Luminescent Cd(II) Fumarate Bridging 1D Coordination Polymer: Ultra-Trace Level Detection of Cu2+ in Aqueous Medium and Fabrication of Semiconducting Device

Abstract

In addressing the Sustainable Development Goals (SDGs) the UNDP has fixed 17 issues out of them clean water (SDG-6) and affordable energy (SDG-7) serve as decisive points towards sustenance of the society. Material chemistry plays a vital role to design new chemical compounds and exploring versatile activities towards the solution of pressing challenges. Copper, third abundant metal in human body following iron and zinc, is useful to monitor many metabolic processes. Exposure to high level Copper or its deficiency can cause various health issues. It is essential to determine quantity of Cu²⁺ in a wide range of consumables. A luminescent coordination polymer (LCP) of Cd²⁺(d¹⁰) as a metal node, fumaric acid (fuma²⁻) as a linker and tripod N-coordinated 4′-Chloro-2,2′,6′,2“-terpyridine (4-Cltpy) as end-capping ligand, {[Cd(fuma)₂(4-Cltpy)].(H₂O)}_n (CP1), has been used in this research for trace quantity detection of Cu²⁺ in aqueous solution (LOD: 0.0307 μM (Cu(II)) (WHO recommended toxicity limit of Cu(II) is 3.15 μM). The band gap of CP1 (experimental value by Tauc's plot, 3.56 eV and theoretically calculated band gap, 3.54 eV) directs to fabricate Schottky semiconducting device (ITO/CP1/Al) which determines electrical conductivity, 4.52×10⁻⁴ Sm⁻¹ at room temperature. Therefore, CP1 is a promising candidate as a conductive material and a sensor. Because of its dual purpose, CP1 may be very beneficial for device applications and a breakthrough in material science in near future.