Manganese oxide synthesized from spent Zn-C battery for supercapacitor electrode application

Manganese oxide (Mn3O4) nanomaterials have promising potential to be used as supercapacitor electrode materials due to its high energy storage performance and environmental compatibility. Besides, every year huge volume of waste batteries including Zn-C battery ends up in landfill, which aggravates the burden of waste disposal in landfill and creates environmental and health threat. Thus, transformation of waste battery back into energy application, is of great significance for sustainable strategies. Compared with complex chemical routes which mostly apply toxic acids to recover materials from Zn-C battery, this study establishes the recovery of Mn3O4 particles via thermal route within 900 degrees C under controlled atmosphere. Synthesized Mn3O4 were confirmed by XRD, EDS, FTIR, XPS and Raman analysis and FESEM micrographs confirmed the coexistence of spherical and cubic Mn3O4 particles. Mn3O4 electrode derived from waste Zn-C battery demonstrate compatible electrochemical performance with standard materials and conventional synthesis techniques. Mn3O4 electrode exhibited highest capacitance value of 125 Fg(-1) at 5 mVs(-1) scan rate. The stability of the electrode showed good retention in discharge and charge capacity by about 80% after 2100 cycles. This study demonstrates that waste Zn-C battery can be further utilized for energy storage application, providing sustainable and economic benefits.