Nearest-neighbour nanocrystal bonding dictates framework stability or collapse in colloidal nanocrystal frameworks
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Updated: Mar 4, 2026
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Teresa E Williams1, Daniela Ushizima, Chenhui Zhu
1Graduate Group in Applied Science and Technology, University of California-Berkeley, Berkeley, CA 94720, USA.
Abstract:
Block copolymers serve as architecture-directing agents for the assembly of colloidal nanocrystals into a variety of mesoporous solids. Here we report the fundamental order-disorder transition in such assemblies, which yield, on one hand, ordered colloidal nanocrystals frameworks or, alternatively, disordered mesoporous nanocrystal films. Our determination of the order-disorder transition is based on extensive image analysis of films after thermal processing. The number of nearest-nanocrystal neighbours emerges as a critical parameter dictating assembly outcomes, which is in turn determined by the nanocrystal volume fraction (fNC). We also identify the minimum fNC needed to support the structure against collapse.
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