Cobalt (II) tetra methyl-quinoline oxy bridged phthalocyanine carbon nano particles modified glassy carbon electrode for sensing nitrite: A voltammetric study

The present work describe the synthesis of 4-[(4-methylquinolin-8-yl) oxy] benzene-1, 2-dicarbonitrile, Cobalt (II) tetra methyl-quinoline oxy bridged phthalocyanine (CoTM-QOPc) and their characterization by FT-TR, UV–Visible, Mass spectroscopy, PXRD, TGA and electrochemistry. The sensing of nitrite is done on Cobalt (II) tetra methyl-quinoline oxy bridged phthalocyanine modified glassy carbon electrode (CoTM-QOPc/GCE) in linear range of (CV 0.3–120, CA 0.2–170 μmolL-1), lower detection limit of (CV 0.1, CA 0.06 μmolL−1) and sensitivity of (CV 0.765, CA 1.204 μAμM−1cm−2). For better voltammetric study CoTM-QOPc was mixed with carbon nano particles (CNP) which increase the surface area of glassy carbon electrode, therefore sensing of nitrite has studied on CoTM-QOPc/CNP/GCE in linear range of (CV 0.2–200, DPV 0.2–225, CA 0.1–350 μmolL-1), lower detection limit of (CV 0.06, DPV 0.06, CA 0.033 μmolL−1) and sensitivity of (CV 2.298, DPV 1.031, CA 1.237 μAμM−1cm−2). The composite electrode shows enhanced electrocatalytic behaviour than modified electrode with Pc alone for the oxidation of nitrite. The fabricated sensor CoTM-QOPc/CNP/GCE shows high selectivity even in the presence of excess of interfering ions such as Ascorbic acid (AA), Carbonate (CO32-), urea, phosphate (PO43-) and glucose. [Display omitted] •Synthesised Cobalt (II) tetra methyl-quinoline oxy bridged phthalocyanine and characterized.•Modified the electrode surface with synthesised phthalocyanine and carbon nano particle.•Modified electrode shows excellent voltammetric response for nitrite oxidation with good linearity and LOD.•The method is easy to handle, reproducible and sensitive.