Enhanced Humidity Sensing using Graphene Oxide and Reduced Graphene Oxide Synthesized via Modified Hummers' Method

This study presents a method for synthesizing graphene oxide (GO) and reduced graphene oxide (rGO) to evaluate their humidity sensing capabilities. GO was synthesized using a modified Hummers' method. GO reduced to rGO using L-ascorbic acid under mild reaction condition. The optical properties were assessed through UV-visible and Raman spectroscopy, while structural characteristics were evaluated using several techniques, including powder X-ray diffraction (pXRD), fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The intensity ratio of D- by G-band (ID/IG) was calculated and analyzed using Raman spectra. Additionally, we compared the performance of GO with rGO in terms of response and recovery times. The study found that rGO exhibited a response of 11-97%, with a response time of 15s and a recovery time of 28s, yielding a hysteresis of 0.20%. In contrast, GO demonstrated a response time of 18 s, a recovery time of 31 s, and a hysteresis of 0.30%.