Fe-Phthalocyanine Nanoclusters on La_0.67Sr_0.33MnO₃ Ferromagnetic Substrate for Spintronics Application

Fe-Phthalocyanine (FePc) is a planar molecule made of an organic cage (pyrrole and benzene) and a central iron metal. The organic ligand permits to anchor the molecule on different supports, while the central atom reacts to gas exposure and its spin alignment changes according to the environment. We grew FePc nanostructures on La0.67Sr0.33MnO3 (LSMO) ferromagnetic substrates, which are optimal for investigating the concomitant FePc oxidation through oxygen atom termination and variation of the magnetic properties. The electronic and magnetic properties of FePc nanoclusters in contact with the LSMO surface and Co were studied through X-ray absorption and electron emission spectroscopies. The Fe oxidized at the FePc/LSMO interface and its magnetic response is compatible with the one of iron oxides. The adsorption of metallic Co onto the FePc leads to specific spectroscopic features that are fingerprints of the following scenario: (i) Co nanoclusters in contact with LSMO or FePc nanoclusters and (ii) Co inserted into FePc molecules due to the transmetalation process. The overall magnetic response at low temperature is probed by VSM, manifests a maximum in the magnetization curve, and is explained in terms of the Co/FePc nanocluster interaction. The synthesis and investigation of these hybrid nanostructures open up horizons for applications in both catalysis, nanomagnetism, and spintronics due to the intriguing and challenging electronic and magnetic response of metal organic/oxides interfaces.