Determination of Particle Size Distribution by Laser Diffraction of Doped‐CeO₂ Powder Suspensions: Effect of Suspension Stability and Sonication

Abstract

The particle size distributions (PSDs) of metal oxide powders are often determined by analyzing suspensions of powders using laser diffraction (e.g. Malvern MasterSizer 2000). Particle agglomeration can effectively bias the resulting distribution towards “unrealistic” particle sizes. Solutions to avoid this problem must be found if a particle distribution based on the elemental or primary particle sizes is desired. In this work, the particle size distribution of doped‐CeO2 powders was studied. These powders show a crystalline single phase structure of controlled stoichiometry as determined by X‐ray diffraction and ICP analysis. The apparent size distribution was found to be a strong function of suspension stability. Dispersant agents (PBTCA and phosphonoacetic acid) and suspension pH affected stability as characterized by zeta potential measurements. Sonication of the suspensions further enhanced particle de‐agglomeration. Finally, only the combined effect of a dispersant agent, pH adjustment of the suspension and sonication provided a primary particle size distribution. The results presented in this work can be used in the analysis of similar ceramic powders in which strong particle agglomeration is present.

Effects of the microwave heating on the properties of gadolinium-doped cerium oxide prepared by polyol method

“…[4][5][6][7][8] Gadolinium doped ceria (GDC), in particular, has received a lot of attention as alternative to yttria stabilized zirconia (YSZ) for its high ionic conductivity at 600 • C. 9 A number of different methods are currently used to prepare doped-ceria systems, including hydrothermal, 10,11 microemulsion, 11 precipitation 12 and sol-gel. 10,13 In most of these cases however, an additional calcination step (at 400-600 • C) is generally required to transform the initial amorphous powder into a crystalline one.…”

Crosslinking systems and film properties for surfactant-free latexes based on anhydride-containing polymers

“…The reduced stabilization resulted in particle aggregation when the pH was lowered to below 5, as can be seen by a significant increase in particle size (from w150 nm to >1 mm) for the PSMA-based latex. The modulus of the z-potential at this pH was close to 30 mV, which is generally considered to be the value above which stable particles are obtained [22,23]. Due to the flocculation the latex with DAH could not be studied at lower pH values.…”

New In-situ Sampling and Analysis of the Production of CeO2 Powders from Liquid Precursors using a Novel Wet Collection System in a rf Inductively Coupled Thermal Plasma Reactor. Part 1: Reactor System and Sampling Probe

“…The pH was adjusted with sodium hydroxide 5N solution (Fisher SS256B). Further details of this technique are explained elsewhere [26]. The X-ray diffraction analysis was done using a PHILIPS PW1710 powder X-ray diffraction system equipped with a copper X-ray source operated at 800 W. The Philips PC APD and Philips PC Identify software were used.…”