Hybrid Material in the Cerium(III) Nitrate–Chitosan–Urea System

Nanoscale CeO2 has been prepared under conditions of homogeneous hydrolysis of cerium(III) nitrate in the presence of urea and chitosan as a template. Nanosized CeO2 has been obtained from an intermediate hybrid material containing cerium hydroxocarbonates, chitosan in basic form, and urea from a reaction mixture where ratio of Ce(NO3)3·6H2O and urea precursors was 1 : 15 or more. Thermal treatment of intermediate product at 300°C for 1 h is sufficient for the transformation of cerium hydroxocarbonates into cerium oxide as a light yellow powder with nanoparticle size (coherent scattering region) of 8 nm. The synthesis of nanomaterials in the biopolymer makes it possible to control the shape, size, and micromorphology of hydroxocarbonate particles. The results were compared with the production of cerium hydroxocarbonates with other templates and preparation of cerium oxide by rapid precipitation with ammonia.