Water splitting has been one of the potential techniques as a clean and renewable energy resource for the fulfillment of world energy demands. One of the major aspects of this procedure is the exploitation of efficient and inexpensive electrocatalysts due to the fact that the water oxidation procedure is accompanied by a delayed reaction. In this research, ZnO-CoFe₂O₄ nanostructure was successfully synthesized via the green method and green resources from cardamom seeds and ginger peels for oxygen evolution reaction (OER). The modified Glassy carbon electrode (GCE) with ZnO-CoFe₂O₄ is effective for the electrochemical water oxidation interaction since it has sufficient electrical strength and excellent catalytic performance. The creation of rice-like and small granular structures of ZnO-CoFe₂O₄ nano-catalysts was confirmed by characterization methods such as XRD, FESEM, EDS and MAP. According to the achieved results, in the electrolysis of water, with in-cell voltage of 1.40 V and 50 mA cm^–2 for current density in a 0.1 M KOH electrolyte and OER only has 170 mV overpotentials.

green synthesis; nanoparticles; ZnO-CoFe2O4; cardamoms; ginger peels

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