Magnetic properties of ceramics from the pyrolysis of metallocene-based polymers doped with palladium

Solution processing is a facile method to generate magnetic thin films. Polyferrocenylethylmethylsilane (PFEMS) was doped with palladium (II) acetylacetonate using two methods: sublimation of Pd(acac)2 to form Pd nanoparticles in the PFEMS films and direct mixing of Pd with the PFEMS polymer precursor prior to film deposition. These polymer composites all exhibit paramagnetic behavior, with increasing magnetic susceptibility for increasing Pd content. Pyrolysis of the precursors yields ferromagnetic ceramics at room temperature. The effect of the pyrolysis temperature and atmosphere on the magnetic properties, chemical composition, and crystalline structure of the ceramics was explored. For ceramics containing Pd, FePd alloys are observed to form pyrolyzed under argon at 1000 °C. The formation of these alloys results in enhanced coercivity, remanent magnetization, and saturation magnetization of the ceramics.