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

A new facile method for preparing highly dispersed precious metal catalysts was proposed in this work. Highly dispersed N supported on LaNiO3/SiO2 were prepared by using LaNi1-xPtxO3 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 LaNi1-xPtxO3 was supported on SiO2. Reducing LaNi1-xPtxO3/SiO2 could make N from the interior of the perovskite crystal lattice onto the surface and then form highly dispersed Pt on the support of LaNiO3/SiO2. As the platinum content was 0.5% or less, platinum atoms could distribute highly even maybe in single atoms. The catalytic test revealed that LaNi0.95Pt0.05O3/SiO2 exhibited a significant activity and stability for CO oxidation, as well as excellent performance in the presence of both 15 vol.% H2O and 12.5 vol.% CO2. It has been demonstrated that the highly dispersed N, the easy reducibility, and sufficient surface oxygen species were responsible for the high catalytic activity of LaNi0.95Pt0.05O3/SiO2 catalyst.