Fine Tuning of the Sizes of FePt Nanoparticles

Abstract

Fine tuning of the sizes of FePt nanoparticles has been realized by a simple modification of a solution phase synthesis, which consists of the decomposition of Fe(CO)5 and the reduction of Pt(acac)2. The key method used to control the particle size is the use of surfactants, and only a change in their amount is required to vary the average sizes of the FePt nanoparticles from 2 to above 4 nm. The resultant nanoparticle volume is proportional to the surfactant amount; this makes the synthesis of FePt nanoparticles of desired sizes possible.

Direct synthesis and characterizations of fct-structured FePt nanoparticles using poly(N-vinyl-2-pyrrolidone) as a protecting agent

“…Thus, the effect of PVP could be considered as follows: Since PVP cannot strongly bind but weakly coordinate to the surface of nanoparticles, the FePt nanoparticles can grow up at rather small R. However, the growth of FePt nanoparticles stops when R is larger than 6 in the case of using PVP as a protecting agent. This fact is different from the case of using oleic acid and oleylamine as protective reagents [57]. In the case of using low molecular weight ligands as a protective reagent, the size in diameter of FePt nanoparticles increases with increasing the amount of them.…”

Recent Advances in Chemical Synthesis, Self‐Assembly, and Applications of FePt Nanoparticles

“…[28] Alternatively, to make larger FePt particles, a seed-mediated growth method is used. [26] This is performed by first making monodisperse 3-4 nm seed FePt particles, and then adding more Fe and Pt precursors to enlarge the existing FePt particle seeds to obtain the desired sizes.…”

Dispersible Ferromagnetic FePt Nanoparticles

“…[1] Such NPs, with controlled magnetic properties, have great potential for ultrahigh-density information-storage [2][3][4] and high-performance permanent-magnet applications. [5][6][7][8][9] Monodisperse FePt NPs have been produced by solution-phase chemical decomposition of iron pentacarbonyl (Fe(CO) 5 ) and reduction of platinum acetylacetonate (Pt(acac) 2 ), [10][11][12][13] or by co-reduction of an iron and a platinum salt. [14][15][16][17][18][19] As synthesized, the FePt NPs have a chemically disordered face-centered cubic (fcc) structure, and are superparamagnetic at room temperature.…”