製備具再分散性之立方體奈米氧化鋯結晶粒子

Preparation of dispersible c-ZrO2 nanocrystals

白謹通(Chin-tung Pai)

指導教授 ： 蔣孝澈

國立中央大學/工學院/化學工程與材料工程學系/碩士(2012年)

摘要

本實驗的目的是製備出具有均一粒徑且經過改質後可以再分散在溶劑中的立方二氧化鋯奈米結晶粒子，此一製成實驗步驟較為簡單，並已經放大到公斤級，本實驗討論合成過程中的配方、清洗和改質條件所造成的影響。
使用碳酸鋯當作合成奈米氧化鋯的原料，透過調整反應物中二氧化鋯、NaOH和水的比例，控制奈米二氧化鋯粒子的大小，再利用碳酸氫氨水溶液進行離子交換，降低氧化鋯表面上Na離子的含量，經過離子交換後的沉澱物可以添加不同的有機酸進行改質，改質過後的奈米氧化鋯粒子經過乾燥，可以在常溫下以粉體的方式保存，並且分散到不同的有機溶劑中。
在反應物氧化鋯含量22 wt%和 NaOH 22.3 wt%的條件下，以烘箱加熱110 oC加熱6小時，可以得到結晶大小為3.1 nm的立方晶相的奈米氧化鋯粒子，經過丁酸改質過後的粉體分散在甲苯中，配置成氧化鋯固含量50 wt%的分散液，在可見光波長600 nm穿透度82%，DLS的平均粒徑為15.6 nm，粉體密度為2.5 g/cm3，粉體折射率為1.7。

關鍵字

氧化鋯 ； 分散 ； 奈米粒子 ； 立方晶體 ； 改質有機酸

並列摘要

The purpose of this experiment was formatted the dispersible c-ZrO2 nanocrystals with digestion. The organic acid grafted c-ZrO2 nanocrystals can be stabilized in different solvents. This synthesis route is relatively simple and has been developed into large-scale. In this study, we discussed the condition of the reactant, ion exchange and modification of the synthesis process.
We used zirconium basic carbonate as the raw materials for the synthesis of zirconia nanocrystals. We adjusted the reactant ratio of zirconium dioxide, NaOH and water, controlling the particle size of zirconia nanoparticles. After reaction we used ammonium bicarbonate solution to ion exchange, the Na+ on zirconia nanoparticles surface would reduce. This precipitate can be modified with different organic acids and the organic acid grafted ZrO2 can dried into powders. The modified powders can disperse in different solvent.
The particular sample was prepared by the 110oC/6 hours digestion of a mixture having 22.3 wt % ZrO2 equivalent and 22 wt% NaOH. It can obtained the cubic zirconia nanocrystals of 3.1 nm. The dispersion of BA grafted ZrO2 in toluene at 50 wt% had the transparency 82 % at visible wavelength of 600 nm. The average particle size is 15.6 nm from DLS. The density of BA-ZrO2 powder was 2.5 g/cm3 and refractive indexes was 1.7.

並列關鍵字

nanocrystals ； dispersion ； modification ； cubic ； ZrO2 ； zirconia

參考文獻

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