Developing an Electrochemical Sensor Based on Modified Siliceous Mesocellular Foam for Efficient and Easy Monitoring of Cadmium Ions

Abstract

In response to a mandatory demand to introduce sensitive technique to measure cadmium ion in ultra-trace concentration, an electrochemical sensor by applying modified siliceous mesocellular foam (S-MCF) with diphenylthiocarbazone as electrode material is developed. Several instrumental analysis including Fourier transform infrared spectrometry, nitrogen adsorption-desorption examination, scanning electron microscopy, thermal evaluation and elemental analysis were applied to characterize the prepared electrode material. In the work, the prepared electrode with introduced mesoporous material is conjugated with differential pulse anodic stripping voltammetry (DP-ASV) for ultra-trace measurement of Cd2+ ions. Cadmium ions interact strongly with active sites of diphenylthiocarbazone and a negative potential (-0.9 V) was applied to reduce these ions. Based on the specific characteristic of the electrochemical sensor, this electrode material was applied to pre-concentrate target ions on the modified electrode by the prepared mesoporous material. In order to measure Cd2+ at ultra-trace concentrations, differential pulse-ASV was utilized to oxidize the reduced Cd ions. Two dynamic linear range (DLR) for measurement of cadmium ions at ultra-trace concentrations were seen within ranges of 0.01 to 1.0 nmolL@1 (with sensitivity of 13.23 μA/nmolL@1) and 1.0 nmolL@1 to 10.0 nmolL@1 (with sensitivity of 0.23 μA/nmolL@1). The method detection limit (MDL) of 2.5 pmol L@1 was acquired.