As the catalyst plays an essential role in benefiting the kinetics of ORR, a greater surface area means a greater electrochemical surface area (ESA) of the catalyst-the surface of the catalyst where molecules' absorption occurs. This enhances the catalyst's impact on the kinetics of the reaction. A higher ESA offers more active sites for catalytic reactions. These reactions include weakening the oxygen bond, which aids in breaking the bond and subsequently facilitates electron transfer upon interaction with the catalyst's ESA . Therefore, increasing the catalyst's surface area will create more ESAs with more collisions between the oxygen molecules and the catalyst, increasing the rate of reactions.