Molecular-Orientation-Dependent Interfacial Charge Transfer in Phthalocyanine/MoS2 Mixed-Dimensional Heterojunctions

Suyog Padgaonkar, Samuel H. Amsterdam, Hadallia Bergeron, Katherine Su, Tobin J. Marks, Mark C. Hersam, Emily A. Weiss

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

Mixed-dimensional heterojunctions (MDHJs) combine the characteristics of component materials such as the discrete orbital energies of zero-dimensional (0D) molecules and the extended band structure of two-dimensional (2D) semiconductors. Here, time-resolved spectroscopy reveals sub-picosecond photoinduced hole-transfer and sub-320 fs photoinduced electron-transfer processes at the interfaces of type-II copper and free-base phthalocyanine/monolayer MoS2 MDHJs. In CuPc/MoS2 heterojunctions, charge separation lasts as long as 70 ns, which is a factor of 17 longer than that in H2Pc/MoS2 heterojunctions and a factor of 40 longer than that in previously reported transition-metal dichalcogenide-based heterojunctions. Preservation of the charge-separated state is attributed to the face-on orientation of CuPc on the MoS2 surface, which templates stacking of CuPc molecules and facilitates hole migration away from the interface, whereas H2Pc molecules adopt a mixed edge-on and face-on orientation. This work highlights the role of molecular structure in determining the interfacial geometry and, ultimately, charge-transfer dynamics in 0D/2D heterojunctions.

Original languageEnglish
Pages (from-to)13337-13343
Number of pages7
JournalJournal of Physical Chemistry C
Volume123
Issue number21
DOIs
Publication statusPublished - May 30 2019

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Energy(all)
  • Physical and Theoretical Chemistry
  • Surfaces, Coatings and Films

Fingerprint Dive into the research topics of 'Molecular-Orientation-Dependent Interfacial Charge Transfer in Phthalocyanine/MoS<sub>2</sub> Mixed-Dimensional Heterojunctions'. Together they form a unique fingerprint.

  • Cite this