Modeling and experimental insight into the electronic and structural properties of Sodium alginate/Polypyrrole/Titanium dioxide nanocomposites

Abstract The creation of functional materials which enable adjustable electronic properties was fundamental to the development of electronic sensors and biomedical applications. The research assesses a ternary nanocomposite system which combines sodium alginate (SA) with polypyrrole (PPy) and titanium dioxide (TiO 2 ) through dual methods of computational simulation and experimental testing. The researchers used Density Functional Theory (DFT) simulations at the B3LYP/6-31G(d, p) level to study how molecules interact with each other and how their electronic structures behave. The research demonstrates that the SA/PPy/TiO 2 composite material exhibits better electronic performance because it shows both a smaller energy gap and a smaller total dipole moment. The global reactivity indices which include ionization energy, chemical hardness, and the HOMO-LUMO gap reveal a synergistic effect which enhances charge transfer according to Density of States (DOS) measurements and Quantum Theory of Atoms in Molecules (QTAIM) results. The researchers used FTIR and UV-Vis spectroscopy to confirm that SA/TiO 2 composite films matched theoretical predictions at a high accuracy. The B3LYP/6-31G(d, p) level shows that it successfully detects a smaller HOMO–LUMO gap which demonstrates that the studied composites exhibit greater chemical reactivity and better internal charge transfer and higher electrical conductivity.