MOF-derived ZnFe2O4/(Fe-ZnO) nanocomposites with enhanced acetone sensing performance

To further improve the acetone sensing performance of MOF-derived ZnO nanoparticles, the doping of Fe into the ZnO lattice and the heterostructure formation with ZnFe2O4 nanoparticles were simultaneously achieved by a solution-based method via the hydrolyzation of Zn-based MOF-5 in Fe(NO3)3 aqueous solution. The obtained ZnFe2O4/(Fe-ZnO) nanocomposites (the mole ratio of Fe/Zn = 0, 0.05, 0.10, 0.15, 0.20, 0.25 and 0.30) were characterized and confirmed by XRD, TEM, SAED, Element mapping, SEM, XPS and BET. Compared with the pristine ZnO nanoparticles, better acetone sensing characteristics in terms of gas response, sensitivity, stability, reproducibility and selectivity were achieved by the ZnFe2O4/(Fe-ZnO) nanocomposites at lower prime working temperatures, among which the nanocomposites with Fe/Zn = 0.15 exhibited the best comprehensive performance due to its largest BET surface area, abundance of adsorption sites for oxygen and acetone molecules, as well as the high and wide potential barrier at the interfaces.