摘要
The relationship between the state of the surface of carbon nanotubes (CNTs) and their electrochemical activity was investigated using the enzyme cofactor dihydronicotinamide adenine dinucleotide (NADH) as a redox probe. The boiling of CNTs in water, while nondestructive, activated them toward the oxidation of NADH, as indicated by a shift in the anodic peak potential of NADH (ENADH) from 0.4 V to 0.0 V. The shift in ENADH was due to the redox mediation of NADH oxidation by traces of quinone species that were formed on the surface of treated CNTs. The harsher treatment that was comprised of microwaving CNTs in concentrated nitric acid had a similar effect on the ENADH, and, additionally, it increased the anodic peak current of NADH. The latter correlated with the formation of defects on the surface of acid-microwaved CNTs, as indicated by their Raman spectra. The increase in current was discussed, considering the role of surface mediators on the buckled graphene sheets of acid-microwaved CNTs. The other carbon allotropes, including the edge-plane pyrolytic graphite, graphite powder, and glassy carbon, did not display a comparable activation toward the oxidation of NADH.
摘要译文
吐温碳纳米管（CNT）和它们的电化学活性的表面的状态用的是酶辅助因子dihydronicotinamide腺嘌呤二核苷酸（NADH），为氧化还原探针研究。在水中的碳纳米管的沸腾，而无损，激活它们朝向NADH的氧化作用，如通过在NADH的氧化峰电位（E NADH）的移位，从0.4 V所示，以0.0 V.于E NADH的移位是由于NADH的氧化处理由碳纳米管的表面上形成该醌物种的痕迹的氧化还原调解。更严厉的处理被包括在浓硝酸微波CNT的也有类似的效果在E NADH，和，另外，它增加了NADH的阳极峰值电流。与缺陷酸微波CNT的表面上形成，后者相关，通过拉曼光谱所示。在当前的增长进行了讨论，考虑到表面介质的酸微波碳纳米管的屈曲石墨烯片的作用。其它碳同素异形体，其中包括边缘面内的热解石墨，石墨粉末，和玻璃碳，不显示可比较的活化朝向NADH的氧化。
Marilyn Wooten and Waldemar Gorski. Facilitation of NADH Electro-oxidation at Treated Carbon Nanotubes[J]. Analytical Chemistry, 2010,82(4): 1299-1304