Amino-polysiloxane hybrid materials as carbon composite electrodes for potentiometric detection of anions

Abstract

Hybrid organic–inorganic polysiloxane materials functionalised with amino groups have been prepared and studied as active phases of potentiometric sensors for anion detection. The aminopolysiloxane matrix is obtained via sol–gel using 3-(trimethoxysilyl)propyl methacrylate (MAPTS) and N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (AETAPTS) as alkoxysilane precursors and allowing the amino groups to act as basic catalysts for the hydrolysis and polycondensation processes at room temperature. Graphite powder was added during the synthesis process in order to obtain electronically conductive composites for the preparation of the electrochemical sensors. Acid–base properties of the amino groups in the electrode surface allow the sensors to be applied in the electrochemical detection of several anions in aqueous solution. These sensors exhibit a long-time stability, robustness and a suitable electroanalytical performance in the potentiometric detection of anions in solution.