Synthesis and characterization of MWCNT/TiO2/Au nanocomposite for photocatalytic and antimicrobial activity.

A novel combination of titanium oxide (TiO2)/gold (Au)/multiwalled carbon nanotubes (MWCNTs) nanocomposite (NC) was synthesised by sol- gel method. MWCNT functionalisation by modified Hummers method. TiO2/Au nanoparticles (NPs) were synthesised by biological method using Terminalia chebula bark extract. MWCNT/TiO2/Au NC samples were characterised by X-ray diffraction, ultraviolet-visible-diffuse reflectance spectra, microRaman, scanning electron microscopy and high-resolution-transmission electron microscopy analyses. The photocatalytic performance of the obtained for NC toward the decomposition of congo-red and the antimicrobial activity for inhibition of Gram positive (Bacillus subtilis, Streptococcus pneumonia and Staphylococcus aureus), Gram negative (Shigella dysenderiae, Proteus vulgaris and Klebsiella pneumonia) and fungal strains have been evaluated and the results are compared with positive control ampicillin. The metal and metal-oxide NPs have a lower sorption capacity. The herbicidal bond to the tested CNTs by the combination of electron donor-acceptor interactions and hydrogen bonds. In particular, the dispersion of NC and control of sodium borohydride, it has more efficient effect on the photodegradation and antibacterial activity of positive control of ampicillin. The NC material has exhibited maximum photodegradation and antibacterial activity results of zone of inhibition when compared with control samples.