Nanocrystalline cerium oxide is synthesized by precipitation method using a mixture of water solvent and isopropanol with a ratio of 1: 6 at room temperature has been successfully synthesized. Nanocrystalline cerium oxide was characterized by using X-Ray diffraction (XRD), DRS UV-Vis Analytic, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). XRD results showed the peak intensity of Cerium Oxide (CeO2) was absorbed at an angle of 2Ɵ which is 28.7o, 33.2 o, 47.5 o, 56.7 o, 59.2 o, 69.5 o, 76.8 o, 79 , 1o, 88.3 o, and 95.5 o. The size of cerium oxide crystals was calculated using the debye schrerer equation and obtained a crystal size value of 11.04 - 99.19 nm. Based on the XRD data it can be concluded that the crystal size is included in the nanocrystal category with a size range of 1-100 nm. Microstructure results were analyzed by SEM and TEM showing rounded cerium oxide particles clumping like fine crystals. Optical properties of nanocrystalline cerium oxide were analyzed by DRS UV-Vis Analytic which showed that cerium oxide absorbs UV light at wavelengths of 200, 245 and 290 nm with an energy band gap value of 2.43 eV.

Silver nanoparticles have been successfully synthesized using a chemical reduction method at room temperature using glucose as a reducing agent, silver nitrate as a source of nitrate, polyvinyl alcohol (PVA) as a stabilizing agent. The purpose of this research was to determine the effect of the mole ratio of reducing agent Glu / Ag and percentage (%) PVA (b/v) in the silver nanoparticle synthesis of the resulted product. Product characterization was analyzed by UV-Vis Spectrophotometers, XRD, and TEM. The Analysis of the UV-Vis spectra showed that the most stable particles were silver nanoparticles used PVA 3% and Glu / Ag. 1: 8 on λmax 415 to 417 nm. TEM’s characterization showed that silver nanoparticles were spherical with a dominant size range of 12,28 nm – 38,45 nm nm. The newly synthesized silver nanoparticles may have a potential for antibacterial applications.

Nanocrystalline cerium oxide is synthesized by precipitation method using a mixture of water solvent and isopropanol with a ratio of 1: 6 at room temperature has been successfully synthesized. Nanocrystalline cerium oxide was characterized by using XRD, DRS UV-Vis Analytic, SEM and TEM. XRD results showed the peak intensity of Cerium Oxide (CeO2) was absorbed in an angle of 2Ɵ which is 28.

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Silver-cerium nanoparticles had been successfully synthesized using the sol-gel method by silver nitrate as a source of silver and cerium nitrate hexahydrate as a source of cerium. The synthesized silver-cerium nanoparticles had been characterized by X-ray diffraction,transmission electron microscopy, and scanning electron microscopy-energy dispersive X-ray. Based on the results of XRD and TEM analysis showed silver-cerium nanoparticles were spherical with the dominant size range of 8.9 -12.73 nm. SEM-EDX analysis showed silver nanoparticles covered by cerium nanoparticles that were known as the core-shell structure. Silver nanoparticles doped with cerium nanoparticles (CeONP) showed an increase in inhibitory with an increase a zone of inhibition after being doped with cerium nanoparticles. The disinfection effect of Ag-doped CeONP was more pronounced on Staphylococcus aureus than Escherichia coli, although the difference was not wide.