The present work aimed to optimize the preparation of activated carbons (ACs) from two main precursors, used in our city (chicken bone, CB and cashew nut shells, CNS). The ACs were prepared according to the chemical and physical activation. A central composite design based on the response surface methodology was employed to determine the optimal conditions for producing activated carbons. The results showed that for the production of optimized materials, the operating conditions were a carbonization temperature of 800 \(\:^\circ C\:\) and 690 \(\:^\circ C\) an activation time of 30 and 49 min, for CB and CNS, respectively, and a NaOH concentration of 60%. Based on the XRD results, both materials showed an amorphous graphitic structure. Both materials demonstrated a good BET specific surface area, especially that of the activated carbon made from chicken bones. These values were 551.57 and 282.21 m2/g for CB and CNS, respectively. Moreover, the materials were applied in the electrogeneration of oxygen gas based on the oxygen evolution reaction (OER) analyses in 1 M KOH electrolyte. The CNS electrocatalyst showed an oxygen overvoltage of 605 mV at 10 mA cm−2. While, the CB material exhibited a relevant performance with an oxygen overvoltage of 398 mV at 10 mA cm−2, a Tafel slope of 198 mV/dec, and good stability. These results show that CB materials can be considered as effective electrocatalysts for new green energy systems.
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