Effect of silver encapsulation on the local structure of titanosilicate ETS-10

Kalay, Yunus Eren
Özkar, Saim
Akata, Burcu
Silver(0) nanoparticles stabilized by titanosilicate (ETS-10) framework were synthesized by following a simple two step procedure involving the incorporation of silver(I) (Ag+) ions into ETS-10 matrix via ion-exchange with extra framework Na+ and K+ cations followed by their reduction with sodium borohydride (NaBH4) in aqueous medium all at room temperature. Silver(0) nanoparticles dispersed in the ETS-10 matrix were collected as gray powders and characterized by using advanced analytical methods including ICP-OES, P-XRD, XPS, FE-SEM, TEM, HR-TEM, DR-UV-vis, Raman spectroscopies and N-2 adsorption-desorption technique. Overall result shows the formation of silver(0) nanoparticles dispersed within the framework of ETS-10 without causing alteration in ETS-10 lattice and mesopore formation. The changes in the local titanate (TiO32-) structure of ETS-10 resulting from the incorporation of silver(I) ions and formation of silver(0) nanoparticles within the titanosilicate (xTiO(2) (1 - x)SiO2) framework were extensively studied on silver(I)-exchanged and silver(0) nanoparticles containing samples, separately. Although maintaining of structural integrity of host material had been monitored for silver(I)-ETS-10, detailed Raman analyses of silver(0)-ETS-10 samples showed significant changes in the titanate quantum wires of ETS-10 framework depending on the silver loading. Total collapse of these units was observed in the silver(0)-ETS-10 samples with high silver loading (15 wt.% silver(I)). Moreover, the catalytic application of silver(0)-ETS-10 was demonstrated in the aerobic oxidation of diphenyl carbinol to benzophenone, which showed that silver(0)-ETS-10 is a highly active and selective catalyst in this reaction. Additionally, they were found to be highly stable catalyst for this transformation.

Citation Formats
S. GALIOGLU, M. ZAHMAKIRAN, Y. E. Kalay, S. Özkar, and B. Akata, “Effect of silver encapsulation on the local structure of titanosilicate ETS-10,” MICROPOROUS AND MESOPOROUS MATERIALS, vol. 159, pp. 1–8, 2012, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/42922.