Ternary hybrid Au@Pt–TiO2 nanocomposites: Highly thermally stable photocatalyst with highly efficient visible-light photocatalytic activity

Abstract

In this research paper, ternary hybrid Au@Pt–TiO2 nanocomposites (NCs) were synthesized as a new class of nanomaterial. The ternary nanocomposites (TNCs) were obtained via the new one-pot solvothermal chemical process. The experimental protocol involves the use of only Au(III) and Pt(IV) precursors in dimethyl sulfoxide (DMSO) as solvent. No reducing agent, surfactants or ligands are needed in this process, which makes it a simple low-cost wet chemical procedure. The prepared TNCs exhibited high crystallinity and high thermal stability with an average size of about 20 nm. Full characterization was performed including X-ray powder diffraction (XRD), high-resolution microscopy (HRTEM), X-ray fluorescence (XRF) and X-ray photoelectron spectroscopy (XPS) to confirm the presence of both Au and Pt nanoparticles (NPs) on the TiO2 surface and, therefore, the formation of these hybrid TNCs. All data are coherent and confirm well the formation of this ternary nano-system. The synthesized hybrid TNCs exhibit an interesting and motivating optical response in both the ultraviolet and visible regions. To study the performance of the TNCs their photocatalytic activity was analyzed. As expected, the TNCs exhibit a higher photocatalytic performance compared to bare TiO2 and to monometallic Au–TiO2 and Pt–TiO2.

Keywords

• Nanocomposites
• Photocatalytic activity
• TiO2
• Noble metal
• Solvothermal process