Chemical vapor transport synthesis, characterization and compositional tuning of ZrSxSe2−x for optoelectronic applications

Joshua J. Fox, Saiphaneendra Bachu, Randal L. Cavalero, Robert M. Lavelle, Sean M. Oliver, Sam Yee, Patrick M. Vora, Nasim Alem, David W. Snyder

Research output: Contribution to journalArticlepeer-review

1 Scopus citations

Abstract

ZrS2, ZrSe2 and mixed alloy ZrSxSe2−x materials were achieved through chemical vapor transport. The incongruent melting system of Zr-S-Se formed crystalline layered flakes as a transport product that grew up to 2 cm in lateral size with cm-scale flakes consistently obtained for the entire compositional range exhibiting visible hexagonal features. Bulk flakes of the series ZrSxSe2−x (x = 0, 0.15, 0.3, 0.6, 1.05, 1.14, 1.51, 1.8 and 2) were analyzed through Raman spectroscopy revealing significant convolution of primary bonding modes and shifting of Raman features as a function of increasing sulfur composition. Additionally, activation of new modes not present in the pure compounds are observed as effects which result from disorder introduced into the crystal due to the random mixing of S-Se in the alloying process. Further structural characterization was performed via x-ray diffraction (XRD) on the layered flakes to evaluate the progression of layer spacing function of alloy composition which was found to range between 6.24 Å for ZrSe2 and 5.85 Å for ZrS2. Estimation of the compositional ratios of the alloy flakes through energy dispersive spectroscopy (EDS) large-area mapping verified the relation of the targeted source stoichiometry represented in the layered flakes. Atomic-resolution high angle annular dark field (HAADF)-scanning transmission electron microscopy (STEM) imaging was performed on the representative Zr(S0.5Se0.5)2 alloy to validate the 1T atomic structure and observe the arrangement of the chalcogenide columns stacks. Additionally, selected area diffraction pattern generated from the [0 0 0 1] zone axis revealed the in-plane lattice parameter to be approximately 3.715 Å.

Original languageEnglish (US)
Article number125609
JournalJournal of Crystal Growth
Volume542
DOIs
StatePublished - Jul 15 2020

All Science Journal Classification (ASJC) codes

  • Condensed Matter Physics
  • Inorganic Chemistry
  • Materials Chemistry

Fingerprint Dive into the research topics of 'Chemical vapor transport synthesis, characterization and compositional tuning of ZrS<sub>x</sub>Se<sub>2−x</sub> for optoelectronic applications'. Together they form a unique fingerprint.

Cite this