Date of Award

June 2021

Degree Type


Degree Name

Master of Science



First Advisor

Woo-Jin Chang

Committee Members

Yongjin Sung, Benjamin Church


Ammonium molybdate, Electrochemical sensing, Phosphate detection, Screen-printed electrode


This research implies making a noble low cost-effective electrochemical sensor based on the fabrication of AM (Ammonium Molybdate) and Py (Pyrrole) nanocomposite to detect phosphate in water. The developed sensor was tested with various concentrations of phosphate solutions in a wide range of pH (pH 6-pH 7.5) to determine the sensitivity and lower detection limit. With the lowest detection limit of 10-11 mol/L, an Ammonium Molybdate and Pyrrole (AM-Py as a layer) nanocomposite modified screen-printed electrode (SPE) produced the best signal using the open-circuit voltammetry (OCV) method. To observe the pH effect on the proposed sensor, it was tested with the phosphate buffer solutions (range from pH 6-pH 7.5). The signals from open circuit voltammetry were analyzed, and the related parameters were optimized. In comparison to the complex and time-consuming electrochemical synthesis process, the established sensor's structure and fabrication method are quick and easy to follow. Furthermore, for low-cost mass manufacturing, this fabrication process can be easily changed and implemented using a printing unit. The developed electrochemical sensor, according to the findings, has the ability to detect phosphate anion with a high precision rate.