The Effect of Carbonaceous Material Morphology on Oxygen Reduction Reaction in Nonaqueous Electrolyte Containing Lithium Ions

The electrochemical characteristics of carbonaceous materials differing in their specific surface area and porosity are studied by the method of cyclic voltammetry in 0.25 М LiClO 4 /DMSO electrolyte, both in inert and oxygen atmosphere. The value of the electrochemically active surface area that was estimated from cyclic voltammograms as the polarization capacitance was shown to increase with increase in the BET specific surface area. The efficiency in the oxygen reaction, measured in the oxygen atmosphere and expressed as the charge consumed for the formation of Li 2 O 2 ( Q C ) in the oxygen reduction reaction (the cathodic segment), and the process reversibility, expressed as the ratio of the charge consumed for oxygen evolution ( Q A ) (the anodic segment) to Q C , are mainly determined by the electrochemically active surface area and the porosity of the carbonaceous material.