Metal-organic frameworks-derived hollow zinc oxide/cobalt oxide nanoheterostructure for highly sensitive acetone sensing

Abstract A high-performance acetone gas sensor based on metal-organic frameworks (MOFs)-derived ZnO/Co3O4 nano-heterostructure was prepared by a facile precipitation reaction method. The as-synthesized ZnO/Co3O4 nanocomposite was characterized by X-ray diffraction (XRD), thermo-gravimetric (TG), scanning electron microscopy (SEM), energy dispersive X-ray spectra (EDS), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS), confirming its successful preparation and reasonability. The acetone sensing properties of ZnO/Co3O4 hollow polyhedron sample was investigated at the optimum working temperature of 300 °C. The experimental results reveal that the ZnO/Co3O4 nanocomposite has a significantly enhancement in acetone sensing performance, which showed high response, good linearity, short response/recovery time, excellent repeatability and outstanding selectivity. These results render the ZnO/Co3O4 hollow polyhedron an efficient sensing material for constructing high-performance acetone sensor. The mechanism of the enhanced acetone sensing performance were attributed to unique hollow nanostructure, catalytic effect of Co3O4 and the p-n heterojunctions in the ZnO/Co3O4 nanocomposite.