Evaluation Humidity Sensing Properties of Graphene/HS-TiO₂ Nanocomposites

This paper reports on a nanocomposite synthesized by sol-gel procedure comprising graphene sheets with hollow spheres of titanium dioxide (G/HS-TiO₂) with varying weight percentages of graphene for the purpose of humidity sensors. The surface morphology of the nanocomposite was characterized using transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDX). The structural properties were examined using X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR). The response to 12-80% RH at room temperature exhibited sensitivity (S = 135). However, the relative humidity range of 12-90% at room temperature exhibited higher sensitivity (S = 557). Sensors fabricated using the proposed nanocomposite exhibited high sensitivity to humidity, high stability, rapid response times, and rapid recovery times with hysteresis error of less than 1.79%. These results demonstrate the outstanding potential of his material for the monitoring of atmospheric humidity. This study also sought to elucidate the mechanisms underlying humidity sensing performance.