Direct imaging and identification of individual dopant atoms in MoS 2 and WS2 catalysts by aberration corrected scanning transmission electron microscopy

Francis Leonard Deepak, Rodrigo Esparza, Belsay Borges, Xochitl Lopez-Lozano, Miguel Jose-Yacaman

Research output: Contribution to journalArticlepeer-review

53 Scopus citations

Abstract

In the case of the hydrodesulfurization (HDS) processes one of the best catalysts currently available is that based on MoS2 and WS 2. A very significant increase in their activity can be achieved by adding Co or Ni as a promoter. In the present report we have used probe aberration corrected STEM (scanning transmission electron microscopy) for the first time to characterize Co doped MoS2/WS2 nanowire catalysts (supported on Al2O3 substrates). The high-resolution imaging reveals clearly the location of Co in the individual catalysts. This has not been possible to date with other experimental techniques because of the insufficient image contrast and/or resolution. On the basis of the HAADF-STEM images, we built two models for the Co-Mo-S and Co-W-S catalysts to illustrate the different morphologies found in the catalysts. With this study it is now possible to better locate, identify, and understand the role of promoters in the design and functioning of catalysts.

Original languageEnglish (US)
Pages (from-to)537-543
Number of pages7
JournalACS Catalysis
Volume1
Issue number5
DOIs
StatePublished - May 6 2011
Externally publishedYes

Keywords

  • Co doped MoS/WS nanowires
  • hydrodesulfurization (HDS)
  • MoS and WS based catalysts
  • probe aberration corrected STEM

ASJC Scopus subject areas

  • Catalysis
  • Chemistry(all)

Fingerprint

Dive into the research topics of 'Direct imaging and identification of individual dopant atoms in MoS 2 and WS2 catalysts by aberration corrected scanning transmission electron microscopy'. Together they form a unique fingerprint.

Cite this