Abstract: Efficient electrocatalytic rupture of energy-rich molecules (H₂ and O₂) is a green approach for generating clean energy for modern societies. In this context, porphyry-type molecular electrocatalysts act intelligently toward oxygen reduction reaction (ORR), a fundamental process in fuel cells, due to their redox-rich chemistry, which involves core metal ions and macrocyclic ligands. The concerned scientific community has tried many times to correlate the ORR intermediates with their formation kinetics and simplify the associated multi H⁺/e^- stages during the ORR process, constructing several volcano plots between catalytic Tafel data, turnover frequencies, and overpotentials for many electrocatalysts. Despite the fact that many review articles on molecular electrocatalysts for ORR have been published, understanding the strategic implications and molecular catalyst intelligence towards homogenous ORR has been poorly explored. This review examined the relationships between volcano plots of current vs. thermodynamic parameters and the Sabatier principle in order to explain the intelligence of molecular electrocatalysts and approaches for their creation, as well as the difficulties and potential prospects of molecular electrocatalysts. These facts distinguish this review from previously published articles and will pique the scientific community's interest in avoiding trial-and-error procedures for catalyst creation while also allowing for more exact evaluations of the molecular catalyst's performance.

Key words: Electrocatalysis, Molecular catalysts, Oxygen reduction reaction, Sabatier principle