Facile modification of ITO electrodes with functional materials through catalytic grafting of N-hydroxysuccinimidyl-ester-functionalized methallylsilane

A facile method for the preparation of modified indium tin oxide (ITO) electrodes and their use in amperometric sensing of H2O2 are described. ITO surface was first derivatized by acid-catalyzed grafting of N-hydroxysuccinimidyl-ester-functionalized methallylsilane at room temperature, followed by immobilization of functional materials such as gold nanoparticle and thionine by amide coupling reaction. The modification process was monitored using contact angle, scanning electron microscopy and electrochemical measurements, which revealed the controllability and high efficiency of this modification method. Thionine-modified ITO electrode exhibited excellent electrocatalytic activity towards the reduction and amperometric determination of H2O2, demonstrating the potential of this modification strategy in electrocatalysis and amperometric sensing. Keywords: Indium tin oxide, Methallylsilane, Catalytic grafting, Gold nanoparticles, Thionine, H2O2