Ceria‐ and Cu‐Doped Ceria Nanocrystals Synthesized by the Hydrothermal Methods

Ceria‐ or Cu‐doped ceria nanocrystals with a uniform diameter of about 4–5 nm have been successfully synthesized directly via a hydrothermal treatment of the precipitate Ce(OH) 3 (purple) or Cu‐doped Ce(OH) 3 in a strongly basic solution of sodium hydroxide at 180°C for 24 h. The formation of the nanocrystals involves the transformation of Ce (III) to Ce (IV) under the hydrothermal conditions. The as‐synthesized ceria‐ and Cu‐doped ceria crystalline nanoparticles have high specific surface areas, pore volumes, and pore sizes.