摘要
In this work, monodispersed layered double hydroxide (Ca-AI LDHs) nanoparticles were synthesized by hydrothermal coprecipitation. Uniform thin films of layered double hydroxide on porous anodic aluminum oxide (AAO) substrates were formed by a direct precipitation process in a homogeneous suspension containing monodispersed Ca-AI layered double hydroxide nanoparticles. It was found that the formation of a designed hydrotalcite-like phase is strongly dependent on the [Ca 2+] [Al 3+] ratios, and that a minor CaCO 3 phase could possibly form simultaneously, which is attributed to the greater insolubility of CaCO 3 and the incompatibility of the ionic size of AI and Ca. The optimal CO 2 adsorption capacity appears in the layered Ca-OH-AI structure with the composition ratio of 3:1. Furthermore, the CO 2 adsorption mechanism varies with treatment temperature. Below 400 °C, the CO 2 adsorption is attributed to the LDH structure with a large surface area and pore volume, but above that the adsorption is due to the formation of CaCO 3 and CaO. The permeation behavior and CO 2 absorption can be explained by a preferable chemical and physical absorption of CO 2 on the layered double hydroxide and porous structure of the membrane.
| 原文 | English |
|---|---|
| 頁（從 - 到） | 4716-4720 |
| 頁數 | 5 |
| 期刊 | Journal of Nanoscience and Nanotechnology |
| 卷 | 10 |
| 發行號 | 7 |
| DOIs | |
| 出版狀態 | Published - 7月 2010 |