The simplicity of synthesis of polymer nanocomposites together with elasticity and plasticity, make these materials attractive in the aspect of possible applications for different application, including electronics and sensors, like different rectifiers and switching devices based on their high nonlinear VAC (volt-ampere characteristics) and tendency to form Schottky diodes, transistors, nanowires. Recent progress in spintronic and application of nanocomposites in that area have been shown in the work of Y. Liu, et al. [1,2]. Distinct attention in than and other investigations was attracted to the spin-valves, which use the effect of giant or tunneling magnetoresistance. Typically these devices consist on three-layer system: nonmagnetic layer is sandwiched between two ferromagnetic (hard and soft) of those. Based on these systems scanning heads of magnetic plates and magnetoresistance memory elements were produced. Usually the polymer materials were used as interlayer material between two ferromagnetic layers (hard and soft), while the adaptation of ferromagnetic polymer nanocomposites with embedded magnetic atoms (Ni, Co, Fe) will allow to construct spin-valve structures based on the homogeneous material, introducing a number of technological advantages. For the fabrication of these heterostructures the study of physical properties, like magnetoresistive effects, including anomalous Hall effect demonstrating the evidence of spin polarization of charge carriers have to be performed together with the correlation between these effects and the structure of material. The coercive force can be changed by pinning of the ferromagnetic stage with antiferromagnetic inclusions.

In this work we present the results of electron microscopy and microanalysis study of Ni-poly-p-xylylene nanocomposites stuffed with Ni nanoparticles in 5 – 30 vol. % range of concentration. The magnetic and electrophysical properties for these samples are slightly above the percolation threshold and strongly above it.

1. Liu, Yaohua; Watson, Shannon M.; Lee, Taegweon; Gorham, Justin M.; Katz, Howard E.; Borchers, Julie A.; Fairbrother, Howard D.; Reich, Daniel H., Physical Review B, 2009. V. 79. 075312 

2. «Structure and optical properties of thin poly(p-xylylene) – silver nanocomposite films prepared by low–temperature vapor deposition polymerization» Dmitry R. Streltsov, Karen A. Mailyan, Alexey V. Gusev, Ilya A. Ryzhikov, Yury I. Kiryukhin, Anton S. Orekhov, Alexander L. Vasiliev, Natalia A. Erina, Andrey V. Pebalk, Yaroslav I. Odarchenko, Dmitri A. Ivanov, and Sergei N. Chvalun // POLYMER 71:60-69 · AUGUST 2015

Figures:

Sample with C=9wt% Ni. (a). BF HRTEM image of hcp Ni particle in [1120] zone axis. Note the absence of structural defects in the particle. (b) - the FFT power spectra from the particle and (c) - simulated electron diffraction pattern of hcp-Ni in [1120] zone axis.

BF TEM images of the nanocomposite (a)- with C = 5 vol% of Ni and (b)- 30 vol% of Ni.

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EMC Abstracts - https://emc-proceedings.com/abstract/structure-characteristic-of-ni-poly-p-xylylene-nanocomposites-synthesized-by-vdp/