the PEDOT:PSS polymer as a base for textile applications. Poly(3,4-ethylenedioxythiophene) doped with poly(styrene sulfonate) (PEDOT:PSS) is a semiconducting polymer that is flexible and compatible with many textile materials, being already widely used in organic optoelectronic devices. PEDOT:PSS is able to be mixed with other reagents to create conductive ink that can be deposited and dried onto textile material, useful for different textile sensing applications. Two different inks were fabricated, analyzing their electrical and morphological properties when 3D printed onto two different, commercially available, gauze fabrics. One of the fields in sensing with the most potential for wearable sensors applications is the monitoring of wounds. The healing process of an external injury is extremely vulnerable to foreign interference, such as proper sterilization of the wound and continuous change of the wound’s dressing: monitoring a wound’s status through sensors printed onto the gauze fabric may completely remove external influences, leading to a faster recovery. The ”Results” chapter contains the morphological and electrical properties of the two inks when 3D printed on either fabric. The inks were also analyzed in a wet environment, simulating that of a wound’s.