Surface Modification of Chemically Synthesized FePt Nanoparticles

Abstract

L1 0 -FePt nanoparticle having high magnetic anisotropy is a promising candidate for the future ultra high magnetic recording material. We have succeeded in the fabrication of cubical FePt nanoparticles. It is necessary for high areal recording density to develop a homogeneous assembled technique of the cubical nanoparticle with its magnetic easy axis in the vertical direction on a substrate. It has been known the selective chemical reaction between metal species and functional group of organic molecules. We focused on the selective chemical reaction to control the direction of the magnetic easy axis in the cubical nanoparticle. In this study, the modification of the organic molecule with various functional groups to the surface of the cubical nanoparticle was examined. Consequently, the amino groups were replaced by thiol groups and carboxyl groups on the surface ligands of the nanoparticle were residual, and then, we confirmed bonding thiol group end to Pt atom selectively.

The mechanism underlying the functionalisation of cobalt nanoparticles by carboxylic acids: a first-principles computational study

“…4. Considering that the available literature on the binding of carboxylic ligands to monometallic and bimetallic NPs and surfaces reports the bridging bidentate as the preferred mode of interaction in most cases with the occasional dominance of the chelate biding, [71][72][73][74][75] it is likely that the proposed functionalisation mechanism, or certain aspects of it, are also applicable to those systems. The true mechanisms for the acid functionalisation of other metallic NPs are, however, subject to future research efforts.…”

(Invited) Development on Self-Assembly Technique for Arrangement of Chemically Synthesized FePt Nanoparticles

“…For application as-synthesized FePt nanoparticles to BPM, we attempted to develop a simple process to control the distortion of the FePt array using chemical synthesis and geometrical grid prepared by ultraviolet nanoimprint lithography (UV-NIL). Previously, we succeeded in the fabrication of cubic FePt nanoparticles by controlling the reaction temperature in chemical synthesis; the FePt nanoparticles were immobilized by using chemical bonding on a thermal oxide Si substrate with modified (3-mercaptopropyl)trimethoxysilane, MPTMS as an interlayer between the FePt nanoparticles and the Si(100) substrate (14,15). The model image is shown in Fig.…”

New Proposal for the Interfacial Design toward the Establishment of Electrochemical Device Engineering

“…We have been investigating the nanoparticles of functional materials, 6 synthesized as a zero-dimensional system, often with focusing our attention on the application of their two-or three-dimensional assembly and/or dispersion with the use of their properties, e.g., magnetic nanoparticles for data storage, [28][29][30] catalytic nanoparticles for fuel cells, 31 and plasmonic nanoparticles for biosensing. 32 Design of the interface between nanoparticles and solution should contribute to the uniformity and quality of zero-dimensional building blocks and then control the functionality of their two-or three-dimensional assembly or dispersion.…”

“…Following to the achievement of controlled synthesis of FePt nanoparticles in view of interfacial design, 28,29 we are investigating the immobilization of nanoparticles with ordered orientation and arrangement, on the basis of design and control of the interface between FePt nanoparticles and SiO 2 /Si substrate by using the organosilane SAM formed from mercaptopropyltrimethpxysilane. 30 For Biomaterials Magnetite (Fe 3 O 4 ) nanoparticles have been attracting much interest because of their biocompatibility and wide use in medical and diagnostic applications such as magnetic resonance imaging, drug delivery system, cell separation, and hyperthermia. 33 It was demonstrated that the size of secondary particles, or aggregation of magnetite nanoparticles, as well as their surface charge affect the efficiency of their uptake into cells.…”