การพัฒนาขั้วไฟฟ้าจากการวาดด้วยดินสอบนกระดาษทรายสำหรับหาปริมาณแคดเมียมในน้ำ

Development of Pencil Drawn Electrodes on a Sand Paper for Cadmium Analysis in Water Puttiphat Benjapreechaphat, Nuanlaor Ratanawimarnwong, and Preecha Mansalaiรับบทความ: 6 ตุลาคม 2560; ยอมรับตีพิมพ์: 25 ธันวาคม 2560DOI: http://doi.org/10.14456/jstel.2018.8 บทคัดย่อในงานวิจัยนี้นำเสนอวิธีการที่ง่ายและราคาประหยัดสำหรับการเตรียมอิเล็กโทรเคมิคัลเซนเซอร์ เพื่อใช้ในการวิเคราะห์หาปริมาณแคดเมียมในน้ำ โดยการใช้ขั้วไฟฟ้าแกรไฟต์อย่างง่ายซึ่งผลิตขึ้นจากไส้ดินสอที่ฝนบนกระดาษทราย เมื่อนำขั้วไฟฟ้าแกรไฟต์ที่ผลิตได้มาใช้ร่วมกับเทคนิคสแควร์เวฟอาโนดิกสทริปปิงโวลแทมเมตรี พบว่า มีประสิทธิภาพในการวิเคราะห์หาปริมาณแคดเมียมที่มีปริมาณน้อยได้ จากการศึกษาปัจจัยต่าง ๆ ที่ส่งผลต่อสัญญาณที่ตรวจวัดได้ที่สภาวะที่เหมาะสมให้ช่วงความเป็นเส้นตรงของกราฟมาตรฐานตั้งแต่ 5 µgL-1 ถึง 100 µgL-1 ขีดจำกัดในการตรวจวัดเท่ากับ 0.72 µgL-1 อิเล็กโทรเคมิคัลเซนเซอร์นี้ประสบความสำเร็จในการนำไปประยุกต์ใช้สำหรับการวิเคราะห์แคดเมียมในตัวอย่างน้ำโดยตรง คำสำคัญ: แคดเมียม ขั้วไฟฟ้าจากการวาดด้วยดินสอ สแควร์เวฟโวลแทมเมตรี Abstract This research presented a simple and low-cost approach for electrochemical sensor preparation to determine cadmium in water. The approach employed a simple graphite electrode made of pencil lead via mechanical abrasion onto a sand paper. When using the developed graphite electrode to square-wave anodic stripping voltammetry, the capability for trace analysis of cadmium was observed.  Influence of several relevant operating parameters was also investigated.  At the optimum condition, linear range of 5 µgL-1 to 100 µgL-1 was provided and detection limit of 0.72 µgL-1 was achieved. The proposed sensor was successfully applied for the direct determination of cadmium in water samples. Keywords: Cadmium, Pencil drawn electrodes, Square wave voltammetr

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