Highly sensitive and selective electrochemical sensing of Hg(II) at the nanoscale using novel nanosized cobalt phthalocyanine and PVA-TEOS as binder

Mercury has been recognized as one of the primary toxic environmental contaminants amongst all the heavy metal ions which pose a serious threat to the environment as well as the human race. Hence, time demands a convenient and affordable method for its detection. In view of this, we have synthesized a novel, nanosized 4-((5-phenyl-4H-1,2,4-triazol-3-yl)thio) cobalt(II)phthalocyanine (TACoPc) sensor material and confirmed it by spectroscopic techniques. Alongside, a novel poly(vinyl alcohol)-tetraethyl orthosilicate (PVA-TEOS) binder was coated on bare GCE and subjected for stability and conductivity performance in 1 M concentration of various electrolytes followed by its fabrication using TACoPc electroactive sensor material. Further, the detection of Hg(II) was carried out through cyclic voltammetry (CV), differential pulse voltammetry (DPV) and amperometric i-t curve. The fabricated TACoPc sensor electrode was found to have a good sensitivity of 7.460 µA nM⁻¹L⁻¹ and a limit of detection (LOD) of 0.47087 nM for Hg(II) was achieved in 0.1 M phosphate buffer of pH = 7.4 by DPV. The modified electrode exhibited high selectivity towards Hg(II) without any interference towards 10 different interfering ions at higher concentrations. The TACoPc sensor electrode possessed good stability and reproducibility. The present work expands the scope of electrochemical determination with better performance in the selective investigation of Hg(II).