Stabilization of ZrO2 Powders via ALD of CeO2 and ZrO2

Abstract

ZrO2 powders were modified by atomic layer deposition (ALD) with CeO2 and ZrO2, using Ce(TMHD)4 and Zr(TMHD)4 as the precursors, in order to determine the effect of ALD films on the structure, surface area, and catalytic properties of the ZrO2. Growth rates were measured gravimetrically and found to be 0.017 nm/cycle for CeO2 and 0.031 nm/cycle for ZrO2. The addition of 20 ALD cycles of either CeO2 or ZrO2 was found to stabilize the surface area of the ZrO2 powder following calcination to 1073 K and to suppress the tetragonal-to-monoclinic transition. Shrinkage of ZrO2 wafers was also suppressed by the ALD films. When used as a support for Pd in CO oxidation, the CeO2-modified materials significantly enhanced rates due to interactions between the Pd and the CeO2. Potential applications for modifying catalyst supports using ALD are discussed.

Keywords

• ALD
• CeO2
• ZrO2
• CO oxidation
• sintering
• oxygen storage