Mass transport limitations also play a critical role in the sluggish OER rate, particularly in systems with high current densities or poor electrolyte conditions . The diffusion of reactants (e.g., water or hydroxide ions) to the active sites and the removal of products (e.g., oxygen gas) from the reaction interface can create concentration gradients, reducing the effective reaction rate . Inadequate supply of reactants leads to local depletion near the electrode, while inefficient removal of oxygen gas can cause bubble formation, which hinders active site accessibility and reduces the electrochemical surface area. This dynamic introduces additional resistances, exacerbating the overpotential required to sustain the reaction.