Structural and magnetic properties of MnZnO composites synthesized from waste alkaline and Zn/C batteries

M.V.GALLEGOS; M.A.PELLUSO; L.C. DAMONTE; J.SAMBETH

Simposio; 25th International Symposium on Metastable, Amorphous and Nanostructured Materials (ISMANAM 2018); 2018

Spent alkaline and zinc?carbon batteries were subjected to a biohydrometallurgyprocess, in order to recover manganese and mixed manganese zinc oxides. Theobtained products were used as starting materials for several new compositionalsystems containing manganese which crystallized in the spinel structure beingtheir structural and magnetic properties also studied.Two solids were synthesized, one of them prepared by chemical precipitation withNaOH (ZnMnR) and KMnO4 (OMR). The solids were filtered, washes with distilledwater, dried at 120 ºC and calcined in air at 500 ºC during 2 h. Mn and Zn contentwere determined by atomic absorption spectrophotometry (AAS) using a Varian AA240 spectrophotometer. Quantitative analysis of the composition of the sampleswere carried out with a scanning electron microscope provided with energy dispersiveX-ray analysis (SEM-EDS) using a Philips SEM 505 microscope. Preparedmaterials have been extensively characterized using transmission electron microscopy(TEM, JEOL JEM-100CXII), X-ray diffraction (XRD) and FTIR spectroscopy.Optical characterizations were carried out by measuring the diffuse reflectancespectroscopy. All spectra were taken in the range of 200-800 nm using a PerkinElmer Lambda 35 UV-vis spectrophotometer with integrating sphere attachment.The magnetic properties of the samples were measured by a Quantum DesignMPMS-5S superconducting quantum interference device (SQUID) magnetometerat different temperatures. The effect of Mn content on the optical and magneticproperties was analyzed in order to evaluate the use of the recovered materials fordifferent technological applications.