Bio-inspired perylene diimide coated super paramagnetic nanoparticles for the effective and efficient removal of lead(ii) from aqueous medium

Abstract

Instability in water, the complexity of separation of the toxic substances produced and reusability issues for the reported materials used for the decontamination of lead from water are the hindrances that have caught the attention of the modern scientific community over the last few decades, resulting in the creation of an important field of research, the purification of heavy metals from water. Here, we unveil a unique ensemble, the perylene diimide coated magnetic nanoparticle, which is a conglomerate of ultra-photo stable perylene diimide [PDI] functionalized with biocompatible amino acid (levodopa) i.e. l–3, 4-dihydroxyphenylalanine (L-DOPA) capping the superparamagnetic Fe₃O₄ nanoparticle core, for the removal of lead from contaminated water. The nanomaterial has a very simple magnetic mechanism to remove lead from water involving chelation between the lead and the L-DOPA of PDI with an exceptionally high efficiency. The characterization of the nanomaterial was substantiated by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) analysis, high-resolution transmission electron microscopy (HR-TEM) and a physical property measurement system (PPMS). All of the materials (PDI, Fe₃O₄) are low in cost, nontoxic, and can be easily synthesized with an outstanding adsorption capacity of 1407.5 mg g⁻¹ and a K_d value of 1.14 × 10⁶ mL g⁻¹. This material can effectively reduce the Pb(II) concentration from 4000 to 7 ppb, well below the acceptable limit for drinking water standards and can effectively perform at a low pH level with a 99.97% efficiency. This amazing doughnut-shaped duo of PDI and Fe₃O₄ nanoparticle will make a significant contribution to the field of lead removal from water.