Synthesis of Nano-Cobalt Metal Doped Carbon for Hydrogen-Phosphate Ion Sensor

Abstract

Nano Co-metal doped carbon powder could be prepared by a carbon-combustion method using large surface area carbon loaded with Co-nitrate. The Co-carbon thick-film sensor prepared by screen printing method showed relatively good response of potentiometric sensing to hydrogen-phosphate ion in the concentration range between 3.0×10^-4 M and 1.0×10^-2 M at pH=5 with high selectivity among the tested anions; NO₃^-, Cl^-, Br^-, HCO₃^-, and CH₃COO^-. The 90% response time of the sensor device was as short as about 3 min at room temperature.