Corrosion-Resistant Hybrid Nanoparticles of Polydimethylsiloxane@Fe Obtained by Thermolysis of Fe(CO)₅

Thermal decomposition of iron pentacarbonyl, Fe(CO)₅, in the presence of small amounts of polydimethylsiloxanes (PDMSs) leads to a hybrid aggregate of pure nanosized (about 10 nm) zero-valent iron nanoparticles (PDMS@Fe) with remarkable corrosion-resistance properties even after three months of immersion in saline solution. Various tests, including potentiodynamic polarization measurements and impedance spectroscopy, were carried out in a 3.5 wt.-% NaCl solution; the results indicate a corrosion protection efficiency (η, %) of up to 99.7 % and an iron corrosion rate estimation of 3 μm per year. Detailed characterization of the materials, including Mössbauer spectroscopy and magnetization measurements, was used to provide a mechanism for the remarkable corrosion inhibition properties of this PDMS-doped iron nanohybrid.