Bending response performance in nitrogen-doped reduced graphene oxide-PEDOT:PSS: The impact of nitrogen flow rate on the nitrogen doping configurations

Abstract

Mechanical bending sensors play a pivotal role in various applications, from wearable devices to healthcare monitoring systems. The integration of nitrogen-doped reduced graphene oxide (NrGO) materials has emerged as a versatile approach, offering a promising avenue for enhancing the performances of these sensors. Various nitrogen doping configurations within the materials matrix have been found to profoundly influence the sensor's bending response. In this work, we identified that pyrrolic-N doping configurations were more dominant at lower nitrogen flow rates of 10 and 20 sccm, with the percentages of 52.9 and 48.7 %, respectively. These configurations exhibited a stable pattern of resistance changes in response to bending, particularly when subjected to bending angles of 55° and 65°. Despite some inconsistencies in bending response at lower bending angles, the sensors demonstrated heightened sensitivity, registering at 0.34 kPa. In contrast, sensors predominantly characterized by pyridinic-N configurations at 40 sccm maintained a consistent level of sensitivity across different bending angles, demonstrating remarkable stability and structural robustness, even after enduring 10,000 cycles. These findings indicated that pyridinic-N configurations play a critical role in enhancing sensor performance, ensuring reliable measurements across various mechanical deformations.