Size-dependent magnetic properties of Iron Carbide nanoparticles embedded in a carbon matrix

Here we report on the magnetic properties of iron carbide nanoparticles embedded in a carbon matrix. The granular distribution of nanoparticles in an inert matrix, of potential use in various application, were prepared by pyrolysis of organic precursors using thermal assisted chemical vapour deposition method. By varying the precursor concentration and preparation temperature, compositions with varying iron concentration and nanoparticle sizes were made. Powder X-ray diffraction, Transmission Electron Microscopy and MÄossbauer spectroscopy studies revealed, the nanocrystalline iron carbide (Fe3C) presence in the partially-graphitized matrix. The dependence of magnetic properties on the particle size and temperature (10 K<T