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The generation of efficient, cheap and easily available water splitting catalysts, in particular for the oxygen evolution reaction (OER), is vital to the development of sustainable energy sources. Primary batteries, especially alkaline and Zn−C batteries, mostly end-up in landfill due to their short lifespan which aggravates health and poses environmental threats. To address these issues, this work establishes a sustainable route for the generation of Manganese oxide (Mn3O4) from spent Zn−C batteries as a catalyst for the OER under alkaline conditions. A thermal transformation study is conducted here at 900 °C and 800 °C under controlled atmosphere to generate Mn3O4 nanoparticles from waste Zn−C batteries which are investigated as a potential OER catalyst. Mn3O4 particle synthesis was confirmed by XRD, Raman, FTIR, TEM and EDS analysis. The electrochemical performance demonstrated a low overpotential of 360 mV to reach 10 mA cm−2 with a Tafel slope of 64 mV dec−1 indicating good activity under alkaline conditions. Thus, the generation of Mn3O4 from a spent Zn−C battery that can be employed as a catalyst for the OER is a promising path not only for the effective extraction of resources from battery waste, but also for the exploitation of using extracted materials in advanced technology applications.

End-of-life automotive waste contributes significantly to current environmental problems. Hence, developing new recycling solutions that can transform waste into new raw materials able to be used by the manufacturing industry should be investigated. This research details the novel technique of using high temperature processing of a mixture of automotive waste components and the ability to reform them into value-added materials including ferrosilicon alloy, silicon carbide (SiC) and silicon carbide (SiC)/silicon nitride (Si3N4) composites. Therefore, this research has created a new resource from automotive waste; which currently disposed of in landfill. The synthesized products from automotive waste, ferrosilicon alloy, SiC and SiC/Si3N4 composites can then be used across industrial applications. The synthesis are based on the reduction at temperatures of 1550 °C, with polymer (rubber tyre/Bakelite) as a carbon source and a reducing agent, iron oxide as a precursor, and automotive glass as a silicon source. Experimental lab-scale runs were carried out using a horizontal tube furnace under inert atmospheric conditions. Synthesized ferrosilicon alloy and SiC and SiC/Si3N4 composite were confirmed by XRD, EDS, Raman, XPS and ICP results, and the morphology was analysed by SEM. Associated reaction kinetics and the mechanism of reduction were investigated by an Infrared gas analyser. Rubber tyres and Bakelite demonstrated the potential to be used as a reduction material for silica reduction. Initial volatiles generated from the plastic accelerated the rate of silica reduction, particularly with the formation of SiC through gas phase reduction reactions of silica. Waste glass was also proven to be an alternative silica resource in synthesising value-added materials and showed process of metal separation from residual materials similar to silica. This process innovation has three significant advantages: 1. It is a major step toward transforming non-metallic automotive waste