Hydrothermal synthesis of 3D urchin-like α-Fe2O3 nanostructure for gas sensor

Urchin-like α-Fe2O3 nanostructures were obtained by a facile chemical solution route combined with subsequent calcination process. The images of field emission scanning electron microscopy and transmission electron microscopy indicated that these nanostructures were composed of one-dimensional nanorods with the diameter of about 40–50 nm and the length of about 800 nm. When tested as sensing materials for gas sensors, these α-Fe2O3 nanostructures exhibited high response, good response and recovery characteristics to ethanol at the operating temperature of 260 °C. The response time was about 2 s to 100 ppm ethanol.