Gong Kuanping, Zhang Meining, Yan Yiming, Su Lei, Mao Lanqun, Xiong Shaoxiang, Chen Yi
Center for Molecular Science, Institute of Chemistry, the Chinese Academy of Sciences, Beijing 100080, China.
Anal Chem. 2004 Nov 1;76(21):6500-5. doi: 10.1021/ac0492867.
Nanocomposite electrodes made of sol-gel-derived ceramic-carbon nanotube are fabricated by doping mutliwalled carbon nanotubes (MWNTs) into a silicate gel matrix. The electrochemical behavior and potential electrochemical applications of the ceramic-carbon nanotube nanocomposite electrodes (CCNNEs) are also studied. The as-prepared CCNNEs exhibit a tunable dimension ranging from conventional electrode to nanoelectrode ensemble (NEE), depending on the amount of the MWNT dispersed in the silica sol and finally doped within the gel matrix. A high content of the MWNT (i.e., higher than 1.5 mg/mL in the sol) leads to the formation of the CCNNE characteristic of an electrode of conventional dimension, while a low content (typically lower than 0.10 mg/mL) essentially yields the CCNNE like a nanoelectrode ensemble. The NEE is demonstrated to possess good electrocatalytic activity toward the oxidation of ascorbic acid (AA), and the CCNNE of conventional dimension is found to possess remarkable electrocatalytic activity toward the oxidation of glutathione (both reduced and oxidized forms, GSH and GSSG). These properties of the CCNNEs essentially offer a new electrochemical approach for the detection of AA, GSH, and GSSG. The possible essence of the tailor-made dimensions of the CCNNEs is also presented and discussed.
通过将多壁碳纳米管（MWNTs）掺杂到硅酸盐凝胶基质中，制备了由溶胶 - 凝胶衍生的陶瓷 - 碳纳米管制成的纳米复合电极。还研究了陶瓷 - 碳纳米管纳米复合电极（CCNNEs）的电化学行为和潜在的电化学应用。根据分散在硅溶胶中并最终掺杂在凝胶基质中的MWNT的量，所制备的CCNNEs呈现出从传统电极到纳米电极阵列（NEE）的可调尺寸范围。MWNT的高含量（即溶胶中高于1.5mg/mL）导致形成具有传统尺寸电极特征的CCNNE，而低含量（通常低于0.10mg/mL）基本上产生类似于纳米电极阵列的CCNNE。已证明NEE对抗坏血酸（AA）的氧化具有良好的电催化活性，并且发现传统尺寸的CCNNE对谷胱甘肽（还原型和氧化型，GSH和GSSG）的氧化具有显著的电催化活性。CCNNEs的这些性质基本上为检测AA、GSH和GSSG提供了一种新的电化学方法。还介绍并讨论了CCNNEs定制尺寸的可能本质。
