Synthesis Of Nd³⁺ Doped Calcium Zirconate-based Changing Colour Pigment

With the development of ceramic ink-jet printing technology, the demands ofpersonalized decoration are increase in recent years. The research of new kind of functionaldecorative pigments is urgent. In this thesis, we carried out depth resesrch relate to synthesisthe neodymium powder doped calcium zirconate, and synthesized successfully a newneodymium doped calcium zirconate colour pigment by coprecipitation method and solutioncombustion method. The powder was mainly characterized by XRD, DSC-TG, SEMtechniques.The changing colour pigment powder with better performances was prepared viaoptimized coprecipitation method. The effects of ultrasonic powder, precipitant, anddispersants applied in co-precipitation method on the morphology, size and size distributionof changing colour pigment particle were investigated. The results indicated that whenzirconyl nitrate was used as source of zirconium, ammonium oxalate or ammonium carbonatewas used as precipitant, and polyethylene glycol6000was used as dispersant under600Hzultrasonic powder, the changing colour pigment with uniform morphology, uniform particlesize were synthesized with co-precipitation method after two hours calcination at1200℃. Theinfluences of the content of neodymium, calcination temperature, mineralizers and co-dopedmetal ions on the effect of coloration and changing colour were studied. When the molar ratioEab1(D65/A) value could reach2.12, which was enough to meet peopleperception of chromatism. Coloration and changing colour could be strengthened byimpoving the calcination temperature. We got the pigment of similar coloration and changingcolour effects in1200℃compared to1300℃calcined sample. The calcination temperaturecould be decreased to1100℃by adding6wt%NH4F mineralizer, pigment color and changingcolor effect was no obvious difference with the1200℃calcined sample. Pigment color andcolor changing were fundamentally changed when neodymium doped calcium zirconate wasco-doped Cr3+, Fe3+and Pr4+, while a certain amount of Cu2+could reinforce the effect ofcolor and color changing.We found that the changing colour pigment powder could be rapidly synthesized underthe condition of lower calcinations. Experiment results indicated that combustion agent andthe molar ratio of combustion agent and nitrate played an important role in the performancesof coloration and changing colour. When the molar ratio of β-alanine and nitrate was0.9,performance of pigment was better. The influence of the nert salt NaCl to pigment powder’sparticle size was further studied. Experimental results showed that the particle of pigment powder was narrow when the mole ratio of NaCl and nitrate was1. The formation process ofsalt-assisted Combustion Synthesis of neodymium doped calcium zirconate was discussedfurther.