Self-Assembly of Molybdophosphate on a Glassy Carbon Electrode Covalently Modified with Choline and Electrocatalytic Reduction of Iodate

摘要

Choline can be covalently grafted on glassy carbon electrodes using cyclic voltammetric method, forming a stable cationic monolayer-modified electrode (Ch/GCE). Keggin-type molybdophosphate anions, α-PMo12O403-, then were self-assembled on the Ch/GCE through electrostatic interactions for fabrication of an electrochemical sensor, which is denoted as α-PMo12/Ch/GCE. This two-layer modified electrode was carefully characterized by cyclic voltammetry and X-ray photoelectron spectroscopy. It was found that the sensor exhibits strong electrocatalytic activity and sensitivity toward the reduction of IO3-. The content of IO3- in a table salt was determined with satisfactory results. The sensor is promising as an electrochemical sensor for the detection of IO3-.