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Abstract：
It is important to adapt the morphology of CeO2 to different applications. A novel flaky CeO2 with nanocrystals was successfully synthesized using the ordinal precipitation method and calcination. The size of the flaky CeO2 was about 10 μm, and the nanocrystals were about 100 nm. Under the action of the precipitant NH4HCO3, Ce3+ nucleated in large quantities. The nanosized crystals gathered into flakes driven by the surface energy. As the calcination temperature increased, the grains grew slowly by mass transfer due to the slow diffusion of reactants. By adding AlOOH to the starting material, the Al3+ doped into the CeO2 increased the content of Ce3+ in the CeO2, which improved the chemical activity of the CeO2. When the starting material\'s Al:Ce ratio was 5:1, the Ce3+ increased to 31.11% in the CeO2, which provided good application potential in the polishing field. After polishing by the slurry of flaky CeO2 for 1 h, the SiC surface roughness reduced from 464 nm to 11 nm.
摘要：
重要的是使CeO2的形态适应不同的应用。使用顺序沉淀法和煅烧成功合成了具有纳米晶体的新型片状CeO2。片状CeO2的尺寸约为10μm，纳米晶体约为100nm。在沉淀剂NH4HCO3的作用下，Ce3+大量成核。纳米尺寸的晶体在表面能的驱动下聚集成薄片。随着煅烧温度的升高,由于反应物的缓慢扩散，通过传质使晶粒生长缓慢。通过向原料中加入AlOOH，将Al3+掺杂到CeO2中,提高了CeO2中Ce3+的含量,提高了CeO2的化学活性。当起始材料的Al：Ce比为5：1时，CeO2中的Ce3增加到31.11％，这在抛光领域提供了良好的应用潜力。用片状CeO2浆料抛光1h后，SiC表面粗糙度从464nm降低到11nm。
