Effect of surface roughness and surface modification of indium tin oxide electrode on its potential response to tryptophan
Effect of surface roughness and surface modification of indium tin oxide electrode on its potential response to tryptophan
复制标题
氧化铟锡电极表面粗糙度和表面修饰对其色氨酸电位响应的影响
DOI：
10.1016/j.electacta.2011.07.068
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发表时间：
2011
影响因子：
6.6
通讯作者：
T.Osaka
中科院分区：
文献类型：
--
作者：
M.Z.H.Khan;T.Nakanishi;S.Kuroiwa;Y.Hoshi;T.Osaka
针对不同表面粗糙度的ITO基板，研究了氧化铟锡（ITO）电极的表面修饰对其色氨酸电位响应的影响。结果发现，通过原子力显微镜评估，表面粗糙度在~1和~2nm之间的微小差异会影响ITO电极在电解质中的剩余电势。通过角分辨 X 射线光电子能谱和俄歇电子能谱测量，ITO 基板近表面的 In:Sn 比率存在轻微差异，这一差异非常显着，并且被认为与表面粗糙度有关。有趣的是，用氨基丙基硅烷和二琥珀酰亚胺基辛二酸酯对ITO表面进行连续修饰，这对于我们之前报道的吲哚化合物的电位响应至关重要，提高了剩余电位的稳定性，并使电极能够在Ra值范围在~2和~3nm之间的样品中对色氨酸做出响应，但对于Raof~1nm的样品则不然。提出ITO对色氨酸的特异性电位响应的有效功函数存在最佳值，可以通过对ITO表面的连续修饰来获得。
The effect of surface modification of indium tin oxide (ITO) electrode on its potential response to tryptophan was investigated for ITO substrates with different surface roughness. It was found that a small difference in surface roughness, between ∼1 and ∼2nm of Raevaluated by atomic force microscopy, affects the rest potential of ITO electrode in the electrolyte. A slight difference in In:Sn ratio at the near surface of the ITO substrates, measured by angle-resolved X-ray photoelectron spectrometry and Auger electron spectroscopy is remarkable, and considered to relate with surface roughness. Interestingly, successive modification of the ITO surface with aminopropylsilane and disuccinimidyl suberate, of which essentiality to the potential response to indole compounds we previously reported, improved the stability of the rest potential and enabled the electrodes to respond to tryptophan in case of specimens with Ravalues ranging between ∼2 and ∼3nm but not for those with Raof ∼1nm. It was suggested that there are optimum values of effective work function of ITO for specific potential response to tryptophan, which can be obtained by the successive modification of ITO surface.