Formation of curved micrometer-sized single crystals

ACS Nano. 2014 May 27;8(5):4747-53. doi: 10.1021/nn5013513. Epub 2014 Apr 9.

Abstract

Crystals in nature often demonstrate curved morphologies rather than classical faceted surfaces. Inspired by biogenic curved single crystals, we demonstrate that gold single crystals exhibiting curved surfaces can be grown with no need of any fabrication steps. These single crystals grow from the confined volume of a droplet of a eutectic composition melt that forms via the dewetting of nanometric thin films. We can control their curvature by controlling the environment in which the process is carried out, including several parameters, such as the contact angle and the curvature of the drops, by changing the surface tension of the liquid drop during crystal growth. Here we present an energetic model that explains this phenomenon and predicts why and under what conditions crystals will be forced to grow with the curvature of the microdroplet even though the energetic state of a curved single crystal is very high.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biomimetics
  • Crystallization*
  • Germanium / chemistry
  • Gold / chemistry
  • Hot Temperature
  • Materials Testing
  • Microscopy, Electron, Scanning
  • Microscopy, Electron, Transmission
  • Nanotechnology / methods*
  • Oxygen / chemistry
  • Silicon / chemistry
  • Surface Properties
  • Temperature
  • Thermodynamics

Substances

  • Germanium
  • Gold
  • Oxygen
  • Silicon