Soft magnetic Fe-Co alloys have gained a lot of attention because of their possible application in high performance exchange-spring permanent magnets and several chemical strategies have been successfully explored in order to control composition, morphology, size and magnetic properties of Fe-Co NPs. Recently acoustic cavitation (primary sonochemistry) has been proposed for their synthesis leading mostly to formation of amorphous NPs.[1] In the present work we present our approach based on a modified surfactant-free polyol process promoted by secondary sonochemistry suitable for formation of crystalline NPs. XRD analysis of the obtained black precipitate ascertained formation of nanocrystalline Fe-Co material. TEM and HRTEM analysis revealed formation of cubic nanocrystalline Fe-Co NPs with size distribution in the range of 10 - 200 nm as expected in absence of surfactants. Fe-Co NPs showed MS values higher than 200 emu/g and extremely low coercivity. We are currently optimizing the synthesis and processing procedures and the results will be reported. This study has been supported by the NSF and the European IRSES NANOMAG Project N. 295190. References [1] K.S. SUSLICK, T. HYEON, M. FANG, Chem. Mater. 8, 2172 (1996)
Sonochemical synthesis and characterization of FeCo nanoparticles
Elisabetta Agostinelli;Elvira M Bauer;Davide Peddis;
2014
Abstract
Soft magnetic Fe-Co alloys have gained a lot of attention because of their possible application in high performance exchange-spring permanent magnets and several chemical strategies have been successfully explored in order to control composition, morphology, size and magnetic properties of Fe-Co NPs. Recently acoustic cavitation (primary sonochemistry) has been proposed for their synthesis leading mostly to formation of amorphous NPs.[1] In the present work we present our approach based on a modified surfactant-free polyol process promoted by secondary sonochemistry suitable for formation of crystalline NPs. XRD analysis of the obtained black precipitate ascertained formation of nanocrystalline Fe-Co material. TEM and HRTEM analysis revealed formation of cubic nanocrystalline Fe-Co NPs with size distribution in the range of 10 - 200 nm as expected in absence of surfactants. Fe-Co NPs showed MS values higher than 200 emu/g and extremely low coercivity. We are currently optimizing the synthesis and processing procedures and the results will be reported. This study has been supported by the NSF and the European IRSES NANOMAG Project N. 295190. References [1] K.S. SUSLICK, T. HYEON, M. FANG, Chem. Mater. 8, 2172 (1996)I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
