| 摘要: | 重金屬鎘具有高毒性，若人體攝入過多的鎘，可能會導致骨骼、腎功能、呼吸系統的危害。目前分析重金屬的方式耗時長、樣品需要前處理、且無法即時反應水質狀況，然而電化學伏安法由於操作方便、便宜、簡單、快速、能即時分析等優點而受到重視。本研究開發氧化石墨烯/單壁奈米碳管/碲化鉍修飾玻璃碳電極進行方波陽極析出伏安法分析水中的鎘。首先選定適宜的伏安法掃描方式，再進行材料配比的比較及確認，經過參數最佳化後(電解液pH 5、沉積電位-1.1 V)，探討該修飾電極在120 s和360 s偵測鎘(II)的性能，同時也對該電極的穩定性進行評估。結果顯示，氧化石墨烯/單壁奈米碳管/碲化鉍修飾電極使用方波陽極析出伏安法偵測鎘(II)呈現良好的線性關係，在沉積電位120 s的情況下，LOD為0.99 µg/L；在沉積電位360 s的情況下，LOD為0.14 µg/L，遠低於放流水標準(20–30 µg/L)和飲用水標準(5 µg/L)，而重複性及再現性分別為0.5%和3.7%。另外，經過測試該電極不會受到水中Pb(II)、Zn(II)、Cr(III)、Cr(VI)、As(III)、As(V)的干擾，不過由於Cu(II)的還原電位較低，因此鎘的剝離電流易受到高濃度銅的影響，最後本研究在環境水體中進行鎘(II)的分析，證實了在自來水及地下水中有良好的回收率。;Cadmium is highly toxic and ingestion by humans may harm to humans, such as bone, kidney function, and respiratory system. At present, the method of analyzing heavy metals require pretreatment and long time so it cannot give the results of water quality promptly. However, electrochemical voltammetry is valued due to its advantages of convenient operation, low cost, simplicity and rapid analysis. In this study, determination of Cd(II) by square wave anodic stripping voltammetry using graphene oxide/single-walled carbon nanotubes/Bi2Te3 modified glassy carbon electrode was developed. First, the appropriate voltammetric scanning method is selected, and then the SWCNT/GO ratio was confirmed. The performance of the modified electrode in detecting Cd(II) at 120 s and 360 s was investigated after parameter optimization (electrolyte pH 5, deposition potential -1.1 V). The stability of the electrode was also evaluated. The results showed that the GO/SWCNT/Bi2Te3/GCE can successfully determine Cd(II) by SWASV. At a deposition potential of 120 s, the LOD is 0.99 μg/L; at a deposition potential of 360 s, the LOD is 0.14 μg/L, which is lower than the effluent standard (20–30 μg/L) and the drinking water standard (5 μg/L). Repeatability and reproducibility were 2.6% and 3.7%, respectively. Moreover, the electrode developed in this work is also free from the interference of Pb(II), Zn(II), Cr(III), Cr(VI), As(III), As(V) in water, but the stripping current of Cd(II) is easily affected by high concentration copper due to the low reduction potential of Cu(II). Finally, the analysis of Cd(II) in environmental waters confirmed the good recovery in tap water and groundwater. |
