Abstract
Investigation of selectivity of crystal growth direction in layered double hydroxides is helpful to control their particle sizes in different directions. Mg-Al layered double hydroxides (LDHs) were synthesized by using a coprecipitation method. The influences of aging temperature, aging time, and Mg/Al molar ratio on the crystal structure, the LDHs particle size, and the selectivity of crystal growth in different directions were investigated. The results show that the size of the crystallites in the a direction is larger than that in the c direction for all experimental conditions, indicating faster crystal growth in the a direction than in the c direction. The crystallite sizes in the a and c directions both increase with decreasing Mg/AI molar ratio but with less difference between the sizes in the two directions. Therefore, the crystal growth rate in the c direction increases more than that in the a direction as the Mg/AI molar ratio decreases. The influence of the aging time, aging temperature, and Mg/AI molar ratio on the selectivity of the crystal growth direction can be used to prepare LDHs with selected sizes in the a and c directions.
| Original language | English |
|---|---|
| Pages (from-to) | 672-675 |
| Number of pages | 4 |
| Journal | Tsinghua Science and Technology |
| Volume | 9 |
| Issue number | 6 |
| Publication status | Published - Dec 2004 |
| Externally published | Yes |
Keywords
- Layered double hydroxides
- Particle size
- Selectivity of crystal growth direction