Changing the calcination temperature to tune the microstructure and polishing properties of ceria octahedrons.
Changing the calcination temperature to tune the microstructure and polishing properties of ceria octahedrons.
复制标题
改变煅烧温度来调节二氧化铈八面体的微观结构和抛光性能
作者：
通过在500-900 °C下煅烧由约5 nm的球形初级纳米晶体自组装的八面体CeO 2前驱体，制备了具有不同微观结构和表面特征的CeO 2八面体。结构表征表明，随着煅烧温度从500 °C升高到700 °C，产物保持分级结构，初级纳米晶由球形转变为八面体颗粒。在800 °C的煅烧温度下，初生纳米晶之间发生了明显的熔合，八面体表面变得光滑。当煅烧温度达到900 °C时，形成单晶CeO 2八面体。煅烧温度升高导致八面体微观结构的变化，使八面体的机械硬度增加，表面化学活性（比表面积和表面Ce 3+浓度）降低，从而影响其抛光性能。对K9玻璃的抛光实验表明，随着煅烧温度的升高，抛光速率先增大后减小，表明除了机械硬度外，八面体表面化学活性对材料去除也很重要。由于化学活性和机械硬度的最佳匹配，在700 °C煅烧的CeO 2八面体对K9玻璃具有最高的抛光速率和最好的表面质量。通过在500-900 °C下煅烧分级前驱体，制备了具有不同微观结构的八面体氧化铈磨料。研究了煅烧温度与其微观结构、机械硬度和化学活性的关系。
Ceria octahedrons with different microstructure and surface characteristics were prepared by calcining an octahedral CeO2 precursor self-assembled from spherical primary nanocrystals of about 5 nm at 500–900 °C. Structural characterization revealed that with the calcination temperature increasing from 500 to 700 °C, the products maintained a hierarchical structure and primary nanocrystals changed from spherical to octahedral particles. Significant fusion occurred between the primary nanocrystals and the surface of the octahedrons became smooth at the calcination temperature of 800 °C. Single crystal CeO2 octahedrons were formed when the calcination temperature reached 900 °C. The change in microstructure induced by elevated calcination temperature led to increased mechanical hardness and decreased surface chemical activity (specific surface area and surface Ce3+ concentration) of the octahedrons, which had an impact on their polishing performance. The polishing experiments on K9 glass showed that the polishing rate first increased and then decreased with the increment of calcination temperature, indicating that in addition to the mechanical hardness, the surface chemical activity of the octahedrons is also important for material removal. Owing to the best matching of chemical activity and mechanical hardness, CeO2 octahedrons calcinated at 700 °C exhibited the highest polishing rate and the best surface quality for K9 glass. Octahedral ceria abrasives with varied microstructures were prepared by calcining a hierarchical precursor at 500–900 °C. The relationship between calcination temperature and microstructure, mechanical hardness and chemical activity was investigated.
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影响因子：
6.7
作者：
Dawkins, K.;Rudyk, B. W.;Cadien, K.
通讯作者：
Cadien, K.
具有{111}暴露平面的二氧化铈混合结构的合成、表征和摩擦磨损行为
影响因子：
6.7
作者：
Hu, Pengfei;Chen, Yong;Wang, Zhongchang
通讯作者：
Wang, Zhongchang
影响因子：
9.9
作者：
Dandu, P. R. Veera;Devarapalli, V. K.;Babu, S. V.
通讯作者：
Babu, S. V.
影响因子：
5
作者：
Janos, Pavel;Ederer, Jakub;Opletal, Tomas
通讯作者：
Opletal, Tomas
DOI：
10.1149/2162-8777/ab8393
发表时间：
2020-04-06
影响因子：
2.2
作者：
Netzband, C. M.;Dunn, K.
通讯作者：
Dunn, K.