ABSTRACT
Nanocomposites based on porous silicon (Por-Si) with 3d-metals incorporated into pores can be used as magnetics. Por-Si layers were obtained by anodic etching of n-type silicon (100) with the use of HF solution in alcohol. Fe, Co, Ni galvanic deposition in por-Si was made from aqueous solutions of corresponding sulphates. We have shown by USXES (Ultrasoft X-ray emission spectroscopy), and Auger spectroscopy that Fe covers the surface of porous silicon uniformly but Co penetrates into pores depth. And Ni nanoparticles similar to Co penetrate into pores depth. The obtained Auger profiles of por-Si(Fe), por-Si(Co), por-Si(Ni) nanocomposites shown that its surface layers (to 40 nm) contain up to 10% Fe and no more than 1% Co and Ni, testifying about Co and Ni penetration into silicon pores depth.
Subject(s)
Crystallization/methods , Metal Nanoparticles/chemistry , Metal Nanoparticles/ultrastructure , Silicon/chemistry , Spectrometry, X-Ray Emission/methods , Macromolecular Substances/chemistry , Materials Testing , Molecular Conformation , Particle Size , Porosity , Surface PropertiesABSTRACT
The X-ray photoelectron spectroscopy was used for studying the dependence of the 3d-metal spin state in nanoforms on the nanoform chemical structure. For studying the nanoform chemical structure a model developed by us was used, which allowed to find out the interrelation between the parameters of the X-ray electron 3s spectra of transition metals and the number of uncompensated electrons in metal atoms. It is shown that the nanoform chemical structure is determined by the methods used for their preparation and by the nanoreactor form. By changing the structure of nanoforms it is possible, to a certain extent, to control magnetic characteristics of nanoform-based materials.
