Download file (2.63 MB)
Download as zip (2.3 MB)

Collection

Citation

Description:

Solid-liquid phase transitions are fundamental physical processes for materials, but atomically-resolved microscopy has yet to capture the full dynamics of such a transition. We have developed a new technique for controlling melting and freezing of 2D molecular layers on a graphene field-effect transistor (FET) that allows us to image phase transition dynamics via atomically-resolved scanning tunneling microscopy. This is achieved by applying electric fields to an F4TCNQ-decorated graphene FET that induce reversible transitions between a molecular solid and an ionic liquid phase in 2D. Nonequilibrium melting dynamics are visualized by rapidly heating the graphene surface with electrical current and imaging the resulting evolution toward new equilibrium states. An analytical model has been developed that explains the observed equilibrium mixed-state phases based on direct spectroscopic measurement of solid and liquid molecular energy levels. Observed non-equilibrium melting dynamics are consistent with Monte Carlo simulations.

Rights:

• In Copyright
  

Keyword: Solid-liquid phase transitions, scanning tunneling microscopy, graphene field-effect transistor

Date published: 2023-07-13

Publisher: Wiley

Journal:

• Advanced Materials (ISSN: 15214095) vol. 35 issue. 39 2300542

Funding:

• Thomas Young Centre TYC‐101
• Engineering and Physical Sciences Research Council EP/S025324/1

Manuscript type: Publisher's version (Version of record)

MDR DOI:

First published URL: https://doi.org/10.1002/adma.202300542

Related item:

Other identifier(s):

Contact agent:

Updated at: 2025-02-23 22:49:36 +0900

Published on MDR: 2025-02-23 22:49:39 +0900