TY - JOUR
T1 - Core-shell Au/Fe3O4 nanocomposite synthesized by thermal decomposition method
T2 - Structural, optical, and magnetic properties
AU - Oliveira-Filho, G. B.
AU - Atoche-Medrano, J. J.
AU - Aragón, F. F.H.
AU - Mantilla Ochoa, J. C.
AU - Pacheco Salazar, David Gregorio
AU - da Silva, S. W.
AU - Coaquira, J. A.H.
N1 - Publisher Copyright:
© 2021 Elsevier B.V.
PY - 2021/10/15
Y1 - 2021/10/15
N2 - Core-shell structure Au@Fe3O4 nanoparticles was synthesized via a thermal decomposition method, evidencing through interplanar atomic distances of ~ 0.23 nm and ~ 0.48 nm finding in the center and the shell of the particles, matching to the (1 1 1) Au and (1 1 1) magnetite planes, respectively. The nanocomposite has an average diameter of the core of ~ 10.5 nm and a thickness of the shell of ~1.85 nm, accessed by TEM. X-ray diffraction carried out on the sample shows the crystal structure of fcc Au and fcc Fe3O4 without a spurious crystalline phase. Besides, Rietveld refinement displays an outer diameter of ~ 8.1 and ~ 12.3 for the core and shell, respectively, the latter using the Scherrer constant of 0.9 and 1.43, respectively. The UV–vis characterization result shows a surface plasmon resonance spectra of Au@Fe3O4 nanoparticles at ~ 540 nm, which advise a successful core–shell coupling of Au and the Fe3O4. Finally, the magnetic response displays a system with a superparamagnetic state at room temperature and with a distribution of blocking temperatures associated with the enhanced surface contribution related to the hollow magnetite structure's inner and outer surface. From the mean TB, the effective magnetic anisotropy Keff1.7×104 J/m3 was obtained, which is in agreement with the expected for the magnetite phase.
AB - Core-shell structure Au@Fe3O4 nanoparticles was synthesized via a thermal decomposition method, evidencing through interplanar atomic distances of ~ 0.23 nm and ~ 0.48 nm finding in the center and the shell of the particles, matching to the (1 1 1) Au and (1 1 1) magnetite planes, respectively. The nanocomposite has an average diameter of the core of ~ 10.5 nm and a thickness of the shell of ~1.85 nm, accessed by TEM. X-ray diffraction carried out on the sample shows the crystal structure of fcc Au and fcc Fe3O4 without a spurious crystalline phase. Besides, Rietveld refinement displays an outer diameter of ~ 8.1 and ~ 12.3 for the core and shell, respectively, the latter using the Scherrer constant of 0.9 and 1.43, respectively. The UV–vis characterization result shows a surface plasmon resonance spectra of Au@Fe3O4 nanoparticles at ~ 540 nm, which advise a successful core–shell coupling of Au and the Fe3O4. Finally, the magnetic response displays a system with a superparamagnetic state at room temperature and with a distribution of blocking temperatures associated with the enhanced surface contribution related to the hollow magnetite structure's inner and outer surface. From the mean TB, the effective magnetic anisotropy Keff1.7×104 J/m3 was obtained, which is in agreement with the expected for the magnetite phase.
KW - Core-shell nanoparticles
KW - Effective magnetic anisotropy
KW - Superparamagnetism
KW - Surface plasmon resonance
UR - http://www.scopus.com/inward/record.url?scp=85108309189&partnerID=8YFLogxK
U2 - 10.1016/j.apsusc.2021.150290
DO - 10.1016/j.apsusc.2021.150290
M3 - Artículo
AN - SCOPUS:85108309189
VL - 563
JO - Applied Surface Science
JF - Applied Surface Science
SN - 0169-4332
M1 - 150290
ER -