CeO₂ nanoparticles have been proven to be competent photocatalysts for environmental applications because of their strong redox ability, nontoxicity, long‐term stability, and low cost. We have synthesized CeO₂ nanoparticles via solution combustion method using ceric ammonium nitrate as an oxidizer and ethylenediaminetetraacetic acid (EDTA) as fuel at 450 °C. These nanoparticles exhibit good photocatalytic degradation and antibacterial activity. The obtained product was characterized by various techniques. X‐ray diffraction data confirms a cerianite structure: a cubic phase CeO₂ having crystallite size of 35 nm. The infrared spectrum shows a strong band below 700 cm⁻¹ due to the Ce−O−Ce stretching vibrations. The UV/Vis spectrum shows maximum absorption at 302 nm. The photoluminescence spectrum shows characteristic peaks of CeO₂ nanoparticles. Scanning electron microscopy (SEM) images clearly show the presence of a porous network with a lot of voids. From transmission electron microscopy (TEM) images, it is clear that the particles are almost spherical, and the average size of the nanoparticles is found to be 42 nm. CeO₂ nanoparticles exhibit photocatalytic activity against trypan blue at pH 10 in UV light, and the reaction follows pseudo first‐order kinetics. Finally, CeO₂ nanoparticles also reduce Cr^VI to Cr^III and show antibacterial activity against Pseudomonas aeruginosa.

The impact of a CeO₂-ZnO nanocomposite on the photocatalytic and antibacterial properties compared to bare ZnO was investigated. A CeO₂-ZnO nanocomposite was synthesized using Acacia nilotica fruit extract as a novel fuel by a simple solution combustion method. The obtained CeO₂-ZnO nanocomposite was confirmed structurally by XRD, FTIR, Raman and UV-DRS and morphologically by SEM/TEM analysis. The XRD pattern indicates the presence of both hexagonal Wurtzite-structured ZnO (major) and cubic-phase CeO₂ (minor). FTIR shows the presence of a Ce-O-Ce vibration at 468 cm⁻¹ and Zn-O vibration at 445 cm⁻¹. The existence of a band at 460 cm⁻¹ confirmed the F_2g Raman-active mode of the fluorite cubic crystalline structure for CeO₂. Diffused reflectance spectroscopy was used to estimate the bandgap (E_g) from Kubelka–Munk (K–M) theory which was found to be 3.4 eV. TEM analysis shows almost spherical-shaped particles, at a size of about 10–15 nm. The CeO₂-ZnO nanocomposite shows a good BET specific surface area of 30 m²g⁻¹. The surface defects and porosity of the CeO₂-ZnO nanocomposite caused methylene blue (MB) dye to degrade under sunlight (88%) and UV light (92%). The CeO₂-ZnO nanocomposite also exhibited considerable antibacterial activity against a pathogenic bacterial strain.

RGO wrapped MoO₃ NPs were successfully synthesized via simple and scalable steps as potential anode materials for Li-ion batteries.