Enhanced n-butanol sensitivity and selectivity of Sb-doped ZnO-Co3O4 nanoparticles synthesized by solvothermal method

Sb-doped ZnO-Co3O4 nanoparticles with excellent gas-sensing performance for n-butanol were synthesized by a simple one-step solvothermal route and annealing process. Microstructure, morphology, and element valence states were characterized by X-ray diffraction, field scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. Sensing performance of Sb-doped ZnO-Co3O4 composite nanoparticles for various volatile organic components was comprehensively investigated. Results show that nanocomposites exhibit high selectivity and sensitivity to n-butanol when doped with Sb at a level of 8%. Specifically, the selectivity of 8% Sb-doped ZnO-Co3O4 sensor to 100 ppm n-butanol reached a response of 61.129 at optimal operating temperature of 200 degrees C, which is significantly higher than that of ZnO-Co3O4 composite materials prepared without Sb doping. Improved sensing performance of Sb-doped ZnO-Co3O4 was attributed to electronic and chemical sensitization effects of Sb as well as the formation of shallow donor complex defects.