A systematic study of the influence of nanoelectrode dimensions on electrode performance and the implications for electroanalysis and sensing.
A systematic study of the influence of nanoelectrode dimensions on electrode performance and the implications for electroanalysis and sensing.
复制标题
系统研究纳米电极尺寸对电极性能的影响以及对电分析和传感的影响。
作者：
I. Schmueser;Anthony J Walton;J. Terry;Helena L Woodvine;Neville J Freeman;Andrew R. Mount
微米分辨率光刻技术已被用于制造微平方纳米带边缘电极阵列（MNEE），该阵列具有可重复性和系统控制的关键尺寸参数，包括阵列元件的尺寸和间距以及纳米电极厚度。首先建立了这些阵列的响应，这些阵列可以在商业规模上重复制造。由此产生的特性（包括高信号和信噪比，低检测极限，对外部对流不敏感，快速，稳态，可重复性和定量响应）使这种纳米带电极阵列成为真正感兴趣的增强型电分析设备。特别是，纳米电极响应作为纳米尺度电极尺寸的函数进行了呈现和分析，以评估先前假设的纳米尺寸效应对结果响应的影响和相对贡献。这项工作表明，在带边缘的迁移对传质有重要贡献，即使在离子强度高达0.7 mol dm（-3）和电极宽度为50 nm时，也会影响所得的电分析响应。对于5nm纳米带，额外的纳米效应，被认为是由于氧化还原物质的大小与带宽相当的事实，也被观察到衰减观察到的电流。这给电极性能的基本见解，并讨论了随之而来的影响，使用这种纳米尺寸的电极。
Micron resolution photolithography has been employed to make microsquare nanoband edge electrode (MNEE) arrays with reproducible and systematic control of the crucial dimensional parameters, including array element size and spacing and nanoelectrode thickness. The response of these arrays, which can be reproducibly fabricated on a commercial scale, is first established. The resulting characteristics (including high signal and signal-to-noise, low limit of detection, insensitivity to external convection and fast, steady-state, reproducible and quantitative response) make such nanoband electrode arrays of real interest as enhanced electroanalytical devices. In particular, the nanoelectrode response is presented and analysed as a function of nanometre scale electrode dimension, to assess the impact and relative contributions of previously postulated nanodimensional effects on the resulting response. This work suggests a significant contribution of migration at the band edges to mass transfer, which affects the resulting electroanalytical response even at ionic strengths as large as 0.7 mol dm(-3) and for electrodes as wide as 50 nm. For 5 nm nanobands, additional nanoeffects, which are thought to arise from the fact that the size of the redox species is comparable to the band width, are also observed to attenuate the observed current. The fundamental insight this gives into electrode performance is discussed along with the consequent impact on using such electrodes of nanometre dimension.