SiO2 supported highly dispersed Pt atoms on LaNiO3 by reducing a perovskite-type oxide as the precursor and used for CO oxidation

Abstract A new facile method for preparing highly dispersed precious metal catalysts was proposed in this work. Highly dispersed Pt supported on LaNiO 3 /SiO 2 were prepared by using LaNi 1- x Pt x O 3 perovskite as precursors. The catalytic performances of CO oxidation over the prepared catalytsts were investigated. The structural features of the catalysts were characterized by N 2 adsorption-desorption, XRD, H 2 -TPR, TEM, EXAFS, CO-TPD and O 2 -TPD techniques. The result indicated that nanocrystalline of LaNi 1- x Pt x O 3 was supported on SiO 2 . Reducing LaNi 1- x Pt x O 3 /SiO 2 could make Pt from the interior of the perovskite crystal lattice onto the surface and then form highly dispersed Pt on the support of LaNiO 3 /SiO 2 . As the platinum content was 0.5% or less, platinum atoms could distribute highly even maybe in single atoms. The catalytic test revealed that LaNi 0.95 Pt 0.05 O 3 /SiO 2 exhibited a significant activity and stability for CO oxidation, as well as excellent performance in the presence of both 15 vol.% H 2 O and 12.5 vol.% CO 2 . It has been demonstrated that the highly dispersed Pt, the easy reducibility, and sufficient surface oxygen species were responsible for the high catalytic activity of LaNi 0.95 Pt 0.05 O 3 /SiO 2 catalyst.