MOF-derived porous NiO/NiFe2O4 nanocubes for improving the acetone detection

Exploring sensing materials with superior catalytic properties is of paramount importance for acetone detection. In this work, NiO/NiFe2O4 nanocubes derived from Ni/Fe bimetal metal-organic frameworks (MOFs) precursors are synthesized by one-step impregnation method and subsequent annealing process. The microstructure and morphology of the synthesized samples are investigated by a series of characterization. The results indicate that uniform and porous NiO/NiFe2O4 nanocubes are formed. The gas sensing properties of NiO/NiFe2O4 composites are systematically evaluated. Benefitting from the synergistic effect of abundant sites, p-p junction and high surface area, the optimal sensors based on NiO/NiFe2O4 (Ni/Fe=1.5 at) exhibit the best sensing performance. The sensors show the highest response (19.9-100 pm acetone), short response/recovery times (2.4 s/19.6 s), low detection limit (200 ppb) and a good humidity tolerance ((S-35% (RH)-S-95% RH)/S-35% RH= 0.095) to acetone at 200 degrees C. The results offer us a promising alternative to develop an ideal platform for acetone detection.