Room temperature humidity sensors based on rGO/MoS2 hybrid composites synthesized by hydrothermal method

Recently, two-dimensional (2D) materials have attracted attention for gas sensor fields due to their unique properties such as high surface to volume ratio and numerous active sites. In particular, reduced graphene oxide (rGO) and MoS2 are one of the most promising materials for humidity sensor due to the oxygen containing functional groups on the surface of rGO and dangling bonds at the edge site of MoS2. Herein, we present 2D rGO/2D MoS2 hybrid composites (MS-GOs) synthesized by hydrothermal method. rGO and MoS2 are mixed with different molar ratios and drop-casted on SiO2 substrate with Pt interdigitated electrode. At an optimized molar ratio of rGO/MoS2, the sensor device exhibits high sensitivity, good selectivity, rapid response and recovery, and good linearity for humidity sensing. The enhanced sensing properties are attributed to the p-n junction between rGO and MoS2. Our work provides an efficient way for realizing high-performance and fast responding humidity sensors utilizing 2D-2D heterojunction materials based chemoresistive humidity sensors for use in diverse applications.