کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5491794 | 1525128 | 2017 | 17 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Surface functionalization of magnetite nanoparticle: A new approach using condensation of alkoxysilanes
ترجمه فارسی عنوان
کاربرد عملیات نانوذرات مگنتیت: یک رویکرد جدید با استفاده از تراکم آلکسی سیلان ها
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
فیزیک و نجوم
فیزیک ماده چگال
چکیده انگلیسی
In this study we report on successful production of two samples (BR15 and BR16) comprising magnetite (Fe3O4) nanoparticles (~10Â nm) surface-functionalized via hydrolysis and condensation of alkoxysilane agents, namely 3-aminopropyl-trimethoxisilane (APTS) and N-propyl-trimethoxisilane (NPTS). The as-produced samples were characterized using transmission electron microscopy (TEM), x-ray diffraction (XRD), magnetization measurements (5Â K and 300Â K hysteresis cycles and zero field-cooled/field-cooled measurements), and Mössbauer spectroscopy (77 and 297Â K). The Mössbauer data supported the model picture of a core-shell magnetite-based system. This material system shows shell properties influenced by the surface-coating design, either APTS-coated (BR15) or APTS+NPTS-coated (sample BR16). Analyses of the Mössbauer spectra indicates that the APTS-coated sample presents Fe(III)-rich core and Fe(II)-rich shell with strong hyperfine field; whereas, the APTS+NPTS-coated sample leads to a mixture of two main nanostructures, one essentially surface-terminated with APTS whereas the other surface-terminated with NPTS, both presenting weak hyperfine fields compared with the single surface-coated sample. Magnetization measurements support the core-shell picture built from the analyses of the Mössbauer data. Our findings emphasize the capability of the Mössbauer spectroscopy in assessing subtle differences in surface-functionalized iron-based core-shell nanostructures.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Physica B: Condensed Matter - Volume 521, 15 September 2017, Pages 141-147
Journal: Physica B: Condensed Matter - Volume 521, 15 September 2017, Pages 141-147
نویسندگان
A.F.R. Rodriguez, T.P. Costa, R.A. Bini, F.S.E.D.V. Faria, R.B. Azevedo, M. Jr, J.A.H. Coaquira, M.A.R. MartÃnez, J.C. Mantilla, R.F.C. Marques, P.C. Morais,