Crystal structure of N′-[(E)-(2-hydroxynaphthalen-1-yl) methylidene] benzenesulfonohydrazide (HNMBSH) and its application as Pb2+ ion sensor by its fabrication onto glassy carbon electrode

Abstract

Lead (Pb) is one of the ten most public health concern chemicals identified by World health organization (WHO). It is mostly present in Pb2+ form and enlisted in one of the most toxic having metals having capability to cause tumour. An excellent sensor, N′-[(E)-(2-hydroxynaphthalen-1-yl) methylidene] benzenesulfonohydrazide (HNMBSH) for Pb2+, is synthesized by following a simple condensation approach where 2-hydroxynaphthalene and benzene sulfonylhydrazide were reacted equi-molar in ethanol. The title compound was collected in very good yield and crystallized in ethanol. The structure was determined by 1H NMR, 13C NMR, UV/vis, FT-IR and single crystal X-ray diffraction. HNMBSH was fabricated on flat-glassy carbon electrode (GCE) with nafion i.e.; a conducting binder in phosphate buffer phase and used as Pb2+ short response time sensor. The fabricated HNMBSH/Nafion/GCE sensor is exhibited higher sensitivity, large-dynamic concentration ranges, long-term stability, and improved electrochemical performances towards Pb2+ ions. The calibration plot is linear over the large Pb2+ concentration ranges (0.1nM to 1.0mM). The sensitivity, detection limit and limit of quantification of this newly proposed method are found to be ∼3.956µAmM−1cm−2, ∼0.024nM (signal-to-noise ratio, at a SNR of 3) and 0.08nM respectively. This novel effort is initiated a well-organize way of efficient HNMBSH/Nafion/GCE sensor development with conducting binder deposited GCE for toxic heavy cationic pollutants in environmental and health-care fields in broad scales. Therefore, the HNMBSH/Nafion/GCE sensor offers a cost effective organic ligand that can be considered as a viable alternative for effectively detecting and removing hazardous and carcinogenic Pb2+ from real water samples.