Enhanced catalytic activity of platinum decorated silica nanocrystals in rapid reduction of organic dyes

Abstract

Pt decorated silica (Pt/SiO2) nanocrystals (NCs) were synthesized using a chemical route, and their activities were evaluated towards the reduction of Methylene Blue (MB), Rhodamine B (RhB) and p-Nitrophenol (PNP). X-ray diffraction (XRD) analysis confirmed cubic crystal structure of Pt NCs. The formation of monodispersed spherical SiO2 nanoparticles with an average particle size of ∼150 nm was confirmed by Field Emission Scanning Electron Microscopy and Transmission Electron Microscopy. The High Resolution TEM confirmed cubic crystal structure of Pt NCs having lattice fringes with interplaner spacing of ∼0.29 nm, corresponding to (111) plane. The catalytic activities of the Pt/SiO2 NCs towards MB, RhB and PNP were studied using UV-visible spectrophotometer. The Pt/SiO2 NCs showed excellent catalytic activity with pseudo first order rate constant values 0.016 s−1, 0.011 s−1, 0.006 s−1 for MB, RhB and PNP, respectively. The synthetic method used in the present work offers valuable insights for facile preparation of Pt/SiO2 NCs as an efficient and valuable catalyst for environmental remediation.

Keywords

• Pt/SiO2 NCs
• Catalytic activity
• Methylene blue
• Rhodamine B
• p-Nitrophenol