Article Title

Green and low temperature synthesis of nanocrystalline transition metal ferrites by simple wet chemistry routes

Authors

Stefano Diodati, Istituto per l’Energetica e le Interfasi, IENI-CNR and INSTM, UdR di Padova, via Marzolo, 1, I-35131, Padova, Italy
Luciano Pandolfo, Dipartimento di Scienze Chimiche, Università degli Studi di Padova, via Marzolo, 1, I-35131, Padova, Italy
Andrea Caneschi, Laboratory of Molecular Magnetism, LAMM Dipartimento di Chimica e UdR INSTM di Firenze, Polo Scientifico, Via della Lastruccia, 3, 50019, Sesto Fiorentino (FI), Italy
Stefano Gialanella, Dipartimento di Ingegneria Industriale, Università degli Studi di Trento, via Mesiano 77, I-38123, Trento, Italy
Silvia Gross, Istituto per l’Energetica e le Interfasi, IENI-CNR and INSTM, UdR di Padova, via Marzolo, 1, I-35131, Padova, Italy Dipartimento di Scienze Chimiche, Università degli Studi di Padova, via Marzolo, 1, I-35131, Padova, Italy

Keywords

ferrites, hydrothermal, low temperature, wet chemistry, green

Abstract

Crystalline and nanostructured cobalt (CoFe2O4), nickel (NiFe2O4), zinc (ZnFe2O4) and manganese (MnFe2O4) spinel ferrites are synthesized with high yields, cry- stallinity and purity through an easy, quick, reproducible and low-temperature hydrothermal assisted route starting from an aqueous suspension of coprecipitated metal oxalates. The use of water as a reaction medium is a further advantage of the chosen protocol. Additionally, the zinc spinel is also prepared through an alternative route combining coprecipitation of oxalates from an aqueous solution with thermal decomposition under reflux conditions. The nanocrystalline powders are obtained as a pure crystalline phase already at the extremely low tem- perature of 75 °C and no further thermal treatment is needed. The structure and microstructure of the prepared materials is investigated by means of X-ray powder diffraction (XRPD), while X-ray photoelectron spectroscopy (XPS) and inductively coupled plasma–atomic emission spectroscopy (ICP–AES) analyses are used to gain information about the surface and bulk composition of the samples, respectively, confirming the expected stoichiometry. To investigate the effect of the synthesis protocol on the morphology of the obtained ferrites, transmission electron microscopy (TEM) observations are performed on selected samples. The magnetic properties of the cobalt and manganese spinels are also investigated using a superconducting quantum device magnetometer (SQUID) revealing hard and soft ferrimagnetic behavior, respectively.

Graphical Abstract

DOI

https://doi.org/10.1007/s12274-014-0466-3

Publisher

Tsinghua University Press

Recommended Citation

Stefano Diodati,Luciano Pandolfo,Andrea Caneschi,Stefano Gialanella,Silvia Gross, Green and low temperature synthesis of nanocrystalline transition metal ferrites by simple wet chemistry routes. NanoRes.2014, 7(7): 1027–1042