In situ NMR reveals real-time nanocrystal growth evolution via monomer-attachment or particle-coalescence.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 33431908.
- Also identified by DOI 10.1038/s41467-020-20512-6 and PMC identifier 7801738.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Understanding inorganic nanocrystal (NC) growth dynamic pathways under their native fabrication environment remains a central goal of science, as it is crucial for rationalizing novel nanoformulations with desired architectures and functionalities. We here present an in-situ method for quantifying, in real time, NCs' size evolution at sub-nm resolution, their concentration, and reactants consumption rate for studying NC growth mechanisms. Analyzing sequential high-resolution liquid-state <sup>19</sup>F-NMR spectra obtained in-situ and validating by ex-situ cryoTEM, we explore the growth evolution of fluoride-based NCs (CaF<sub>2</sub> and SrF<sub>2</sub>) in water, without disturbing the synthesis conditions. We find that the same nanomaterial (CaF<sub>2</sub>) can grow by either a particle-coalescence or classical-growth mechanism, as regulated by the capping ligand, resulting in different crystallographic properties and functional features of the fabricated NC. The ability to reveal, in real time, mechanistic pathways at which NCs grow open unique opportunities for tunning the properties of functional materials.