Long term research interest in zinc aqueous metal-air batteries have achieved the development of potentially high energy density and safe batteries. Nowadays, Pt is the most used catalyst employed for ORR (oxygen reduction reaction) in metal-oxygen batteries. This wide use of the Pt as catalyst avoids the application of Zinc metal-air batteries at industrial scale due to the large price and scarcity of the components. Due to these shortcomings, the research of alternative catalyses has become a thematic of world-wide interest.
One alternative is the use of transition metals instead of the Pt metal, mainly oxides and nitrides of this transition metal due to its relative abundance and low cost. One of the most promising elements of this group is the Mn. Manganese nitrides and oxides can act as a bifunctional catalyst for the ORR and OER (oxygen evolution reaction). However, the obtention of the Mn nitrides usually requires extensive thermal treatments with high energy demand, around 1100 °C.
This study proposes the synthesis via sol-gel method assisted by multiple organic products and utilization of manganese chloride as a precursor. The final product was then examined by SEM (scanning electron microscopy), XRD, FTIR and Raman analysis. Finally, the materials were assembled in a Zn-air El-Cell test battery and analysed by Cyclic Voltammetry, Galvanostatic charge-discharge and impedance analysis.