Micropyramidal Flexible Ion Gel Sensor for Multianalyte Discrimination and Strain Compensation

Abstract

A highlysensitive and flexible gas sensor that can detect a widerange of chemicals is crucial for wearable applications. However,conventional single resistance-based flexible sensors face challengesin maintaining chemical sensitivity under mechanical stress and canbe affected by interfering gases. This study presents a versatileapproach for fabricating a micropyramidal flexible ion gel sensor,which accomplishes sub-ppm sensitivity (<80 ppb) at room temperatureand discrimination capability between various analytes, includingtoluene, isobutylene, ammonia, ethanol, and humidity. The discriminationaccuracy of our flexible sensor is as high as 95.86%, enhanced byusing machine learning-based algorithms. Moreover, its sensing capabilityremains stable with only a 2.09% change from the flat state to a 6.5mm bending radius, further amplifying its universal usage for wearablechemical sensing. Therefore, we envision that a micropyramidal flexibleion gel sensor platform assisted by machine learning-based algorithmswill provide a new strategy toward next-generation wearable sensingtechnology.