Hydrothermally synthesized Pd-loaded SnO2/partially reduced graphene oxide nanocomposite for effective detection of carbon monoxide at room temperature

Abstract

In this paper, palladium (Pd)-loaded tin dioxide (SnO2)/partially reduced graphene oxide (PRGO) nanocomposites with different proportions of Pd loading and PRGO nanosheets were synthesized by the facile hydrothermal method for carbon monoxide (CO) sensing applications. The crystal structure, morphology and composition of sensitive materials were characterized by means of X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM) and energy-dispersive X-ray spectrometer (EDX), respectively. Characterization data show that PRGO nanosheets act as a template for growth of small-sized SnO2 nanoparticles. The gas sensing properties of all sensors were investigated by exposing them to various concentrations of CO gas ranging from 50 to 1600ppm at 26°C. The synthesized 5%Pd-loaded SnO2/PRGO-1.5% sensor exhibited a very reproducible performance with fast response and recovery time (∼2min) at 26°C. The ability of detecting CO gas at room temperature could be attributed to the high specific surface area of PRGO nanosheets, good conductivity of PRGO and special interactions between PRGO nanosheets and Pd-loaded SnO2 nanoparticles.