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Updated: Sep 25, 2025
13:56
Probe Type II Band Alignment in One-Dimensional Van Der Waals Heterostructures Using First-Principles Calculations
Published on: October 12, 2019
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HfS2/MoTe2 vdW heterostructure: bandstructure and strain engineering based on first-principles calculation
Xinge Yang1, Xiande Qin1, Junxuan Luo1
1Shenzhen Key Laboratory of Advanced Functional Material, College of Material Science and Engineering, Shenzhen University Shenzhen Guangdong 518060 China kmgu@szu.edu.cn liyu@szu.edu.cn.
RSC Advances
|May 2, 2022
Summary
This study models HfS2/MoTe2 heterostructures, revealing indirect bandgap semiconducting properties with potential for photovoltaics and UV/visible light detection. Strain can induce a semiconductor-to-metal transition and tune electronic/optical characteristics.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Van der Waals (vdW) heterostructures offer tunable electronic and optical properties.
- Layered transition metal dichalcogenides (TMDs) like MoTe2 and HfS2 are promising for electronic and optoelectronic devices.
Purpose of the Study:
- To model and simulate a multilayered HfS2/MoTe2 vdW heterostructure.
- To investigate its electronic band structure, optical properties, and response to external strain.
Main Methods:
- Density Functional Theory (DFT) calculations were employed for modeling and simulation.
- Analysis included band structure, optical spectra, and strain-induced effects.
Main Results:
- Multilayered HfS2/MoTe2 exhibits indirect bandgap semiconducting behavior (0.35–0.51 eV).
- Type-II band alignment was observed, with MoTe2 and HfS2 dominating VBM and CBM, respectively.
- Strong absorption in visible/UV regions and a semiconductor-to-metal transition under strain (critical distance 2.54 Å) were identified.
- Modulation of carrier effective mass and optical properties under strain indicates piezoelectricity.
Conclusions:
- The HfS2/MoTe2 heterostructure shows promise for photovoltaic and optoelectronic applications.
- External strain offers a pathway to tune its electronic and optical properties, highlighting its piezoelectric potential.
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