Applications of Carbon Fiber Ultra-microelectrode and Powder Microelectrode in Exploring Influences of Non-aqueous Solvents and Cathode Materials on ORR and OER

Carbon fiber ultra-microelectrode was used to study the electrochemical reactions of O₂ in dimethyl sulfoxide, acetonitrile and tetraethylene glycol dimethyl ether. The results suggested that in tetrabutyl-ammonium-ion(TBA⁺)-containing electrolytes, the electrochemical reactions were reversible reactions of one-electron transfer; while in lithium-ion(Li⁺)-containing electrolyte, multiple-electrons transfer occurred during the oxygen reduction reaction(ORR) and oxygen evolution reaction(OER). Powder microelectrodes of super P and conductive acetylene black were used as working electrodes to conduct electrochemical experiments. The results showed the ORRs were similar, but the OER had differences on these two materials. Besides, Tafel analyses indicated that during the ORR, one-electron transfer always took place at first whether in different non-aqueous solvents or on different cathodes.