2010 Volume 51 Issue 6 Pages 1163-1167
We are so far involved in the development of complete decomposition of organic wastes as well as volatile organic compounds (VOCs) by the use of thermally activated holes in titanium oxide (TiO2) at high temperatures of about 350–500°C. In this study, we intend to replace TiO2 with α-Fe2O3 (red hematite) in order to lower the operation temperature and also to electrically characterize α-Fe2O3 on the basis of the temperature dependence of electrical conductivity and Seebeck potential. Powdered α-Fe2O3 is found to exhibit a higher electrical conductivity at 500°C by three orders of magnitude as compared with that of room temperature. In addition, the Seebeck potential is negative in the temperature range between room temperature and 380°C, indicating that the dominant charge carriers are mostly holes. Our α-Fe2O3-coated catalyst-system exhibits equivalent or even better characteristics than that of TiO2, although the specific surface of α-Fe2O3 (4.10 m2/g) is two orders of magnitude smaller than that of TiO2 (298 m2/g).