Realignment of Nanocrystal Aggregates into Single Crystals as a Result of Inherent Surface Stress. Issue 41 (19th July 2016)

• Record Type: Journal Article
• Authors: Liu, Zhaoming; Pan, Haihua; Zhu, Genxing; Li, Yaling; Tao, Jinhui; Jin, Biao; Tang, Ruikang
• Is Part Of: Angewandte Chemie international edition. Volume 55:Issue 41(2016)
• Page Start: 12836
• Page End: 12840
• Publication Date: 2016-07-19
• Subjects: aggregation -- calcium carbonate -- crystal growth -- crystal orientation -- surface stress; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201603794
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: Crystallization by particle attachment is widely observed in both natural and synthetic environments. Although this form of nonclassical crystallization is generally described by oriented attachment, random aggregation of building blocks to give single‐crystal products is also observed, but the mechanism of crystallographic realignment is unknown. We herein reveal that random attachment during aggregation‐based growth initially produces a nonoriented growth front. Subsequent evolution of the orientation is driven by the inherent surface stress applied by the disordered surface layer and results in single‐crystal formation by grain‐boundary migration. This mechanism is corroborated by measurements of orientation rate versus external stress, which demonstrated a predictive relationship between the two. These findings advance our understandings about aggregation‐based growth via nanocrystal blocks and suggest an approach to material synthesis that takes advantage of stress‐induced coalignment. Abstract : Fall in ! During random‐attachment‐based crystal growth, it was found that the evolution of crystal orientation is driven by the inherent surface stress, which eventually generates a single crystal (see picture). This mechanism is corroborated by measurements of orientation rate versus stress, for which a predictive relationship was identified.