Co3O4 /N-doped RGO nanocomposites derived from MOFs and their highly enhanced gas sensing performance

Co3O4/N-doped reduced graphene oxide (N-RGO) nanocomposite with mesoporous structure was fabricated by using metal organic frameworks (MOFs) as both template and precursor growing on RGO sheets. Porous Co3O4 cubes were assembled and grown on the surface of N-RGO layers, while N was doped into RGO to form N-RGO in situ synthesis route. The effect of RGO initial concentration on structure, component and gas-sensing properties of Co3O4/N-RGO nanocomposite was studied. The gas-sensing result demonstrated that the sensor based-on Co3O4/N-RGO-0.5 (the mass of RGO was 0.5 mg) nanocomposite possessed better gas-sensing performances to ethanol, such as higher response, faster response-recovery time and lower working temperature than that of other samples. The enhanced gas-sensing properties of sensor based-on Co3O4/N-RGO-0.5 nanocomposite to ethanol could be attributed to increasing of specific surface area, coupling effect between Co3O4 and nitrogen doped RGO as well as the existence of N-doping RGO which improved electron transferring of material in sensing process. Co3O4/N-RGO-0.5 nanocomposite has been proved to be a promising gas-sensing material for detecting ethanol at a low temperature.