Phosphate Sensor Using Molybdenum

Aphosphate ion-selective electrode (ISE) based on molybdenum was developed, which is based on the reaction between molybdenum and hydrogen phosphate ions (HPO42-) in alkaline condition. We found that the electrode showed a near Nernst characteristics with a slope of -26.9 +/- 0.5 mV/decade. Potential linear range is from 10(-1) M to 10(-5) M and detection limit is 1.9 x 10(-6) M in the pH of 8.5. The short response time for HPO42- ions indicates its fast response characteristic. The ISE can be used over a period of three months with good reproducibility and selectivity. The manufacture process of the ISE is easy and inexpensive. It can be applied to quantitative analysis of phosphate in water. (C) 2016 The Electrochemical Society. All rights reserved.