Composite of ZnO spheres and functionalized SnO₂ nanofibers with an enhanced ethanol gas sensing properties

Many studies have proven that composite type sensor utilizing two or multiple oxide material could prove to be an effective way to enhance the gas sensing performance. We have fabricated successfully the composite of ZnO spheres and functionalized SnO₂ nanofibers as a novel sensing material. The structure and morphology of the samples were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and BET test. A systematic comparison study reveals an enhanced gas sensing performance for the sensor made of ZnO-SnO₂ composite toward ethanol over undecorated ZnO spheres, SnO₂ nanofibers. The enhanced gas sensing properties is attributed to the unique hierarchical and n-n heterojunction structures.