纳米碳管电极上氧的电催化还原

Electrocatalytic Reduction of Oxygen on Carbon Nanotubes Electrode

以聚四氟乙烯为粘结剂制成了多壁纳米碳管(MWNT)电极.采用恒电位阶跃法和循环伏安法研究了MWNT电极在碱性溶液中的电化学行为,并对碱性溶液中溶解氧在该电极上的电化学还原行为进行了研究.实验结果表明:MWNT电极具有比石墨电极更高的孔隙率和电化学表面积;MWNT电极上O2还原成HO2-的反应为准可逆过程;在5～50mV·s-1的扫描速率范围内,阴极峰电流与扫描速度成线性关系,表明MWNT电极上O2还原成HO2-的反应受吸附控制;对碱性溶液中的氧还原反应,MWNT比石墨具有更高的催化活性.

The multi-walled carbon nanotube(MWNT) electrode was constructed using poly-tertrafluoroethylene as binder. The electrochemical behavior of the MWNT electrode in alkaline solution was investigated by chronoamperometry and cyclic voltammetric method, and the electrochemical reduction of dissolved oxygen in alkaline solution was examined on this electrode. Experimental results showed that MWNT electrode had higher porosity and electrochemical surface area than graphite electrode. The reduction of O-2 to HO2- on MWNT electrode was a quasi-reversible process, and cathodic peak currents depended linearly on the scan rate over the range of 5 similar to 100 mV (.) s(-1), which suggested that the process of the electrode reaction was controlled by the adsorption. The significant differences in voltammetry between the MWNT electrode and the graphite electrode for dissolved oxygen in alkaline solution indicated that MWNT had higher electrocatalytic activity than graphite powders.