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Updated: Apr 16, 2026
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Exfoliation and Analysis of Large-area, Air-Sensitive Two-Dimensional Materials
Published on: January 5, 2019
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Temperature dependent phonon shifts in few-layer black phosphorus.
1Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Babha Road, Pune 411008, Maharashtra State, India.
ACS Applied Materials & Interfaces
|March 3, 2015
Summary
Researchers studied temperature effects on black phosphorus nanosheets, finding phonon modes soften with increasing temperature. This behavior, linked to a double resonance process, is key for understanding 2D materials in nanoelectronics.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Atomically thin two-dimensional (2D) black phosphorus (BP) shows promise for nanoelectronic and photonic devices.
- Understanding material properties under varying conditions is crucial for device development.
Purpose of the Study:
- Investigate temperature-dependent phonon shifts in few-layer black phosphorus nanosheets.
- Analyze the impact of temperature on Raman spectra to understand material behavior.
Main Methods:
- Micromechanical exfoliation of black phosphorus on a SiO2/Si substrate.
- Temperature-dependent Raman spectroscopy from 77 K to 673 K.
Main Results:
- Observed softening of Ag(1), B2g, and Ag(2) phonon modes with increasing temperature.
- Determined temperature coefficients for Ag(1), B2g, and Ag(2) modes: -0.01, -0.013, and -0.014 cm(-1) K(-1).
Conclusions:
- Temperature-dependent softening is attributed to an active double resonance process in thin samples.
- Findings are relevant for other 2D materials and heterostructures in advanced applications.
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