Influence of Different Surfactants on Morphology of Single Crystal Ce2O(CO3)2H2O and Formation Mechanism

Three kinds of ultra-fine Ce2O(CO3)2H2O powders with different morphologies were prepared by adding CTAB, PEG19000 and OP-10 to a solution of Ce2O(NO3)36H2O and urea according to the principle and the characteristics of the homogeneous precipitation method. The products were characterized by TEM and XRD. The results showed that the precursor was a single crystal, and that different surfactants had different influences on the morphology of the products. The cationic surfactant CTAB had little effect on crystal morphology merely reducing its size. Nonionic surfactants PEG19000 and OP-10 are both able to change the crystal morphology to a much greater extent. Adding PEG19000 produces an array of rod-like particles with ordered formation and uniform dimension. Meanwhile, in the system of OP-10, a sort of flower-like pattern with a dispersed center can be prepared. The formations of ultra-fine Ce2O(CO3)2H2O powders with different morphologies occurred because of the mechanism of formation and grain growth.