Comparison of Green Bio-Based Cerium/Alginate vs. Copper/Alginate Beads: Study of Vibrational And Thermal Properties Using Experimental And Theoretical Methods

Abstract Herein, bio-based alginate (Alg) containing-metal atom beads (M= Cu and Ce) were synthesized via an alginate cross-linking method, and studied using experimental techniques combined with theoretical simulations. Firstly, FTIR, TGA and SEM analyses were carried out to study the cross-linking structural features,, thermal stability, and surface morphology. Besides, density functional theory (DFT) methods were used to calculate global reactivity parameters such as HOMO-LUMO energy gaps (ΔEH-L), electronegativity (μ), hardness (η), and electrophilic and nucleophilic indicators using both gas and aqueous media ; the latter for the study of the complexation process. Results showed that Alg@Ce and Alg@Cu beads behave differently and as a function of the increasing temperature. This behaviour c was also predicted by the energy conformer differences between Alg@Ce and Alg@Cu, which were found out theoretically and explained with the combined study of the vibrational modes between the carboxylate group with either Cu or Ce. Overall, the reactivity of the Alg@Ce bead was higher than that of the Alg@Cu counterpart; results could be used as a cornerstone to transfer the materials here studied to a wider range of applications.