Dynamics of GeSbTe phase-change nanoparticles deposited on graphene

Bin Chen, Van Lam Do, George Palasantzas, Petra Rudolf, Bart J. Kooi*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

4 Citations (Scopus)

Abstract

Phase-change Ge2Sb2Te5 nanoparticles (NPs), that are promising for next-generation phase-change memory and other emerging optoelectronic applications, have been deposited on graphene support layers and analyzed using advanced transmission electron microscopy techniques allowing high quality atomic resolution imaging at accelerating voltages as low as 40 kV. The deposition results in about three times higher NP coverage on suspended graphene than on graphene containing an amorphous background support. We attribute this to the variation in surface energy of suspended and supported graphene, indicating that the former harvests NPs more effectively. Hydrocarbon contamination on the graphene profoundly enhances the mobility of the NP atoms and after prolonged (weeks) exposure to air resulted in more severe oxidation and spreading of NPs on the suspended graphene than on supported graphene because the network of hydrocarbons develops more extensively on the suspended rather than on the supported graphene. Due to this oxidation, GeOx shells are formed out of NPs having a uniform composition initially. The present work provides new insights into the structure and stability of phase-change NPs, graphene and their combinations.

Original languageEnglish
Article number505706
Number of pages10
JournalNanotechnology
Volume29
Issue number50
DOIs
Publication statusPublished - 14-Dec-2018

Keywords

  • GeSbTe
  • nanoparticles
  • graphene
  • transmission electron microscopy
  • energy dispersive x-ray spectroscopy
  • LITHIUM-ION BATTERIES
  • CRYSTALLIZATION KINETICS
  • ULTRAFAST CALORIMETRY
  • CHANGE MEMORY
  • SINGLE-LAYER
  • ENERGY
  • PERFORMANCE
  • CATALYST
  • SUPPORT
  • STORAGE

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