Composition study of FePt nanoparticles synthesized from modified polyol process

338-342F<span style="mso-bidi-font-size: 15.0pt;mso-bidi-language:TH" lang="EN-GB">ive different conditions for modified polyol processes using iron(III) acetylacetonate and platinum(II) acetylacetonate as starting materials reveal significantly different products in terms of composition. The initial Fe:Pt molar ratio is not retained in the final products and Pt-rich nanoparticles are obtained from 1:1 molar ratio of Fe:Pt sources. The imbalance between Fe and Pt indicate that the nanoparticles formation can be explained by the heterocoagulation mechanism rather than the binary nucleation model. The increase in refluxing time and initial Fe:Pt molar ratio improved the amount of Fe in nanoparticles. However, the highest molar ratio of 3:1 apparently affected the uniformity of particles. The co-existence of iron oxide and Pt-rich nanoparticles is clearly evident in the case of 3:1 molar ratio combined with 1,2 hexadecanediol as a reducing agent. </span

FePt3 nanosuspension synthesized from different precursors – a morphological comparison by SAXS, DLS and TEM

Annealed iron-platinum (FePt) is ferromagnetic in a nanoscale regime which is necessary for energy and data storage, whereas the as-synthesized form of FePt-based nanoparticles exhibits superparamagnetism useful for biomedical applications. In this study, as-synthesized nanosuspensions from the reaction of Pt(acac)2 with Fe(acac)3 and Fe(hfac)3 are compared. X-ray diffraction (XRD) peaks for both samples are assigned to the FePt3 phase. As shown by transmission electron microscopy (TEM) and small angle X-ray scattering (SAXS), nanoparticles synthesized by using Fe(acac)3 have a smaller average diameter, but larger polydispersity index and particle agglomerations. On the other hand, the nanoparticles synthesized by using Fe(hfac)3 can self-assemble into a longer range of patterned monolayer. Dynamic light scattering (DLS), measuring the size of cluster of nanoparticles as well as oleic acid and oleylamine at their surface, confirms that larger agglomerations in the sample were synthesized by using Fe(acac)3. In addition to the size distribution, magnetic properties were influenced by the composition of these nanoparticles