化學需氧量 COD 是用來檢測水中有機物污染程度的一個重要指標，而電化學伏安法分析相較於傳統分析方法有著高靈敏度，低成本，適合現場監測以及對環境具有友善性等優點，因此相對於重鉻酸鉀迴流法而言，極具有未來的發展性。本研究探討利用金奈米粒子/二氧化鈦/單壁奈米碳管複合材料修飾電極進行線性掃描伏安法分析 (LSV)，並選用鄰苯二甲酸氫鉀 (KHP)、水楊酸、葡萄糖、單乙醇胺 (MEA) 作為COD之模擬水樣，在其濃度範圍2-250 ppm內進行分析，分析所得的峰電流值與濃度的線性關係，共分為兩區段，分別為2-90 ppm以及100-250 ppm，而2-90 ppm區段相較於100-250 ppm區段有較好的線性關係存在，並發現LSV圖譜會因為模擬水樣的化學結構不同，其所得到的電流氧化峰值位置而不同。將該修飾電極進行再現性分析，其相對誤差為8.826 %，最後使用KHP作為COD模擬水樣，比較在不同濃度下利用LSV與CODcr偵測方法所得到數值之間的關係，發現其變化數值有相同的趨勢。;Chemical oxygen demand (COD) is an important index for detecting the level of organic pollution in water. Voltammetry, an electrochemical analysis, which has many advantages including high sensitivity, low cost, suitable for on-site monitoring, and environmental friendly. When compared to traditional standard method (potassium dichromate reflow method), using electrochemical method for the COD analysis has the development potential. In this research, from 2 to 250 ppm of the potassium hydrogen phthalate (KHP), salicylic acid, glucose, and monoethanolamine (MEA) are selected as a standard aqueous sample of COD to investigate the linear relationship between the peak current and the concentration through the linear sweep voltammetry analysis (LSV) with the GNPs/TiO2/SWCNT modified electrode. The linear relationship is divided into two sections, one is from 2 to 90 ppm and the other one is from 100 to 250 ppm. It can be found the R square of the 2-90 ppm segment is higher than the 100-250 ppm segment. In addition, the LSV curves are different in each of the organic compounds because of the different chemical structures. The reproducibility of the modified electrode is analyzed with a relative error of 8.826%. Finally, the KHP is used as a standard aqueous sample and the COD value obtained by the LSV and by CODcr at different concentration is compared. The relationship between concentration and COD can be found on both these two methods and the trends are the same.
