Catalytic reduction and antibacterial study of magnetic organo-montmorillonite@CuNPs: Effect of the surfactant chain length

The present study concerns the preparation of sodium and organo-modified montmorillonite (Na-MMT, C₁₄-MMT, C₁₆-MMT and C₁₈-MMT), these materials were used as matrix in which the Fe₃O₄ and CuNPs were dispersed by ultrasonic treatments. The resulting nanocomposites were characterized XRD, FTIR, TGA, Zeta potential, UV–Vis, SEM, EDS, TEM, SAED and nitrogen adsorption-desorption to evaluate their structural, thermal, morphological, and textural properties. The results showed that intercalation of alkylammonium chain improved the nanoparticles dispersity and allowed to obtain a smaller size. The obtained nanocomposites were evaluated in the catalytic reduction of methylene blue and orange G in simple and binary system and in the presence of NaBH₄ as reducing agent. The antibacterial potential of these materials was evaluated against two gram-positive and two gram-negative bacteria. The effect of surfactant chains length on the physicochemical, catalytic and antibacterial properties of these nanocomposites were investigated and strongly highlighted. The C₁₈-MMT@Fe₃O₄@CuNPs “C4” showed the best catalytic activity and antimicrobial activity with a total degradation in 04 min and 03 min against MB and OG respectively and an inhibition zone of 19, 21, 22 and 21 mm against E. coli, S. typhimurium, L. monocytogenes and S. aureus respectively. The C4 nanocomposite was compared to several catalysts reported in the literature. Finally, the materials were reused during five successive cycles and showed excellent potential and no noticeable loss of efficiency.