Phytochemicals mediated synthesis of multifunctional Ag-Au-TiO2 heterostructure for photocatalytic and antimicrobial applications

In this study, Ag-Au bimetallic composite type nanoparticles (similar to 13 nm) were prepared in aqueous media using Aegle marmelos leaf extract. Upon etching with ammonia solution, the formed similar to 13 nm particles were reduced to similar to 5 nm spherical alloy type Ag-Au with higher Au content (similar to 82.0%). In addition, with Tetrabutyl orthotitanate introduction in the same reaction media, Ag-Au-TiO2 heterostructures (similar to 9 nm) were obtained. The synthesized nanoparticles of various types were analyzed by UV-Vis. and photoluminescence (PL) spectroscopy, HR-TEM, and FTIR techniques. It was found that among the synthesized particles, Ag-Au-TiO2 heterostructures displayed promising PL properties, superior photocatalytic activity towards SDBS degradation, and antimicrobial activity against the studied bacterium, Escherichia coli. The multifunctionality of these particles may be useful for many industrial applications such as catalysis to waste water treatment. (C) 2017 Elsevier Ltd. All rights reserved.