Switchable voltammetric response of electrodes modified with a mesoporous silica thin film and a polyelectrolyte multilayer

Abstract

Simple modification techniques affecting surface properties in a switchable manner are key to the development of smart materials. Layer-by-layer assembly of oppositely charged polyelectrolytes (poly(diallyldimethylammonium chloride) and (poly(styrene sulfonate)) over an electrode modified with a mesoporous silica thin film makes a platform with alternating amplification and sieving electrochemical properties defined by the terminating polyelectrolyte layer. The mesoporous silica thin films were formed via sol–gel processing in the presence of a soft template (Electrochemically Assisted Self-Assembly). The electrochemical properties of the designed platforms were studied in the presence of positively charged (Ru(NH3)63+), neutral (FcMeOH), and negatively charged (Fe(CN)64-) redox probes. Additionally, we provide proof-of-concept studies in which our platforms are applied to the electroanalytical screening of ascorbic acid and dopamine.