鉻具有高毒性，其主要型態為三價鉻(Cr(III))及六價鉻(Cr(VI))，六價鉻具有較高的毒性及使生物致突變性，因此快速和準確地檢測鉻離子已成為一個關鍵問題。本研究利用電鍍沉積法製備金奈米粒子/單壁奈米碳管複合材料修飾玻璃碳電極(Au/SWCNT/GCE)進行水中重金屬鉻物種之伏安法分析。首先選定電鍍金奈米粒子沉積至單壁奈米碳管電極之操作條件及模擬水樣分析目標重金屬Cr(VІ)與Cr(III)最佳參數條件，接著以最佳條件分析目標重金屬作相關性的探討。結果顯示Au/SWCNT/GCE在不同pH電解液條件下，可辨別Cr(VІ)與Cr(III)，以線性掃描伏安法(LSV)分別測Cr(VІ)與Cr(III)，兩者濃度與其電流值皆得到良好線性關係 (R2 > 0.995)，方法定量極限為0.2和0.4 mg L-1。後續分別添加其他重金屬銅、鉛、鎘、鋅以及在不同環境水樣進行干擾測試，探討其他重金屬以及水體對干擾目標重金屬分析之可能性與適用性。結果顯示此複合材料修飾電極感測器進而應用在環境監測上是具有可行性的發展。

Chromium is considered to be highly toxic, especially hexavalent chromium(Cr(VI)). Fast and accurate detection of chromium ions has become a critical issue. In this study, the gold nanoparticles/single-walled carbon nanotubes modified glassy carbon electrode (Au/SWCNT/GCE) was fabricated for chromium detection through voltammetry. The gold nanoparticles were deposited single-walled carbon nanotube film via electroplating. The deposition time and precursor concentration were optimized. The scanning conditions, such as supporting electrolyte, pH, and scanning velocity were also determined. The results show that Cr(VI) and Cr(III) can be distinguished from Au/SWCNT/GCE under different pH electrolytes. Linear sweep voltammetry (LSV) determination reveals that there exists a good linear relationship between the peak current and the concentration with the limits of quantification of 0.2 and 0.4 mg L−1, respectively. The interferences of other heavy metal ions, such as Cu (II), Pb (II), Cd (II), and Zn (II) are investigated. Then, the possibility and applicability of the target heavy metals were discussed in different environmental water samples. Voltammetric measurement using Au/SWCNT/GCE electrodes affords a fast, simple and sensitive detection of trace amounts of chromium.

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