A shortcut to organize self-assembled monolayers of cobalt ferrite nanoparticles on silicon

We report a successful synthetic strategy to covalently assemble a monolayer of CoFe2O4 nanciparticles on a silicon substrate using undecanoate as molecular linker. The nanocrystals of ferrite are coated with a protecting layer of undecanoate which beyond stabilizing the nanoparticles allows their organization on silicon directly reacting with Si-H surface through its vinyl end group. The organic coat was obtained during the synthesis of cobalt ferrite using sodium undecanoate as protective agent. This synthetic strategy avoids the exchange monolayer reaction generally required to bind the NPs on the substrate. The structural and magnetic characterizations of monolayer self-assembled nanoparticles on silicon surface are reported.