Summary: | 碩士 === 國立成功大學 === 化學系碩博士班 === 94 === The α-Fe2O3 (hematite) nanopropellers were synthesized via a low temperature solution-based method using FeCl2 as a precursor in the presence of urea and glycine hydrochloride. The formation of α-Fe2O3 nanopropellers is strongly depended on the addition of glycine hydrochloride, which serves as a pH modulator and affects the oxidation rate of Fe2+. The structural evolution of the propeller-structured hematite was found to follow dissolution and recrystallization processes. For the structural conformation, each nanopropeller presents a hexagonal central column closed by six equivalent surfaces of {1100} and the six arrays of the nanopropeller structure are a result of growth along ± [1100], ± [1010], and ± [0110]. Preliminary results show that the magnetic maghemite (γ-Fe2O3) nanopropellers could also be prepared by a reduction and re-oxidation process from the α-Fe2O3 (hematite) nanopropeller precursors.
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