應用於檢測水溶液中金屬離子之微電漿裝置之設計

The Design of Microplasma Generation Device for Detection of Metallic Ion in Aqueous Solution

楊馥瑜(Fu-Yu Yang)

指導教授 ： 徐振哲

國立臺灣大學/工學院/化學工程學研究所/碩士(2018年)

https://doi.org/10.6342/NTU201802965

摘要

本研究應用電漿可用來激發原子及分子使其放光之特點，搭配光譜儀之使用，取得放光光譜並從光譜中分析水溶液中重金屬的成分資訊。本研究共設計2個可以在大氣下操作之微電漿裝置，設計一為簡單之針尖之水溶液之系統，利用不鏽鋼大頭針為正極，待測水溶液為負極。設計二為新穎的濾紙系統產生電漿之設計，此設計利用銅膠帶及滴上水溶液之濾紙當作電極。
此二系統之電漿產生皆是透過一9 V之電源供應器連接一升壓之高壓模組輸出約3 kV之電壓給系統能量。針尖至水溶液系統電漿之產生是由於高速電子之撞擊產生一系列產生電漿反應，並由瞬間之高溫使待測物氣化進入電漿區，藉由激發-鬆弛現象放光。濾紙系統之設計則是利用濾紙之各個位置之電流密度不同，造成每個地方之沸騰氣化速度差異，最快被氣化完全而水溶液又來不及補充之位置就會因電阻高於其他位置，而讓提供之電壓全部落於此處，造成此處生成電漿，電漿伴隨燃燒造成氣化之待測物也有激發並放光之現象。經由光譜儀取得上述二者之放光光譜，再比對每個元素之特徵波長，即可分析出待測物之成分。
本研究除了設計兩種系統進行比較外，也透過改變系統中之不同變因試圖找出兩種裝置之最適化條件來進行實驗。目前透過針尖至水溶液之系統以及濾紙系統，分別可用來偵測到最低500 ppm及200 ppm之含鉛水溶液。如何再使偵測極限降低以及如何定量分析是我們之後努力之目標。

關鍵字

微電漿 ； 重金屬檢測 ； 光譜分析

並列摘要

In this study, we use the feature that plasma can excite atoms to excited state then emit the lights. With optical emission spectrometer, we can get the information from spectrum. In this study, we design two kinds of devices which can be operated in atmosphere. One of device is pin-to-surface, that use stainless steel pin as positive and solution as negative. The other one is a novel design, that use copper tape and filter paper with solution as electrode. In these two system, the plasma is produced by 9 V power supplier connecting a high voltage module and give around 3 kV to system. Plasma of pin-to-surface system results from impact of high speed electrons, causing high temperature gasification. Gas enter plasma zone and get excited.
By comparing characteristic peak of each element, we can analysize the compositions of samples. In addition to compare these two system, we try to find suitable condition for the two systems. The lowest concentration of copper solution that can be detected is 500 ppm and 200 ppm for pin to surface and novel filter paper design, respectively. How to reduce the detect limit and how to quantitative analysis are our final goals.

並列關鍵字

Microplasma ； Heavy metal detection ； spectrum analyze

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