In the present study, I conducted a digital simulation analysis of the electrochemistry of O2/O2 •-in the presence of H2Q in DMF (Scheme 2), focusing on the three elementary steps of 2PCET. As shown in Scheme 2, electrogeneration of O2 •-(1) triggers a series of homogeneous 2PCET (steps (i)-(iii)) and heterogeneous reactions of the products. The obtained voltammograms demonstrate heterogeneous electrode reactions of FR, PRC, PC, and FP, from which homogeneous solution reactions involving the three elementary steps were inferred. Accordingly, I investigated the details of the electrochemical reduction of O2 in the presence of H2Q using digital simulation analyses to gain deeper mechanistic insight into 2PCET between O2 •-and H2Q.