Background: Deposition of palladium nanoparticles from colloidal
solution on various supports produces palladium catalysts with a predetermined size
and concentration of the palladium nanoparticles, which allows to study the
nanoparticle size effects and support influence on palladium catalytic properties.
Objective: The goal of the present work was the development of a preparation
method of systems supported on γ-Al2O3 palladium nanoparticles with a controlled
size and determination of their thermal stability in oxidizing and reducing
Methods: We demonstrated the preparation of Pd/γ-Al2O3 composite by
precipitation of the size-controlled palladium nanoparticles with a narrow size
distribution from colloidal solution. The composites were characterized by X-ray
diffraction (XRD), and transmission electron microscope (TEM) methods.
Results: The size and size distribution of the nanoparticles supported on γ-Al2O3
were found to be increasing upon precipitation due to strong Pd/γ-Al2O3 interaction.
A significant enlargement of the supported nanoparticles occured at 300°C. The
aggregation of the nanoparticles was observed at temperatures above 500°C
resulting in an increase in their size.
Conclusions: Our findings are not only applicable for the preparation of a model
Pd supported on the γ-Al2O3 catalyst but could be applicable to the designing of the
Pd-containing catalyst for important industrial high-temperature processes.