Electrochemical Detection of Nitrite Using an Asymmetrically Substituted Cobalt Phthalocyanine Conjugated to Metal Tungstate Nanoparticles

Abstract

This paper explores the synthesis and characterisation of an asymmetrical Co phthalocyanine (CoPc), and its covalent linking to two tungsten nanoparticles: bismuth tungsten oxide (Bi2WO6) and nickel tungsten oxide (NiWO4). The nanoparticles were also mixed with the CoPc. The CoPc, nanoparticles and their respective conjugates were used as electrocatalysts in the electrochemical detection of nitrite. The electrocatalysts studied in this work had sensitivities ranging from 3–133 μA/mM while the limits of detection (LoDs) ranged between 0.063 μM and 1.7 μM. Bi2WO6 and its conjugate exhibited better LoD than corresponding NiWO4 and conjugate.

Understanding the factors governing the water oxidation reaction pathway of mononuclear and binuclear cobalt phthalocyanine catalysts

“…Specically, the binuclear metal sites are 8 atoms apart from each other in bi-CoPc. The structures of both molecules were veried clearly by UV-vis 31 and FT-IR spectra 32,33 (Fig. S1a and b †).…”

Effect of detonation nanodiamonds on the electrocatalytic activity of asymmetric cobalt phthalocyanine: Covalent versus non‐covalent linking

“…The CoPc employed in this work is asymmetric. We have shown that asymmetry improves electrocatalytic activity of MPcs [12][13][14]. The asymmetrical CoPc is linked to detonation nanodiamonds (DNDs) covalently (CoPc@DNDs) or via π-π stacking (CoPc-DNDs(ππ)) for electrocatalytic oxidation of hydrazine as a test analyte.…”