Growth and properties of single-crystalline gamma-Fe2O3 nanowires
JOURNAL OF PHYSICAL CHEMISTRY C 卷: 111 期: 13 页: 5034-5038 出版年: APR 5 2007，-0001，（）：
By carefully controlling the reacting conditions, including atmosphere, temperature, and time, we directly acquire the nanowires of ç-Fe2O3 from the nanowires of R-Fe2O3 in a reduced atmosphere. X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectrum, and transmission electronic microscope analyses demonstrate that the nanowires are single-crystalline ç-Fe2O3. The nanowires have a diameter ranging from 50 to 90 nm and their typical lengths are in the range of 1020 ím. The optical property of the nanowires is observed by photoluminescence spectrum. The magnetic behavior of it is investigated by a magnetic property measurement system. The blocking temperature is found to be about 200 K. In addition, the mechanism of the transformation from R-Fe2O3 nanowires to ç-Fe2O3 nanowires is preliminarily studied by ab initio approach. It is found that the role of H2 is to change the Fe-O bonds in R-Fe2O3 nanowires, and then R-Fe2O3 is transformed into ç-Fe2O3.