在γ-Al_2O_3粉体中添加氧化铝胶体，研究其对氧化铝α相变的影响．结果表明，与α氧化铝粉体籽晶相比较，氧化铝胶体也可以起到籽晶的作用；由于其颗粒较小、在γ-Al_2O_3中分散均匀且能与之紧密接触，大大降低了α相变温度，改善了煅...在γ-Al_2O_3粉体中添加氧化铝胶体，研究其对氧化铝α相变的影响．结果表明，与α氧化铝粉体籽晶相比较，氧化铝胶体也可以起到籽晶的作用；由于其颗粒较小、在γ-Al_2O_3中分散均匀且能与之紧密接触，大大降低了α相变温度，改善了煅烧产物的微结构，从而得到分散均匀、平均粒径＜100nm 的α氧化铝超细粉体，根据对粉体形貌 TEM 的观察，初步探讨了添加氧化铝胶体的前驱体α相变的过程。展开更多
The template method for preparing nanostructures entails the synthesis of the desired material within the pores of a nanoporous membrane. In this work, TiO2 nanotubules of the anatase form have been synthesized by sol...The template method for preparing nanostructures entails the synthesis of the desired material within the pores of a nanoporous membrane. In this work, TiO2 nanotubules of the anatase form have been synthesized by sol-gel chemical method using porous anodic alumina as the template. Transmission electron microscopy（TEM）, scanning electron microscopy（SEM）, infrared spectroscopy（IR） and X-ray diffraction were used to investigate the structure and morphology of the TiO2 nanotubules. The results showed that the diameter and length of the obtained nanotubules were determined by the pore size and length of the PAA template. It was founded that through control of immersion time, both tubules and fibrils can be prepared; in addition, the wall thickness of the nanotubules can be varied at will. The result indicated that the sol particles absorbed preferably to the pore walls of the PAA membrane due to the fact that the pore walls were negatively charged and the TiO2 particles were positively charged.展开更多
文摘在γ-Al_2O_3粉体中添加氧化铝胶体，研究其对氧化铝α相变的影响．结果表明，与α氧化铝粉体籽晶相比较，氧化铝胶体也可以起到籽晶的作用；由于其颗粒较小、在γ-Al_2O_3中分散均匀且能与之紧密接触，大大降低了α相变温度，改善了煅烧产物的微结构，从而得到分散均匀、平均粒径＜100nm 的α氧化铝超细粉体，根据对粉体形貌 TEM 的观察，初步探讨了添加氧化铝胶体的前驱体α相变的过程。
文摘The template method for preparing nanostructures entails the synthesis of the desired material within the pores of a nanoporous membrane. In this work, TiO2 nanotubules of the anatase form have been synthesized by sol-gel chemical method using porous anodic alumina as the template. Transmission electron microscopy（TEM）, scanning electron microscopy（SEM）, infrared spectroscopy（IR） and X-ray diffraction were used to investigate the structure and morphology of the TiO2 nanotubules. The results showed that the diameter and length of the obtained nanotubules were determined by the pore size and length of the PAA template. It was founded that through control of immersion time, both tubules and fibrils can be prepared; in addition, the wall thickness of the nanotubules can be varied at will. The result indicated that the sol particles absorbed preferably to the pore walls of the PAA membrane due to the fact that the pore walls were negatively charged and the TiO2 particles were positively charged.
