Surface Crystallization of Liquid Au–Si and Its Impact on Catalysis. Issue 5 (5th December 2018)

• Record Type: Journal Article
• Authors: Panciera, Federico; Tersoff, Jerry; Gamalski, Andrew D.; Reuter, Mark C.; Zakharov, Dmitri; Stach, Eric A.; Hofmann, Stephan; Ross, Frances M.
• Is Part Of: Advanced materials. Volume 31:Issue 5(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-12-05
• Subjects: 2D crystals -- in situ transmission electron microscopy -- metastable phases -- nanowires -- surface ordering; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.201806544
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract: In situ transmission electron microscopy reveals that an atomically thin crystalline phase at the surface of liquid Au–Si is stable over an unexpectedly wide range of conditions. By measuring the surface structure as a function of liquid temperature and composition, a simple thermodynamic model is developed to explain the stability of the ordered phase. The presence of surface ordering plays a key role in the pathway by which the Au–Si eutectic solidifies and also dramatically affects the catalytic properties of the liquid, explaining the anomalously slow growth kinetics of Si nanowires at low temperature. A strategy to control the presence of the surface phase is discussed, using it as a tool in designing strategies for nanostructure growth. Abstract : In situ transmission electron microscopy reveals the presence of an atomically thin crystalline phase at the surface of liquid Au–Si. This surface ordering plays a key role in the pathway by which the Au–Si eutectic solidifies and also dramatically affects the catalytic properties of the liquid, explaining the anomalously slow growth kinetics of Si nanowires at low temperature.