Preparation of hollow Ag/Pt heterostructures on TiO2 nanowires and their catalytic properties

• TiO2 NW@hollow Ag/Pt heterostructure catalyst was successfully prepared.
• The catalyst provides accessible interfaces and high surface-to-volume ratio.
• The hollow Ag/Pt nanostructures supply defects, vacancies and boundaries.
• The catalyst shows enhanced catalytic activity and excellent reusability.

A novel titanate (TiO2) nanowire (NW)@hollow silver (Ag)/platinum (Pt) heterostructure was fabricated by means of a simple wet chemical method. Briefly, Ag nanoparticles with ∼20 nm in diameter were grown onto TiO2 nanowires, subsequently PtO shells with ∼1 to 4 nm in thickness were deposited upon the Ag nanoparticles to form TiO2–NW@Ag–NP@PtO nanostructures. The hollow Ag-/PtOx nanostructures were achieved from Ag–NP@PtO nanostructures by outward diffusion of Ag elements from Ag–NP core to PtO shell via H2O2 treatment. Finally, hollow Ag/Pt heterostructures with diameter of approximately 20 nm were synthesized by reduction of the hollow Ag-/PtOx nanostructures. Given the accessible interfaces of bimetallic Ag/Pt shell, the catalytic efficiency of the TiO2 NW@hollow Ag/Pt heterostructures was significantly enhanced, which was confirmed by the hydrogenation of p-nitrophenol into p-aminophenol with NaBH4 as reducing agent in aqueous phase. The conversion rate of p-nitrophenol was yielded as high as ∼95% for 9 min under ambient atmosphere and room temperature.

Figure optionsDownload as PowerPoint slide