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Direct Atomic-Scale Insight into the Precipitation Formation at the Lanthanum Hydroxide Nanoparticle/Solution
Yanfu Wei1, Peng Yuan2, Junming Zhou3
1National Observation and Research Station of Coastal Ecological Environments in Macao, Macao Environmental Research Institute, Macau University of Science and Technology, Taipa, Macao 999078, China.
The Journal of Physical Chemistry Letters
|April 21, 2023
Summary
Lanthanum hydroxide nanoparticle interfaces transform into lanthanum phosphate precipitation upon phosphate reaction. This atomic-scale study reveals transformation differences between high- and low-crystalline structures, offering insights into interfacial processes.
Area of Science:
- Materials Science
- Nanotechnology
- Surface Chemistry
Background:
- Precipitation at nanoparticle-solution interfaces is critical for catalysis, adsorption, and energy storage.
- Atomic-scale imaging of these interfaces in solution is challenging due to beam-induced dissolution.
- Lanthanum hydroxide (La(OH)3) nanoparticles are relevant to various applications.
Purpose of the Study:
- To investigate the atomic-scale mechanism of precipitation formation at La(OH)3 nanoparticle-solution interfaces.
- To understand the structural transformation of La(OH)3 nanoparticles upon reaction with phosphate.
- To provide insights into the direct atomic-scale observation of interfacial precipitation.
Main Methods:
- Utilized focused ion beam (FIB) for sample preparation.
- Employed aberration-corrected high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) for atomic-scale imaging.
- Studied La(OH)3 nanoparticle interfaces after reaction with phosphate in solution.
Main Results:
- Observed atomic-scale structure transformation at both high- and low-crystalline La(OH)3 nanoparticle surfaces.
- Low-crystalline La(OH)3 predominantly transformed into lanthanum phosphate (LaPO4) precipitation.
- High-crystalline La(OH)3 showed partial conversion to LaPO4 precipitation, with limited long-term transformation.
Conclusions:
- The study elucidates the distinct precipitation pathways of La(OH)3 nanoparticles based on crystallinity.
- The findings demonstrate a viable method for atomic-scale observation of interfacial precipitation.
- Results offer valuable references for studying common solid-solution interface precipitation phenomena.
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