Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, 7610001, Israel.
Department of Chemical Research Support, Weizmann Institute of Science, Rehovot, 7610001, Israel.
Nat Commun. 2021 Jan 11;12(1):229. doi: 10.1038/s41467-020-20512-6.
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 F-NMR spectra obtained in-situ and validating by ex-situ cryoTEM, we explore the growth evolution of fluoride-based NCs (CaF and SrF) in water, without disturbing the synthesis conditions. We find that the same nanomaterial (CaF) 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.
理解在其原生制造环境下的无机纳米晶体（NC）生长动态途径仍然是科学的核心目标，因为这对于合理化具有所需结构和功能的新型纳米制剂至关重要。我们在这里提出了一种原位方法，用于实时定量测量 NC 的尺寸演变，以亚纳米分辨率测量其浓度和反应物消耗率，以研究 NC 生长机制。通过原位和非原位低温透射电子显微镜（cryoTEM）分析获得的连续高分辨率液体状态 F-NMR 光谱，并进行验证，我们探索了氟化物基 NC（CaF 和 SrF）在水中的生长演变，而不会干扰合成条件。我们发现，相同的纳米材料（CaF）可以通过颗粒聚集或经典生长机制生长，这由封端配体调节，从而导致所制备的 NC 的不同晶体学性质和功能特征。实时揭示 NC 生长的机制途径的能力为调整功能材料的性能开辟了独特的机会。
