Polymer Mediated Self-Assembly of Magnetic Nanoparticles

Abstract

We present a simple polymer-mediated process of assembling magnetic FePt nanoparticles on a solid substrate. Alternatively absorbing the PEI molecule and FePt nanoparticles on a HO-terminated solid surface leads to a smooth FePt nanoparticle assembly with controlled assembly thickness and dimension. Magnetic measurements show that the thermally annealed FePt nanoparticle assembly as thin as three nanoparticle layers is ferromagnetic. The magnetization direction of this thin FePt nanoparticle assembly is readily controlled with the laser-assisted magnetic writing. The reported process can be applied to various substrates, nanoparticles, and functional macromolecules and will be useful for future magnetic nanodevice fabrication.

Spin valve sensors for ultrasensitive detection of superparamagnetic nanoparticles for biological applications

“…5(a), the bilayer lift-off process involves four steps: a bilayer of poly(ethylenimine) (PEI)/poly (methyl methacrylate) (PMMA) is sequentially coated onto the sensor surface (step 1). PEI is a functional polymer on which magnetic nanoparticles can self-assemble into a monolayer via ligand exchange between PEI and the surface surfactant (oleic acid) of the nanoparticles [27]. The PEI layer of ∼2 nm thickness is dip-coated in chloroform solution.…”

Surface Initiated Atom Transfer Radical Polymerization of N-Hydroxysuccinimide Methacrylate from Magnetite Surface as Precursor for Functional Polymer Shell

“…[9][10][11][12] Recently, surface initiated atom transfer radical polymerizations (ATRP) were successfully applied to prepare densely packed polymer layer onto magnetic nanoparticles. 13,14 The advantage of ATRP to surface-initiated polymerization is that it is relatively easy to perform in a living fashion.…”

Applications of synchrotron X-rays in microelectronics industry research

“…Monodisperse, well-oriented ferrolectric nanoparticles are good candidate materials for ultra-high density magnetic storage media of the future, possibly up to 20 Tbits/in. The sample was made by "polymer-mediated selfassembly [15]" and consisted of 4nm nanoparticles assembled layer-by-layer at room temperature.…”