Exploring Polyaniline Nanofilaments for Enhanced Optical Recognition of Lead in Water: An Integrated Approach of Experimental and Theoretical Studies

Abstract

In this study, the behavior of lead adsorbed onto polyaniline composite was examined theoretically with the DFT method and experimentally using spectrophotometry. The synthesis and characterization of polyaniline nanofilaments (PANI) were executed. Density functional theory and Becke's three-parameter exchange functional approach were employed for quantum mechanical calculations of geometry and energy. The 6.311G** basis set and the Lee-Yang-Parr correlation functional method (B3LYP/DFT) were used in a water solution environment to complement the experimental data. Experimental results were visualized using 3D molecular electrostatic potential maps (MEP), which aided in the determination and explanation of various properties, including mean polarizability, total static dipole moment, anisotropy of polarizability, and mean first-order hyperpolarizability. The findings indicate that Pb-PANI-EB shows promise as a potential material for non-linear optical (NLO) applications. PANI demonstrate efficacy as a sensor capable of detecting Pb concentrations as low as 0.05 ppm. These results justify further exploration of the use of PANI in the development of a fast, economical, robust, and highly sensitive lead (Pb) sensor.