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Negative/zero thermal expansion in black phosphorus nanotubes.
1Department of Physics, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China. leiw_phy@ustb.edu.cn.
Physical Chemistry Chemical Physics : PCCP
|November 10, 2018
Summary
Black phosphorus nanotubes exhibit tunable thermal expansion, from positive to negative, by altering diameter and bonding. This controllable property is crucial for advanced nanoelectronic devices.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Black phosphorus nanotubes (BPNTs) are novel 1D materials with significant potential for nanoelectronic applications.
- Understanding thermal expansion is critical for the performance and stability of nanoelectronic devices at finite temperatures.
Purpose of the Study:
- To comprehensively investigate the thermal expansion properties of BPNTs using first-principles calculations.
- To explore the influence of structural parameters (diameter, bonding, chirality) on the thermal expansion behavior of BPNTs.
Main Methods:
- First-principles calculations were employed to simulate and analyze the thermal expansion of BPNTs.
- The study examined both armchair and zigzag BPNT configurations.
Main Results:
- BPNTs demonstrate tunable thermal expansion, ranging from positive (PTE) to zero (ZTE) and negative (NTE), by modifying diameter and bonding.
- Thermal expansion in zigzag BPNTs is diameter-independent, while armchair BPNTs show a significant size effect, allowing for easier CTE regulation.
- Unusual phonon hardening with increasing temperature was observed in both armchair and zigzag BPNTs, linked to unique dynamical modes and vibrational amplitudes.
Conclusions:
- The study reveals controllable and tunable thermal expansion in BPNTs, offering pathways for designing materials with specific thermal properties.
- Findings provide insights into abnormal thermal expansion mechanisms in nanotubes and their regulation for nanoelectronic applications.
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