Humidity sensors based on graphene/SnOx/CF nanocomposites

Abstract

In this study, we investigated the nanocomposites composed of graphene, SnO_x and carbon fibers (CFs) for humidity sensing applications. The composites were obtained by an electrospinning method followed by addition of graphene. SnO_x/CFs uniformly dispersed into graphene nanosheets. SnO_x and graphene were proved to be promising sensing materials. The amorphous carbon fibers could supply more channels for transportation of protons or electrons. Therefore, the composites exhibited high humidity sensing performance. The resistance of the sensor increases two times with decreasing relative humidity from 55% to 30%. The sensitivity to humidity increased by almost 100% after adding graphene to SnO_x/CF nanocomposites. The response and recovery times were 8 s and 6 s at 30% RH, respectively. The results demonstrated that rational design of nanocomposites with graphene could be a favorable strategy to improve humidity sensing properties.