A Potentiometric Sensor for Cd²⁺ Based on Carbon Nanotube Paste Electrode Constructed from Room Temperature Ionic Liquid, Ionophore and Silica Nanoparticles

A novel and effective potentiometric sensor for the rapid determination of Cd 2+ based on carbon paste electrode consisting of the room temperature ionic liquid 1‐butyl‐3‐methylimidazolium hexafluorophosphate, multiwalled carbon nanotubes, silica nanoparticles and ionophore was constructed. The prepared composite has a low potential drift, high selectivity and fast response time, which leads to a more stable potential signal. A linear dynamic range of 4.50×10 −9 –1.00×10 −1 mol L −1 with a detection limit of 2.00×10 −9 mol L −1 was obtained. The modified electrode was successfully applied to the accurate determination of trace amounts of Cd 2+ in environmental and biological samples.