Photocatalytic degradation of methylene blue dye using plasmonic nanoparticles deposited TiO2 nanorod based hybrids

Abstract

Titanium dioxide (TiO2) based hybrid nanostructures possess a lot of ability for photocatalytic applications. Combining TiO2 nanostructures with plasmonic nanoparticles (PMNPs) for the formation of hybrids increases its photocatalytic activity via surface enhanced raman scattering (SERS) effect. In reference to that, current work reports the PMNPs deposited TiO2 nanorods (TONRs) for enhanced photocatalytic activity. PMNPs of gold (Au) and silver (Ag) are deposited over TONRs for the formation of PMNPs-TONRs hybrids. Scanning electron microscopy confirmed the presence of Ag and Au PMNPs. The micro-Raman studies of PMNPs-TONRs hybrids exhibit the increased Eg mode owing to surface enhanced raman scattering (SERS) effect. The enrichment in hybrids is associated to the interaction of PMNPs and TONRs. Furthermore, the decoration of Au PMNPs on TONRs have been found efficient to modify the Schottky barrier. The modified hybrid nanostructures are further studied for electrochemical measurement. It is analyzed that higher electrical conductivity is present in Au decorated TONRs, which facilitates the transport of charge carriers. PMNPs-TONRs hybrids are being investigated further for photocatalytic applications by the degradation of methylene blue dye. It is observed that the Au PMNPs based hybrids have a higher photocatalytic activity with the reduction of 90% in comparison to Ag based hybrids with 72% reduction. It may be due to stronger Schottky effect and SERS effect with the presence of Au nanoparticles.