Nanostructured Ce/CeO2-rGO: Highly Sensitive and Selective Electrochemical Hydrogen Sulphide Sensor

Abstract

AbstractHerein, cerium/ceriumoxide nanoparticles have been decorated on reduced graphene oxide (Ce/CeO2-rGO) for room temperature electrochemical determination of H2S in 0.5 M KOH electrolyte. There is a superior linear correlation between the peak current density and H2S content in the tested range of 1–5 ppm. Moreover, compare to other abundant gases shows no response such as CO2at the potentials of H2S sensing, confirms no interfere with H2S detection. And it reveals that the Ce/CeO2-rGO nanocomposites is highly selective and sensitive system for the detection of H2S gas sensing. Ce/CeO2-rGO synthesized by simple chemical approach and further characterized by X-ray diffraction (XRD), Furrier transform infra-red (FTIR), Field emission-scanning electron microscopy (FE-SEM) coupled energy dispersive analysis of X-ray (EDAX) and BET-surface area measurements confirms the porosity of synthesized nanomaterial and homogeneous decoration of Ce/CeO2nanoparticles on rGO sheets. The electrochemical studies i.e. linear sweep voltammetry (LSV) of Ce/CeO2-rGO demonstrates the electrochemical H2S gas sensing at room temperature with lower gas concentration i.e 1 ppm detection at low concentration. Furthermore, the applcablity of sensor the analytical parametrtrs like LOD and LOQ has been calculated and were found to be 0.92 and 9.22 µM respectively. The sensing mechanism is believed tobe based on the modulation of the current and applied potential path across the electron exchange between the cerium oxide and rGO sites when exposed to H2S.