Ricerc@Sapienza

Manganese ferrite nanoparticles were prepared by microwave-sonication assisted hydrothermal route and produced from wastes of Li-ion batteries and pyrite ash. The leaching solution of waste pyrite ash was used as the Fe source while the Mn-bearing solution recovered from the Li-ion battery recycling process was used as the Mn source. X-ray diffractometry showed that manganese ferrite can be obtained as single crystalline phase. Scanning electron microscope images showed that double-pyramid or octahedral particles were formed with an average size of 24.3 nm.

Here we discuss the incorporation of Cr(III) as dopant in the spinel lattice of the NiCo2O4cubic phase and its beneficial effect on the electro-catalytic activity of this material in aprotic Li-O2cells. To this aim, we synthesized highly porous carbon-free self-standing electrodes constituted by nanostructured undoped and Cr-doped NiCo2O4grown on open nickel mesh. These materials were characterized by X-ray diffraction, field emission scanning electron microscopy coupled with energy dispersive spectroscopy, transmission electron microscopy and X-ray photoelectron spectroscopy.