近日，美国加州大学伯克利分校Naomi S. Ginsberg团队实现了在亚稳液体双节点附近增强纳米级带电胶体结晶。相关论文于2025年8月26日发表在《自然—物理学》杂志上。

在避免动力学陷阱的同时，实现对结晶主题非经典成核的预测控制将是设计具有新功能材料的一步。

研究组通过诱导纳米晶体自下而上组装成有序阵列或超晶格来解决这些挑战。利用静电——而不是密度——来调节粒子之间的相互作用，他们观察到自组装在亚稳液相中进行。研究组系统地研究了在原位和实时小角x射线散射中作为淬火条件函数的相行为。通过拟合胶体、液体和超晶格模型，他们提取了各相的时间演化和系统相图，并发现它们与短程吸引相互作用是一致的。

利用相图的预测能力，研究组建立了超过三个数量级的自组装速率控制，并确定了一步和两步自组装制度，其中只有后者意味着亚稳液体作为中间体。相对于等效的一步路径，亚稳液体的存在增加了超晶格的形成速度，并且超晶格的有序度随着速度的增加而增加，揭示了促进和增强有序组装的可推广的动力学策略。

附：英文原文

Title: Enhancing nanoscale charged colloid crystallization near a metastable liquid binodal

Author: Tanner, Christian P. N., Wall, Vivian R. K., Portner, Joshua, Jeong, Ahhyun, Das, Avishek, Utterback, James K., Hamerlynck, Leo M., Raybin, Jonathan G., Hurley, Matthew J., Leonard, Nicholas, Wai, Rebecca B., Tan, Jenna A., Gababa, Mumtaz, Zhu, Chenhui, Schaible, Eric, Tassone, Christopher J., Limmer, David T., Teitelbaum, Samuel W., Talapin, Dmitri V., Ginsberg, Naomi S.

Issue&Volume: 2025-08-26

Abstract: Achieving predictive control over crystallization using non-classical nucleation while avoiding kinetic traps would be a step towards designing materials with new functionalities. We address these challenges by inducing the bottom-up assembly of nanocrystals into ordered arrays, or superlattices. Using electrostatics—rather than density—to tune the interactions between particles, we watch self-assembly proceed through a metastable liquid phase. We systematically investigate the phase behaviour as a function of quench conditions in situ and in real time using small-angle X-ray scattering. By fitting to colloid, liquid and superlattice models, we extract the time evolution of each phase and the system phase diagram, which we find to be consistent with short-range attractive interactions. Using the predictive power of the phase diagram, we establish control of the self-assembly rate over three orders of magnitude, and we identify one- and two-step self-assembly regimes, with only the latter implicating the metastable liquid as an intermediate. The presence of the metastable liquid increases the superlattice formation rate relative to the equivalent one-step pathway, and the superlattice order increases with the rate, revealing a generalizable kinetic strategy for promoting and enhancing ordered assembly.

DOI: 10.1038/s41567-025-02996-5

Source: https://www.nature.com/articles/s41567-025-02996-5