A promising electrochemical sensing platform based on a silver nanoparticles decorated copolymer for sensitive nitrite determination

Abstract

In this paper, we report a facile route to synthesize silver nanoparticles (Ag NPs) incorporated into a copolymer of methyl methacrylate (MMA) and 2-acrylamido-2-methylpropane sulfonic acid (AMPS) (abbreviated as P(MMA-co-AMPS)) and its application to construct an electrochemical nitrite (NO2-) sensor. The copolymer nano-composite material (Ag-P(MMA-co-AMPS) is characterized by means of transmission electron microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, UV-vis spectroscopy, X-ray powder diffraction methods, thermogravimetric analysis and electrochemical impedance spectroscopy. Further, Ag-P(MMA-co-AMPS) is used to prepare an electrochemical sensing platform (ESP) on a glassy carbon electrode (GC) surface. NO2- is electrocatalytically oxidized at the ESP (GC/Ag-P(MMA-co-AMPS), which leads to a sensitive determination of NO2-. The oxidation current of NO2- is linear to its concentration in the range of 1.0-100000.0 μM and the detection limit is found to be 0.2 μM with a sensitivity 104.6 μA mM-1 cm-2. The observed analytical parameters such as wide linear range, low detection limit, high sensitivity and short response time are comparable or superior to other previously reported NO2- sensors. Kinetic parameters are evaluated using cyclic voltammetry and chronoamperometry. Finally it is demonstrated that the proposed sensor can be used for the selective determination of NO 2- present in water samples and the results are quite promising. © 2014 The Royal Society of Chemistry.