期刊
MOLECULAR SYSTEMS DESIGN & ENGINEERING
卷 7, 期 1, 页码 34-43出版社
ROYAL SOC CHEMISTRY
DOI: 10.1039/d1me00078k
关键词
-
类别
资金
- National Science Foundation, Division of Materials Research, Electronic and Photonic Materials Program [DMR-1701774]
- DOE Office of Science [DE-SC0012704]
The study found that the crystallization of 2-decyl-7-phenyl-[1]benzothieno[3,2-b][1]benzothiophene during its deposition from solution goes through a transient liquid crystal state before reaching the final stable crystalline phase. The long-lived monolayer-stacked intermediate state does not act as a template for the bilayer-stacked crystalline phase, instead, the grain structure is replaced through nucleation. The dynamics during the transition process are correlated with the time interval that the transient thin film coexists with the evaporating solvent.
Understanding and manipulating crystallization processes has been an important challenge for solution-processed organic thin films, both for fundamental studies and for fabricating thin films with near-intrinsic charge transport properties. We report an in situ X-ray scattering study of the crystallization of 2-decyl-7-phenyl-[1]benzothieno[3,2-b][1]benzothiophene (Ph-BTBT-C-10) during its deposition from solution. At temperatures modestly below the smectic-E/crystalline phase boundary, the crystallization goes through a transient liquid crystal state before reaching the final stable crystalline phase. Significant dynamics occur in the first few seconds of the transition, which are observed through fluctuations in the X-ray scattering intensity, and are correlated with the time interval that the transient thin film coexists with the evaporating solvent. The transition to the stable crystalline phase takes minutes or even hours under these conditions, which may be a result of the asymmetry of the molecule. Transient phases are of potential interest for applications, since they can act as a route to self-assembly of organic thin films. However, our observations show that the long-lived monolayer-stacked intermediate state does not act as a template for the bilayer-stacked crystalline phase. Rather, the grain structure is replaced through nucleation, where the nucleation free-energy barrier is related to a potential barrier that prevents molecules to flip their long axis by 180 degrees.
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