Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/15105
標題: 拋棄式電鍍金屬網版印刷電極在分析化學的應用
Electroanalysis based on disposable metal-plated screen-printed carbon electrodes
作者: 楊智超
Yang, Chih-Chio
關鍵字: screen-printed electrode;網版印刷電極;metal;電鍍金屬
出版社: 化學系
摘要: 
本論文主要的研究方向是以網版印刷電極(Screen-printed electrode, SPE)電鍍不同金屬應用於分析化學。論文一開始先對於網版印刷電極的製備及電化學分析方法做一簡單介紹。第二章的研究是利用預氧化網版印刷電極修飾汞薄膜(HgSPE*)偵測鉛離子(Pb2+),並將此方法實際應用在真實血樣中的分析,在偵測的過程中加入內標準品(Internal standard)鉈(Tl3+),以提高準確度及減少偵測時間,最後與石墨爐原子吸收光譜(GFAAS)做比對得到很好的結果。第三章則接續第二章的研究,希望將偵測血中鉛的研究繼續推展下去,我們將所有的儀器、電極都將之微小化,血樣前處理的方式也更為簡單,期望能發展出一套可實際偵測勞工血鉛濃度的分析工具,利用簡易的操作系統及工具微小化的方式使的應用層面更加的廣泛。第四章是對於水中溶氧含量偵測的研究,我們在前面的研究發現以預氧化的方式能夠產生碳氧官能基(例如,>C=O),而在本章節發現此官能基能夠有效的將金屬穩定於電極表面上,因此以此手法處理電極表面再將鈀(Pd)電鍍於電極表面上,對於氧氣還原反應得到很好的效果,最後以此電極分析地下水與自來水中的含氧量,最後與市售的溶氧度計做比對得到相當接近的結果。我們利用電鍍的手法將金屬還原至網版印刷電極表面的技術已經相當成熟,第五章則是利用網版印刷電極電鍍銅(Cu)及鈀(Pd),藉由表面分析技術來瞭解不同的電鍍方式及排列順序,致使合金(Alloy)的形成有所不同,進而影響對於分析物的偵測結果,我們以網版印刷電極修飾奈米銅鈀合金粒子(SPE/Cu-Pd)對於聯胺(Hydrazine)做偵測,最後測得線性範圍為2 ─ 100 uM,計算其靈敏度和回歸係數分別為0.21 uA/uM和0.999,最後實際應用在香菸煙草中聯胺的偵測。

We report here a highly accurate and efficient method for blood lead analysis (BLA) through the use of a disposable electrode. A new type of mercury-plated preanodized screen-printed carbon electrode, together with a thallium(III) internal standard, simplifies calibration and gives easily quantifiable signals for accurate BLA. A preanodization procedure improves the preconcentration ability of the working electrode through the effect of lead (Pb) complexing with an electrogenerated surface functional group, mainly
>C=O. Under optimized conditions, the ratio of the anodic stripping peak currents of Pb and Tl (i.e., iPb/iTl) is linear against [Pb] in
the window of 1-300 ppb with a correlation coefficient and detection limit (signal-to-noise ratio = 3) of 0.999 and 0.23 ppb, respectively. This approach was used to analyze blood samples (n = 55) from workers at a local battery factory. The results are consistent with those obtained from graphite furnace atomic absorption spectroscopy and confirm the applicability of the proposed method.
Efficient and stable electrocatalytic activity for the reduction of O2 at activated screen-printed carbon electrodes modified with palladium nanoparticles (SPE*-Pd) was demonstrated in this study. X-ray photoelectron spectroscopy confirmed the formation of >C=O functional group on electrode surface during the preanodization procedure at 2.0 V (vs. Ag/AgCl). The existence of chloride moieties was also identified possibly from the organic binder of carbon
ink used in SPE fabrication. Both >C=O and chloride functional groups were essential for the excellent stability of the SPE*-Pd. Electrochemical impedance spectroscopy verified the enhanced kinetic rate of oxygen reduction reaction at the as-prepared Pd nanoparticles. The SPE*-Pd showed ca. 250 mV positive shift in peak potential together with twice increase in peak current compared to those observed at a SPE-Pt. The calibration plot was linear up to 8 ppm of DO with sensitivity and regression coefficient of 4.49 mA/ppm and 0.9936, respectively. The variation coefficient of ipc for 7 DO determinations with O2-saturated pH 7.4 PBS was 2.1%. Real sample assays for ground and tap waters gave consistent values to those measured by a commercial dissolved oxygen meter.
The preparation of copper-palladium alloy nanoparticle plated screen-printed carbon electrodes (SPE/Cu-Pd) and their use for the electrocatalytic determination of hydrazine in pH 7.4 phosphate buffer solution is described. X-ray photoelectron spectroscopic study indicates that the SPE/Cu-Pd prepared by successive electrochemical deposition of Cu and Pd is possessed of strong perturbed electronic interaction with a high Pd/Cu atomic ratio. Flow injection analysis of hydrazine using the SPE/Cu-Pd shows a linear detection range of 2-100 uM at an applied potential of +0.2V
versus Ag/AgCl with a current sensitivity and relative standard deviation of 0.21 uA/uM and 1.86%, respectively. The detection limit (S/N = 3) was 270 nM. Quantitative detection of hydrazine in cigarette tobacco was further demonstrated using the proposed electrode.
URI: http://hdl.handle.net/11455/15105
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