Enhanced Electrochemical Performance of Copper(II) Metal Organic Framework-Ternary Quantum Dots Composite towards the Detection of Bisphenol A

Abstract

Ternary quantum dot metal organic framework (MOFs) composite sensor formulated as (ZnInSe₂@[Cu(2-HNA)₂(H₂O)]) with an enhanced electrochemical performance was synthesized from a copper(II) metal-organic framework complex ([Cu(2-HNA)₂(H₂O)]) and ZnInSe₂ ternary quantum dot (TQDs). The compounds were characterized by Fourier transform infrared spectroscopy, Ultraviolet-Visible spectroscopy, transmission electron microscopy, scanning electron microscopy, single crystal X-ray crystallography, and photoluminescence. Molecular structure of the copper(II) complex revealed a distorted square pyramidal geometry with two molecules of 2-hydroxy-1-naphthaldedyde at the basal planes as bidentate chelating ligands with a coordinated water molecule at the apical position. TEM micrographs revealed monodispersed composite with an average particle size of 3.2 nm. The composite and its precursors were used as ectrochemical sensor for the detection of bisphenol A, using cyclic voltammetry, differential pulse voltammetry, and electrochemical impedance spectroscopy. The composite modified on a gold electrode exhibited enhanced electrochemical performance in comparison to those of the MOFs and TQDs. The reaction process at the surface of the modified electrode with the composite is diffusion controlled with a limit of detection, and limit of quantitation of 4.70 nM and 14.26 nM over a concentration range of 10–50 nM (S/N=3). The gold modified composite electrode is stable and could serve as a model for the development of electrochemical sensor to determine BPA.