Acetone sensing performance of ZnFe₂O₄/ZnO/g-C₃N₄ composites: morphology, structure and charge transfer

In this study, a novel acetone detection strategy is developed by utilizing graphitic carbon nitride (g-C₃N₄) nanosheets combined with ZnFe₂O₄/ZnO yolk–shell microspheres (ZnFe₂O₄/ZnO YSM), prepared through template-free solvothermal synthesis. The gas sensing performance of the ZnFe₂O₄/ZnO/g-C₃N₄ composites was systematically evaluated by comparing them to ZnFe₂O₄/ZnO YSM. Especially, the sensor based on 20 wt% g-C₃N₄ of ZnFe₂O₄/ZnO/g-C₃N₄ exhibited superior sensing properties to 500 ppm acetone at 300 °C, as well as excellent response-recovery characterizes (8 s/79 s) and long-term stability over 45 days. The improved acetone sensing mechanism may be attributed to the unique yolk-shell microsphere structure and extended charge transfer within the n-n heterojunction of ZnFe₂O₄/ZnO/g-C₃N₄. This work provides a novel approach of developing acetone sensors with rapid detection capabilities and low power consumption.