Vibration sample magnetometry, a good tool for the study of nanomagnetic inclusions

The accurate determination of the ferromagnetic contribution in a composite in which the ratio of the ferromagnetic part vs. the total of composite is 10⁻⁴–10⁻⁵ is a problem of great importance in relation to the development of new materials in our days. In this work, the potential of Vibration Sample Magnetometry (VSM) in the identification and quantification of nanomagnetic inclusions is illustrated and discussed in three different cases: PbFe₁₂O₁₉/ Al₂O₃ thin films, nanopowders of magnetite in a polymeric matrix, and carbon nanotubes with iron inside in a silica matrix (Fe/ CN_x/ SiO₂). In all cases, the determination of the existence of preferential orientation, the correct quantification of the magnetic part, and the dependence of the coercive field with on synthesis conditions were revealed using this technique.