Effect of Microgravity on Synthesis of Nano Ceria

Abstract

Cerium oxide (CeO2) was prepared using a controlled-precipitation method under microgravity at the International Space Station (ISS). For comparison, ceria was also synthesized under normal-gravity conditions (referred as control). The Brunauer-Emmett-Teller (BET) surface area, pore volume and pore size analysis results indicated that the ceria particles grown in space had lower surface area and pore volume compared to the control samples. Furthermore, the space samples had a broader pore size distribution ranging from 30-600 Å, whereas the control samples consisted of pore sizes from 30-50 Å range. Structural information of the ceria particles were obtained using TEM and XRD. Based on the TEM images, it was confirmed that the space samples were predominantly nano-rods, on the other hand, only nano-polyhedra particles were seen in the control ceria samples. The average particle size was larger for ceria samples synthesized in space. XRD results showed higher crystallinity as well as larger mean crystal size for the space samples. The effect of sodium hydroxide concentration on synthesis of ceria was also examined using 1 M and 3 M solutions. It was found that the control samples, prepared in 1 M and 3 M sodium hydroxide solutions, did not show a significant difference between the two. However, when the ceria samples were prepared OPEN ACCESSCatalysts 2015, 5 1307 in a more basic medium (3 M) under microgravity, a decrease in the particle size of the nano-rods and appearances of nano-polyhedra and spheres were observed.

High Surface Area Ceria Nanoparticles via Hydrothermal Synthesis Experiment Design

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Effect of Cerium Oxide Nanoparticles as Antibacterial on Staphylococcus Aureus Bacteria

“…Cerium oxide is a very common rare earth metal oxide also known as ceria or ceric oxide. Cerium oxide nanoparticles is nowadays used as antibacterial agent, oxidation resistant coatings and in oxygen sensors (Chen et al, 2014;Hilaire et al, 2014;Soykal et al, 2015). Cerium oxide nanoparticles have exceptional physical and chemical properties due to their small size, including a high magnetic moment and highly strong complexation reactivity (Hilaire et al, 2014).…”