High sensing properties of Ce-doped α-Fe2O3 nanotubes to acetone

Pristine and Ce-doped (3, 4, 5 at% Ce) α-Fe2O3 nanotubes were synthesized by electrospinning method. The morphologies and structures of these samples were characterized by scanning electron microscope (SEM) and X-ray powder diffraction (XRD). The gas sensing properties of the four samples were investigated. The results showed that the sensitivity of the 4 at% Ce-doped α-Fe2O3 nanotubes reached 21.5–50 ppm acetone at 240 °C, which was about 8.3 times larger than that of pure α-Fe2O3 nanotubes. Meantime, the response and recovery times were about 3 and 8 s, respectively. The sensitivity of the lowest detecting limit to 1 ppm acetone was about 3. Moreover, the sensor also possessed the good selectivity and long-term stability to acetone.