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We report on the development of a highly sensitive electrochemical sensor for the rapid detection of dopamine and acetaminophen molecules based on barium titanate nanocubes deposited on a glassy carbon electrode. The as-synthesized barium titanate nanocubes were characterized using X-ray diffraction measurements, field emission scanning electron microscopy, and UV–vis diffuse reflectance spectroscopy. The electrochemical performances of the as synthesised nanomaterials were investigated by cyclic voltammetry differential pulse voltammetry. A linear response was exhibited by the modified electrode for both dopamine, and acetaminophen in the range 10-100 μM, and the detection limit (S/N=3) was calculated to be 0.35 μM, 0.23 μM respectively. Under the optimised conditions, highly stable, sensitive, selective, and reproducible performances were exhibited by the electrochemical sensor. Furthermore, the as developed sensor also showed acceptable recoveries for the analysis of real samples.

The development of ingenious technologies for the purification of wastewater containing highly toxic organic compounds is of high importance in the current research. The application of noble metal nanocatalysts in the presence of sodium borohydride (NaBH 4 ) for the removal of these toxic compounds through chemical reduction method have become an accepted approach in the recent years. The present work reports on the development of a convenient approach to fabricate free standing, robust, and flexible reduced graphene oxide -silver/ polyvinyl alcohol (rGOÀ Ag/PVA) nanocomposite film. The morphological and structural characterizations of the as developed film have been carried out using SEM, TEM, EDAX, Raman, BET, and TGA. The performance of as developed rGOÀ Ag/PVA nanocomposite film is tested as heterogeneous catalyst in the reduction reaction of 4-Nitrophenol and reduction of Methyl Orange dye. The nanocomposite filmbased catalyst exhibited excellent catalytic performances as well as excellent stability in the reduction of toxic organic compounds in wastewater.

Gum Arabic stabilized silver nanoparticles were successfully synthesized by a one step green synthesis method. The as-prepared nanoparticles were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy, tunneling electron microscopy (TEM), and UV-Vis spectroscopy. XRD data confirmed that the synthesized Ag nanoparticles were face-centred cubic and the crystallite size was calculated to be around 5 nm. TEM imaging confirmed the successful synthesis of monodispersed spherical nanoparticles with the particle size in the range 10-20 nm. Cyclic voltammetry experiments revealed the outstanding electrochemical response and electrocatalytic behaviour of GA-Ag NPs for the sensing of hydrogen peroxide. Based on the cyclic voltammetry, amperometric, and differential pulse voltammetric experiments, it was concluded that strong oxidizing agent H2O2 undergoes through reduction process at the surface of GA-Ag NPs/GCE. Excellent electrocatalytic behaviour of the GA-Ag NPs was exhibited for sensing of glucose also. The limit of detection as calculated from DPV experiments were 0.242 and 0.205 M for H2O2 and glucose, respectively. The reported electrochemical sensor has numerous advantages such as simple and green synthesis method, extremely high sensitivity, stability and reproducibility, and extremely good response.