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Updated: Jan 18, 2026
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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Compositional design rules for tuning functionalities in CuInP2X6 (X = S, Se) van der Waals semiconductor
Mona Layegh1, Joseph W Bennett1
1Department of Chemistry & Biochemistry, University of Maryland Baltimore County, Baltimore, MD 21250, USA. bennettj@umbc.edu.
Dalton Transactions (Cambridge, England : 2003)
|September 10, 2025
Summary
Researchers explored atom substitution in 2D ferroelectrics like CuInP2Se6 (CIPSe) and CuInP2S6 (CIPS). They found specific doping strategies can tune electronic properties and polarization for new nanoscale devices.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Solid State Chemistry
Background:
- Two-dimensional van der Waals (2D-vdW) semiconducting ferroelectrics offer potential for advanced electronic devices.
- A limited selection of functional 2D-vdW ferroics necessitates the development of design principles for new materials.
Purpose of the Study:
- To investigate the effects of isovalent atom substitution on the structural, polarization, and electronic properties of CIPSe and CIPS.
- To establish design rules for engineering 2D ferroelectrics with tunable band gaps and polarization.
Main Methods:
- First-principles density functional theory (DFT) calculations were employed.
- Isovalent substitutions were systematically studied at Indium (In) and Phosphorus (P) sites in CIPSe and CIPS.
Main Results:
- Bi doping in CIPSe at In sites increased the band gap to ~1.07 eV without compromising polarization, if arranged in a zigzag pattern.
- P-site substitution in CIPSe caused significant distortions, potentially leading to metallic behavior with larger dopants.
- As doping in CIPS maintained polarization stability while decreasing the band gap, with minimal structural impact.
Conclusions:
- Atomistic substitution offers a viable route to engineer 2D ferroelectric properties.
- Dopant size, location, host lattice stiffness, and chemical compatibility are key factors in designing new 2D ferroelectrics.
- This work provides structure-property design rules for tuning polarization and band gap simultaneously in 2D ferroelectrics.
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