Cu(II)-carboxymethyl chitosan-silane schiff base complex grafted on nano silica: Structural evolution, antibacterial performance and dye degradation ability

Abstract

O-Carboxymethyl chitosan (OCMC) Schiff’s base was utilized for a new class of organic-inorganic hybrid material by grafting it on nano-silica-silane and further metallated with Cu (II). Here (3-Aminopropyl) triethoxysilane (APTES) was used as a linker and 2-hydroxy-1-naphthaldehyde (HN) for Schiff’s base formation. The hybrid was characterized by FTIR, TGA, powder XRD, SEM, CHN, DLS, ICP-AES, diffuse reflectance UV–vis and EDX spectroscopic techniques. Magnetization measurements were carried out by VSM at room temperature. This study explored the possible synergic effect of unique properties of carboxymethyl chitosan, Schiff’s base Cu (II) complex and nano-silica towards antibacterial activity and in dye degradation studies. The antibacterial performance of nano-hybrid material was examined against both Gram-positive (Escherichia coli) and Gram-negative (Bacillus subtilis) bacteria. The catalytic activity of the hybrid was tested for degradation of reactive black 5 (RB5) through advanced oxidation processes using H2O2 as oxidant. The results show a high dye degradation efficiency of 93% in 130min by the hybrid catalyst with reusability. As per published reports, Chitosan-Schiff’s bases show strong antimicrobial activity and their Cu complexes exhibit good catalytic and anticancer activities. Therefore, it is expected that the new organic-inorganic hybrid would be highly applicable in environmental as well as biomedical fields.