期刊
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
卷 13, 期 36, 页码 8502-8508出版社
AMER CHEMICAL SOC
DOI: 10.1021/acs.jpclett.2c01829
关键词
-
类别
资金
- Energy Division of CEA
- French Alternative Energies and Atomic Energy Commission
Crystallization from solution often involves transient, non-crystalline states such as reactant-rich liquid droplets and amorphous particles. In this study, the crystallization process of cerium oxalate was investigated and a metastable chemical equilibrium between liquid droplets and solid amorphous particles was observed. Contrary to expectations, reactant-rich droplets do not transform into amorphous solids, but instead, amorphous and reactant-rich liquid phases coexist for a certain period of time.
Crystallization from solution often occurs via nonclassical routes; that is, it involves transient, non-crystalline states like reactant-rich liquid droplets and amorphous particles. However, in mineral crystals, the well-defined thermodynamic character of liquid droplets and whether they convert -or not -into amorphous phases have remained unassessed. Here, by combining cryo-transmission electron microscopy and X-ray scattering down to a 250 ms reaction time, we unveil that crystallization of cerium oxalate involves a metastable chemical equilibrium between transient liquid droplets and solid amorphous particles: contrary to the usual expectation, reactant-rich droplets do not evolve into amorphous solids. Instead, at concentrations above 2.5 to 10 mmol L-1, both amorphous and reactant-rich liquid phases coexist for several tens of seconds and their molar fractions remain constant and follow the lever rule in a multicomponent phase diagram. Such a metastable chemical equilibrium between solid and liquid precursors has been so far overlooked in multistep nucleation theories and highlights the interest of rationalizing phase transformations using multicomponent phase diagrams not only when designing and recycling rare earths materials but also more generally when describing nonclassical crystallization.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据