Electronic, Thermoelectric and Optical Properties of MoTe2 and M2CO2 (M= Ti, Zr and Hf) Monolayers and Their van der Waals Heterostructures

Micro and Nanostructures, Journal Year: 2025, Volume and Issue: unknown, P. 208190 - 208190

Published: April 1, 2025

Language: Английский

Understanding the Ultralow Thermal Conductivity and Strong Anharmonicity of a Lanthanum-Based Germanium Halide Monolayer for Possible Thermoelectric Applications

ACS Applied Energy Materials, Journal Year: 2024, Volume and Issue: 7(20), P. 9279 - 9288

Published: Oct. 11, 2024

Low-dimensional materials outperform their bulk equivalents in terms of thermal and electronic charge transport phenomena. Ultralow conductivity thermoelectric (TE) semiconductors is rare plays a crucial role obtaining promising TE performances. Their performance can be effectively improved via strain engineering, which allows the modulation geometrical parameters as well energy levels material. With this concept mind, we systematically studied effect biaxial tensile on structure, stability, mechanics, properties novel La2GeI2 monolayer by using hybrid density functional theory solving Boltzmann equations. The strain-induced distortion manipulates band characteristics with an increase gap, effective mass, relaxation time carriers. In principle, La2Ge metal, while functionalized structure becomes semiconductor. Two temperature-dependent adsorption structures have been reported experiments R3̅m phase most stable ground-state structure. HSE06 calculations predict indirect gap 0.69 eV appearing at Γ–M symmetry points Brillion zone monolayer. La–Ge bands being prominent around Fermi level emerge out p–d covalent hybridization, providing edge to enhanced conductivities. calculated coefficients (kl) seem better than those available two-dimensional such phosphorene, arsenene, etc. We find that significantly low kl value (3.22 W/mK) 300 K reduced ultralow 0.57 W/mK under strain. Owing strain-engineered conductivity, small significant Seebeck coefficient (∼1100 μV/K), ZT(∼2), rule conversion potentials comparison traditional materials.

Language: Английский

Ternary transition-metal nitride halide monolayers MNI (M = Zr, Hf) with low thermal conductivity and high thermoelectric figure of merit

Computational Materials Science, Journal Year: 2024, Volume and Issue: 247, P. 113508 - 113508

Published: Nov. 16, 2024

Language: Английский