Catalysis of Decomposition of H2O2 by Zeolite-Y Encapsulated in Trp-M(II)-His Ternary Complexes

The novel ternary or complex of three components with natural amino acids and transition metal ions encapsulated in Na-Y zeolite are catalytically active. Very few reports on catalysis of ternary complexes encapsulated in Zeolite framework are reported in literature. These nanocavity zeolite complexes have advantages, such as improved stability, selectivity, and catalytic activity due to confined environment of the zeolite. Hence, studies are carried out on the synthesis, characterization, and catalytic activity of nanocavity Na-Y-zeolite encapsulated M(II) (M = Co, Ni, Cu, Zn) complexes of Tryptophan and Histidine. These complexes are prepared by metal ion exchange followed by flexible ligand method. To validate the complex's encapsulation, its composition, structure and geometry, spectroscopic analysis like XRD, SEM, EDX, ESR, UV, and FTIR are applied. The creation of complexes in the voids without changing the structure of the Zeolite framework is indicated by the analysis of complexes by XRD studies. Scanning electron microscopy reveals the absence of any non-extraneous species. The geometry around the metal ions is predicted based on UV, FTIR, and ESR spectroscopy, whereas the composition is confirmed from EDX data. Further, these encapsulated ternary transition metal complexes were catalytically active in the decomposition of H2O2. When compared to Zn(II) enclosed complexes, the results showed that Cobalt(II), Copper(II), and Nickel(II) encapsulated ternary complexes were more active in H2O2 decomposition.