Several nanocomposites of tin oxide with CuS, SnS or Cu@SnS were prepared and used to modify carbon paste electrodes (CPEs). The structure and morphology of the materials were studied by XRD and SEM techniques. Cyclic voltammetry and electrochemical impedance spectroscopy were applied to investigate their electrochemical properties. The modified CPEs exhibit superior voltammetric response to paracetamol (PAT) and hydroquinone (HQ) (when compared to a bare CPE) in terms of onset oxidation potential and current density. The CPE modified with SnO2/SnS was applied to voltammetric determination of PAT (at a working potential of 0.55 V versus Ag/AgCl and with a 0.06 μM detection limit), and of HQ (at 0.39 V versus Ag/AgCl with a 0.2 μM detection limit). The voltammetric responses were linear in the range from 1.0 to 36 μM for PAT and from 1.0 to 85 μM for HQ. Graphical abstract Carbon paste electrodes were modified with several new tin oxide and sulfidic nanocomposites and then exhibit superior properties in terms of detection of paracetamol and hydroquinone.
Keywords: Cyclic voltammetry; Differential pulse voltammetry; Electrocatalytic oxidation; Electrode modification; Microstructural analysis; Nanomaterial; Nanoparticles; Pharmaceutical analysis; Tin oxide.