Development Of Nanomaterial Based Composite System For Removal Of Heavy Metals From Wastewater

Abstract

Heavy metals in wastewater and natural water bodies occur at trace levels but are highly toxic even in minute concentrations. Although nanomaterials provide excellent reactivity for contaminant removal, their direct use in water treatment raises concerns of nanoparticle leaching and nano-toxicity. Therefore, this study focuses on the synthesis, characterization, and immobilization of metallic nanoparticles onto suitable substrates, and their application in heavy-metal sensing and removal. Silver (Ag), copper (Cu), and nickel (Ni) nanoparticles were synthesised via chemical reduction and characterized using FTIR, XRD, and TEM, confirming average particle sizes of 50 nm, 20 nm, and 10 nm, respectively. Their interaction with Rhodamine-B dye revealed significant tuning of photoluminescence properties, including a notable blue shift from 700 nm to 585 nm and enhanced emission intensity due to uniform dye dispersion on nanoparticle surfaces. Photoluminescence quenching studies enabled the detection of Pb(II), Cr(VI), and Cd(II) ions, with detection limits of 5.71 mg/L, 2.63 mg/L, and 3.87 mg/L, respectively, demonstrating strong potential for heavy-metal sensing.