Effect of dispersant on CaCu3Ti4O12 powders synthesized by oxalate co-precipitation method

CaCu3Ti4O12 (CCTO) and its precursors with different morphologies were obtained by using Polyethylene Glycol (PEG) as suitable capping agent during the co-precipitation procedure. The precursors were calcined at 850 °C and then sintered at 1100 °C. Results showed that quasi-spherical precursors and spherical CCTO powders agglomerated slightly in case of not adding PEG. However, under the influence of PEG, the precursors were flower-like or lamellar and CCTO powders with smaller grain size assembled into 2-D planes. The XRD patterns confirmed the formation of CCTO crystal phase and no new peaks appeared whether the dispersant was added or not. The dielectric properties of the final products were also affected by the presence of PEG.

► PEG did not affect the phase composition of the CCTO powders.
► Lower temperature synthesis of CCTO was feasible with the addition of PEG.
► Morphology of CCTO precursor changed to flower-like or lamellar with PEG.
► Dielectric properties of CCTO became more independent of frequency variation.