Ethylene Glycol Electrooxidation on Phyto-synthesized Pd-Fe Composites by Aqueous Extract Plants

In the present work, the four Fe-based structures were prepared from the phyto-synthetic approaches and their subsequent calcinations. The aqueous extracts of Salsola sp. and Heliotropium bacciferum plants were used as the bio-reductant and stabilizer in these approaches. The green synthesized structures were characterized using FT-IR, XRD, FESEM, EDX, and VSM techniques. The characterization results showed that calcination created a cubic γ-Fe₂O₃ phase with spherical morphology. The preparation of Pd-Fe composites was completed by reducing palladium ions on iron-containing samples using Salsola sp. aqueous extract. The effect of calcination and the type of extract used in the synthesis of Pd-Fe composites on their electrocatalytic activity towards the electrooxidation of ethylene glycol by voltammetry technique. The catalyst prepared with Salsola sp. (2.35 mA.cm⁻²) extract had better catalytic activity than the one Heliotropium bacciferum (1.67 mA.cm⁻²) for 0.28 M ethylene glycol oxidation. The catalytic activity of iron in the not-calcined form was higher than in the calcined due to the transformation in the electronic structure, confirmed by the change in the magnetic behavior of the sample. This work highlights the importance of green synthesis methodologies in electrochemistry applications. In summary, the main advantages of this work are the principles of green chemistry followed by an eco-friendly approach, sustainable resource utilization, cost-effectiveness, and enhanced catalytic properties.

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