Synthesis of ZnO@Fe2O3 microflowers with enhanced performance in volatile organic compound detection

Metal-oxide semiconductor is widely applied in gas sensor for volatile organic compound detection. However, these sensors usually exhibit poor selectivity and inferior sensitivity. Here, ZnO@Fe 2 O 3 microflowers were synthesized using FeOOH microflowers as precursors via a simple solution reaction route, followed by heat treatment. The ZnO@Fe 2 O 3 microflowers were characterized using a series of techniques, and their sensing responses to volatile organic compounds (VOCs) were evaluated in comparison with those of pristine Fe 2 O 3 . The ZnO@Fe 2 O 3 microflower sensor exhibited better responses to several gases, especially acetone, with a response of 74.3 towards 100 ppm acetone, which is 2.85 times higher than that of the Fe 2 O 3 microflower sensor. The sensor also presented high selectivity, reproducibility, and stability in sensing different VOCs. The large specific surface area , heterostructure , favorable hierarchical flower-like nanostructure assembled by the nanosheets , and high porosity of the ZnO@Fe 2 O 3 microflowers contributed to its enhanced gas-sensing responses. Overall, this synthetic strategy for fabricating flower-like ZnO@Fe 2 O 3 nanostructures can be widely applied.