Electrocatalytic oxidation and reduction of H2O2 on vertically aligned Co3O4 nanowalls electrode: Toward H2O2 detection
Electrocatalytic oxidation and reduction of H2O2 on vertically aligned Co3O4 nanowalls electrode: Toward H2O2 detection
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DOI：
10.1016/j.jelechem.2008.09.020
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发表时间：
2009-01-01
影响因子：
4.5
通讯作者：
Lei, Yu.
中科院分区：
文献类型：
--
作者：
Jia, Wenzhao;Guo, Min;Lei, Yu.
在常温条件下，在热板上直接加热Co箔，合成了单晶和垂直排列的Co3O4纳米壁。垂直排列的Co3O4纳米壁生长在板上，表现出优异的力学性能，并通过导电银漆很容易地附着在玻碳（GC）电极表面。将制备的Co3O4纳米壁电极应用于过氧化氢（H2O2）在0.01 M pH 7.4磷酸盐缓冲介质中的电催化氧化还原研究。当H2O2加入后，Co3O4纳米壁电极在+0.25 V （vs. Ag/AgG）左右开始出现H2O2的明显氧化还原，而在裸GC电极上，在大部分电位范围内未观察到明显的氧化还原活性。这种优异的电催化反应主要归因于合成的Co3O4纳米壁表面积大、扩散阻力小、表面能高、电子转移增强。同样的Co3O4纳米壁电极也应用于H2O2的安培检测，分别在+0.8 V和-0.2 V （vs. Ag/AgCl）电位下具有快速响应和高灵敏度。结果还表明，Co3O4纳米壁在传感器和生物传感器方面具有巨大的应用潜力。Elsevier B.V.出版
Single crystal and vertically aligned cobalt oxide (Co3O4) nanowalls were synthesized by directly heating Co foil on a hot-plate under ambient conditions. The vertically aligned Co3O4 nanowalls grown on the plate show excellent mechanical property and were facilely attached to the Surface of a glassy carbon (GC) electrode using conductive silver paint. The prepared Co3O4 nanowalls electrode was then applied to study the electrocatalytic oxidation and reduction of hydrogen peroxide (H2O2) in 0.01 M pH 7.4 phosphate buffer medium. Upon the addition of H2O2, the Co3O4 nanowalls electrode exhibits significant oxidation and reduction of H2O2 starting around +0.25 V (vs. Ag/AgG), while no obvious redox activity is observed at a bare GC electrode over most of the potential range, The superior electrocatalytic response to H2O2 is mainly attributed to the large surface area, minimized diffusion resistance, high surface energy, and enhanced electron transfer of the as-synthesized Co3O4 nanowalls. The same Co3O4 nanowalls electrode was also applied for the amperometric detection of H2O2 and showed a fast response and high sensitivity at applied potentials of +0.8 V and -0.2 V (vs. Ag/AgCl), respectively. The results also demonstrate that Co3O4 nanowalls have great potential in sensor and biosensor applications. Published by Elsevier B.V.