Effect of Synthesis Parameters on the Color Performance of Blue CoAl2O4 Ceramic Pigment

Blue ceramic nano pigment of CoAl2O4 has been synthesized by a co-precipitation method. The reactions conditions (stirring time and stoichiometric ratio) for the preparation of precipitated compound and the calcination conditions (temperature and time) have been optimized for the proper particle synthesis. In addition, the effects of different capping agents (pyrrolidinone, N-cetyl-N,N,N-trimethylammonium bromide, triethylamine, and oleic acid) on the characteristic features of CoAl2O4 have been analyzed by X-ray diffraction and color analysis. Synthesized samples have been identified as spinel (CoAl2O4). The spectroscopic results indicate that minor changes have been seen and the desired electronic transitions in Co2+ in tetrahedral coordination have been achieved. The color performance of pigments has been increased and particle sizes have been decreased with the capping agent addition. The lowest b* values have been obtained in the TEA added samples. The crystallite sizes have been estimated by using the Scherrer equation. In comparison of the capping agent added samples, the smallest particles have been obtained in CTAB added samples.