Improved antimicrobial efficacy and photocatalytic performance of gold decorated titanium dioxide nanohybrid

Abstract

The present work deals with the improved antimicrobial and photocatalytic efficacy of gold (Au) decorated onto titanium dioxide (TiO2) nanoparticles (NPs). For the synthesis, the TiO2 NPs were first prepared by the hydrothermal method, followed by the introduction of AuNPs via seed growth method to generate Au@TiO2 NPs. The various physical characterization techniques like powder XRD, UV–vis, FTIR, DLS, zeta potential, and HRTEM analysis were applied for the typical understanding of crystal, optical, functional, surface, and morphological properties of Au@TiO2 nanohybrids. Besides, the antimicrobial susceptibility testing of Au@TiO2 nanohybrids against Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Candida albicans (C. albicans) bring out the containment efficacy as compared to that of TiO2 and AuNPs. Further studies on the photocatalytic effect of Au@TiO2 nanohybrids towards the degradation of methylene blue (MB) dye attributed significantly enhanced catalytic activity. The enhanced activity of core-shell Au@TiO2 NPs may be due to the improved light-harvesting efficiency based on the resonance of Au ameliorating improved catalytic activity to TiO2. This doping process with the transition metals might enhance the photocatalytic efficacy which finds its implications in the biomedical as well as for the bioremediation processes.