Amphiphilic bimetallic polymer as single-source precursors for the one-pot synthesis of L10-phase FePt nanoparticles

Abstract

Amphiphilic polymers have attracted extensive research attention in constructing various nanostructures by selfassembly. Here we designed and synthesized two amphiphilic bimetallic polymers with different length of the tails P1 and P2, in which Fe,Pt-containing conjugated complex acted as the hydrophobic block and hydrophilic poly(ethylene glycol) (PEG) was bonded to the bimetallic core as the flexible tails. P1 and P2 were used as the single-source precursors to prepare FePt nanoparticles (NPs) by one-pot pyrolysis. The resultant NPs were fully characterized and had a chemically ordered face-centered tetragonal (fct) phase with high crystallinity. The size of NPs pyrolyzed from P1 and P2 was 24.7 and 8.2 nm with the relative coercivity of 9.6 and 1.3 kOe, respectively. The difference was preliminarily explained by the discrepancy of their degrees of crystallinity, and also analyzed by the precursors' structural effect. The amphiphilic design showed a good potential in preparing monodisperse ferromagnetic FePt NPs, and the possible favorable properties of self-assembly might provide a bright venue for future magnetic recording media.

Metal-containing organic compounds for memory and data storage applications

“…After one-pot pyrolysis at 800 1C for 1 h under an Ar/H 2 atmosphere, L1 0 -FePt NPs with H c of 9.6 kOe and M s of 12.5 emu g À1 can be obtained. 214 Arrays of FePt NPs were prepared from bimetallic BCPs M8 templating, presenting phase-separated cylindrical or spherical FePt-containing nanodomains. After pyrolysis of the bulk samples at 800 1C, L1 0 -FePt NPs with average particle sizes of 4-8 nm were obtained.…”

Polymetallaynes and Molecular Metallaynes Containing Platinum, Mercury and Gold for Optoelectronic and Magnetic Applications

“…Amphiphilic metallopolymers 78a and 78b can be synthesized by attaching the hydrophilic poly(ethylene glycol) (PEG) chains to the hydrophobic bimetallic complex cores, in which the molecular weights of PEG chains are 550 and 1000, respectively. [ 73 ] The PEG tails can be utilized as the protective layer during pyrolysis while enable the NPs to disperse more evenly, suggesting that the particle size can be regulated by changing the length of the PEG chains to some extent. The average sizes of FePt NPs synthesized from 78a and 78b are measured to be 24.7 nm and 8.2 nm with the coercivities of 9.6 kOe and 1.3 kOe, respectively, and the higher coercivity of the former NPs is ascribed to their higher crystallinity.…”

Current Applications of Magnetic Nanomaterials for Extraction of Mycotoxins, Pesticides, and Pharmaceuticals in Food Commodities

“…Iron-platinum (FePt) are hard MNMs that have recently gained popularity amongst researchers due to the outstanding magnetic features they exhibit, such as great magnetocaloric effects, strong chemical stability, large saturation magnetization, magnetic imaging, and high magneto-crystalline anisotropy [ 81 , 82 , 83 ]. FePt magnetic materials are broadly applied in the biomedical field, magnetic data storage, large permanent magnet performance, electrocatalysis, nanobiotechnology, magnetic recording media, and biological research [ 84 , 85 , 86 , 87 ]. These alloys are synthesized through heat treatment (thermal decomposition) of Fe(Co) 5 (iron pentacarbonyl), polyol process (reduction of platinum acetylacetonate in a mixed surfactants and polyol), and reduction of Fe salts and Pt (acac) 2 [ 81 ].…”