Multiple Growth Mechanisms of 2:1 Type Layered Aluminosilicates during Mineral Transformation

作者：Li, Shangying; He, Hongping; Tao, Qi; Du, Peixin; Chen, Aiqing; He, Yilin; Zhu, Jianxi^*

来源：ACS Earth and Space Chemistry, 2022.

DOI：10.1021/acsearthspacechem.2c00137

• KEYWORDS
• 2
• 1 type layered aluminosilicates
• boehmite
• transformation
• layer growth
• oriented attachment

2:1 type layered aluminosilicates (LAs) such as beidellite, montmorillonite, and paragonite distribute widely in the various environments of the Earth, and they form commonly through the transformation of other minerals under hydrothermal or weathering conditions. Understanding the growth mechanisms of 2:1 type LAs during mineral transformation is of great importance for profoundly revealing their formation processes in the geological environments and a better understanding of the formation of crystal defects within minerals, however, which is not thoroughly revealed. In this study, the transformation of boehmite into 2:1 type LAs was successfully realized under hydrothermal conditions, and the growth mechanisms of 2:1 type LAs during such a mineral transformation were explored using spectroscopic and microscopic characterizations. The results indicated that layers of 2:1 type LAs preferentially extend in the a-b plane at the initial transformation stage and stack along the c-axis with the transformation proceeding. Additionally, some small primary nanoparticles of 2:1 type LAs occasionally attached to each other along the c-axis or in the a-b plane. This revealed that 2:1 type LAs that formed at the interfaces between precursor boehmite and additional amorphous Si mainly grew through the layer growth mechanism occasionally accompanied by the oriented attachment.

• 单位
  中国科学院研究生院