 A high performance gas sensor with excellent sensing response at room temperature is presented based on zinc oxide slash reduced graphing oxide, Xeno slash RGO composites, which are successfully fabricated by a facile hydrothermal method. The Xeno slash RGO sensor with 1.5 milliliters of the RGO exhibits highest sensing response in a wide range from 5 ppb to 10 ppm and O2 concentration, and its response arrives at 13.46 when exposed to 2 ppm and O2 at room temperature. Furthermore, Xeno slash RGO sensors show short response time, 2 ppm, 26s, and recovery time, 2 ppm, 164 s at room temperature. The proposed Xeno slash RGO sensors present high sensitivity, excellent reproducibility, and stability. DFT calculations show that the increased electrical conductivity under exposure of an O2 gas are attributed to the numerous reactive sites and carrier mobility of RGO, demonstrating the huge potential for applications in industrial and environmental monitoring. This article was authored by Ziwei Chen, Hao Jiguo, Fuxing Zhang, and others.