Single-step chemical synthesis of ferrite hollow nanospheres.
We report a single-step chemical synthesis of iron oxide hollow nanospheres with 9.3 nm in diameter. The sample presents a narrow particle diameter distribution and chemical homogeneity. The hollow nature of the particles is confirmed by HRTEM and HAADF STEM analysis. Electron and x-ray diffraction show that the outer material component is constituted by 2 nm ferrite crystals. Mössbauer data provide further evidence for the formation of iron oxide with high structural disorder, magnetically ordered at 4.2 K and superparamagnetism at room temperature. An unusual magnetic behavior under an applied field is reported, which can be explained by the large fraction of atoms existing at both inner and outer surfaces.
Centro Atómico Bariloche and Instituto Balseiro, 8400 SC de Bariloche, RN, Argentina.
Enio
E
Lima
José M
JM
Vargas
Roberto D
RD
Zysler
Hercilio R
HR
Rechenberg
Renato
R
Cohen
Jordi
J
Arbiol
Gerardo F
GF
Goya
Alfonso
A
Ibarra
M Ricardo
MR
Ibarra