Flexible Sensors Based on Electrohydrodynamic Jet Printing

Flexible sensors have potential applications in the fields of soft robotic , wearable electronics and biomedical, etc. , due to their stable sensing performance under large deformation conditions , such as ,bending , twisting , and stretching. Compared with traditional photolithography technology for constructing flexible sensors , printing as one of additive manufacturing technologies has the advantages of green, low-cost and large-area manufacturing. In various printing technologies, electrohydrodynamic jet (e-jet) printing technology enable replace traditional lithography technology to fabricate high-resolution flexible sensors , because its compatibility with multiple functional materials and special working mechanism. Recently , e-jet printing technology shows wide application prospects in the fields of miniaturized flexible sensors, such as flexible pressure sensors, flexible gas sensors and flexible electrochemical sensors. In the review , we focused on the recent developments of materials, processes and applications of e-jet printing technology in the field of flexible sensor. Firstly, we introduced the working principle of e-jet printing technology and various e-jet printing ink materials in detail. Then, the interface controlling methods between ink and flexible substrate in e-jet printing progress were discussed. Subsequently, the applications of e-jet printing technology for flexible pressure sensors, flexible gas sensors and flexible electrochemical sensors were provided. Finally , we presented the future challenges and opportunities of next-generation e-jet printing in high resolution flexible sensors.