ZnO/Al2O3/CeO2 composite with enhanced gas sensing performance

In this paper, two kinds of layered double hydroxides (LDHs), ZnAl LDH and Ce-doped ZnAl LDH, were introduced as precursors to prepare composite oxides for gas sensing studies. Compared with ZnO/Al2O3 based from ZnAl LDH, the ZnO/Al2O3/CeO2 composite oxide obtained from Ce-doped ZnAl LDH shows higher gas response to ethanol and shorter response/recovery time as well as remarkable selectivity. The structure, morphology and chemical composition of the gas sensing materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM) and element analysis studies. Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) were used to examine the microstructure and chemical state of the composite oxides sensing materials.