Exploring Discharged Dry Cell as an Electrocatalyst for Oxygen Evolution Reaction

High oxophilic d-block compounds of dry cell based manganese materials such as MnO2, Mn3O4, and ZnxMn3O4􀀀x have excellent electrocatalytic property in oxygen evolution reaction (OER). To seek a way for disposing these dry cell materials, which are unlike rechargeable batteries, these discharged cells result in environmental hazards. Here we optimized these manganese oxides for an energy related applications, particularly for OER. With this aim, we have examined electrocatalytic behavior of both used and fresh dry cells in OER. We have observed that the used dry cell material exhibited 10 mA. cm􀀀2 at an overpotential of 525 mV but fresh dry cell needed 100 mV higher overpotential to achieve same current density. The nature of these fresh and used materials have been analyzed using XRD, SEM, TGA, Raman spectra, FT-IR and contact angle experiments. The higher activity of used dry cell could be ascribed to the generation of highly active Mn3O4 from MnO2 and graphene oxide while discharging conditions.