Agglomeration and sintering in annealed FePt nanoparticle assemblies studied by small angle neutron scattering and x-ray diffraction

Abstract

In this work we give a detailed account of the use of small angle neutron scattering to study the properties of polymer mediated, self assembled nanoparticle arrays as a function of annealing temperature. The results from neutron scattering are compared with those obtained from x-ray diffraction. Both techniques show that particle size increases with annealing temperatures of 580°C and above. They also show that the distribution of particle diameters is significant and increases with annealing temperature. The complementary nature of the two measurements allows a comprehensive structural model of the assemblies to be developed in terms of particle sintering and agglomeration. To realise the potential of nanoparticle assemblies as a monodispersed data storage medium the problem of particle separation necessary to avoid sintering and agglomeration during annealing must be addressed.

A Polyferroplatinyne Precursor for the Rapid Fabrication of L10‐FePt‐type Bit Patterned Media by Nanoimprint Lithography

“…Inevitably, some defects such as sintering, agglomeration, broad size distribution, etc, will be concomitant with this method. [6,7] The reason for these problems could be attributed to the fact that the elements Fe and Pt are originally in separate compounds which have different onset decomposition temperatures. Hence, some organometallic complexes containing both Fe and Pt atoms for use as a single source precursor were synthesized and applied to generate the L1 0 phase FePt NPs by the one-step decomposition.…”

Size‐Dependent Chemical and Magnetic Ordering in L10‐FePt Nanoparticles

“…A major hurdle in obtaining the particle size dependence of structural and magnetic properties of the L1 0 phase is particle sintering during heat-treatments that convert the fcc phase to the fct phase. [13,14] This long-pending problem has been solved recently by adopting the salt-matrix annealing technique. [15,16] With this technique, particle aggregation during the phase transformation has been avoided so that the true size-dependent properties of the fct phase can be measured.…”

Investigation of pyrolysis temperature in the one-step synthesis of L10 FePt nanoparticles from a FePt-containing metallopolymer

“…H NMR (CDCl 3 , 400 MHz, d/ppm): 7.37-7.34 (m, 6H, Ar-H), 7.04-6.99 (m, 6H, Ar-H),6.82 (d, J ¼ 16 Hz, 1H, CH]CH), 6.67 (d, J ¼ 16 Hz, 1H, CH]CH), 4.47 (s, 2H, Fc-H), was stirred overnight under a nitrogen atmosphere at room temperature. The completion of the reaction was veri-ed by spot TLC.…”