The Synthesis of the Pomegranate-Shaped α-Fe(2)O(3) Using an In Situ Corrosion Method of Scorodite and Its Gas-Sensitive Property

The release of hazardous gas increases with the development of industry. The research of gas-sensitive materials has attracted attention. Nanoscale iron oxide (α-Fe(2)O(3)) is one of the research hotspots of gas-sensitive materials because it is a cheap, non-toxic semiconductor material. In this study, pomegranate-shaped α-Fe(2)O(3) was synthesized using an in situ corrosion method of scorodite. Spherical-shaped α-Fe(2)O(3) nanoparticles were included in the octahedral shells. The forming process of the structure was analyzed by a variety of measurements. The shell was formed first through the deposition of Fe(OH)(3), which was produced by hydrolyzing scorodite. Then, the corrosion was continued and Fe(OH)(3) precipitation was produced below the shell. The particles aggregated and formed spheres. The pomegranate-shaped α-Fe(2)O(3) was formed when the scorodite was hydrolyzed completely. The gas-sensing properties of α-Fe(2)O(3) were investigated. The results showed that pomegranate-shaped α-Fe(2)O(3) was responsive to a variety of gases, especially xylene. The value of R(a)/R(g) was 67.29 at 340 °C when the concentration of xylene was 1000 ppm. This indicated the pomegranate-shaped α-Fe(2)O(3) has potential application as a xylene gas sensor.