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Updated: Jun 3, 2026
04:57
Residue-Free Fabrication of van der Waals Heterostructures of Two-Dimensional Materials
Published on: July 18, 2025
Stacking-Polarity-Controlled Interlayer Photocarrier Dynamics in MoSe2/MoS2 Heterostructures.
Gbenga S Agunbiade1, Ting Zheng1, Hui Zhao1
1Department of Physics and Astronomy, The University of Kansas, Lawrence, Kansas 66045, United States.
Nano Letters
|June 2, 2026
Summary
Stacking polarity offers a new way to control photocarrier dynamics in molybdenum diselenide/molybdenum disulfide (MoSe2/MoS2) heterostructures. This discovery enables precise tuning for advanced optoelectronic applications.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Optoelectronic applications of van der Waals heterostructures depend on controlling photocarrier dynamics.
- Current tuning strategies for these dynamics are limited in determinism and spatial uniformity.
Purpose of the Study:
- To investigate stacking polarity as a global control parameter for photocarrier dynamics in MoSe2/MoS2 heterostructures.
- To resolve stacking-dependent interlayer charge-transfer dynamics and interlayer exciton lifetimes.
Main Methods:
- Ultrafast pump-probe spectroscopy was employed to study MoSe2/MoS2 heterostructures.
- Hexagonal (2H) and rhombohedral (3R) MoS2 bilayers were compared, with engineered interface terminations in 3R stacking.
Main Results:
- Charge transfer in 2H heterostructures was faster than experimental resolution.
- 3R heterostructures exhibited time-resolvable charge transfer, slowing from 0.25 to 0.37 ps based on stacking polarity.
- Interlayer exciton lifetimes were tuned from approximately 40 ps to 160 ps.
Conclusions:
- Stacking polarity serves as a global control parameter for photocarrier dynamics in MoSe2/MoS2 heterostructures.
- Stacking-induced layer polarization in 3R MoS2 modulates interfacial wave function overlap, influencing charge transfer and exciton dynamics.
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