中国物理B ›› 2023, Vol. 32 ›› Issue (5): 50505-050505.doi: 10.1088/1674-1056/acbaf0
所属专题： SPECIAL TOPIC — Smart design of materials and design of smart materials
A thermal conductivity switch via the reversible 2H-1T' phase transition in monolayer MoTe2
Dingbo Zhang(张定波)1,2, Weijun Ren(任卫君)2,3, Ke Wang(王珂)4, Shuai Chen(陈帅)2, Lifa Zhang(张力发)5, Yuxiang Ni(倪宇翔)1,†, and Gang Zhang(张刚)2,‡
- 1 School of Physical Science and Technology, Southwest Jiaotong University, Chengdu 610031, China;
2 Institute of High Performance Computing, A*STAR 138632, Singapore;
3 Center for Phononics and Thermal Energy Science, China-EU Joint Laboratory for Nanophononics, School of Physics Science and Engineering, Tongji University, Shanghai 200092, China;
4 School of Automation, Xi'an University of Posts and Telecommunications, Shaanxi 710121, China;
5 NNU-SULI Thermal Energy Research Center, and Center for Quantum Transport and Thermal Energy Science(CQTES), School of Physics and Technology, Nanjing Normal University, Nanjing 210023, China
A thermal conductivity switch via the reversible 2H-1T' phase transition in monolayer MoTe2
Dingbo Zhang(张定波)1,2, Weijun Ren(任卫君)2,3, Ke Wang(王珂)4, Shuai Chen(陈帅)2, Lifa Zhang(张力发)5, Yuxiang Ni(倪宇翔)1,†, and Gang Zhang(张刚)2,‡
- 1 School of Physical Science and Technology, Southwest Jiaotong University, Chengdu 610031, China;
2 Institute of High Performance Computing, A*STAR 138632, Singapore;
3 Center for Phononics and Thermal Energy Science, China-EU Joint Laboratory for Nanophononics, School of Physics Science and Engineering, Tongji University, Shanghai 200092, China;
4 School of Automation, Xi'an University of Posts and Telecommunications, Shaanxi 710121, China;
5 NNU-SULI Thermal Energy Research Center, and Center for Quantum Transport and Thermal Energy Science(CQTES), School of Physics and Technology, Nanjing Normal University, Nanjing 210023, China
摘要： The two-dimensional (2D) material-based thermal switch is attracting attention due to its novel applications, such as energy conversion and thermal management, in nanoscale devices. In this paper, we observed that the reversible 2H-1T' phase transition in MoTe2 is associated with about a fourfold/tenfold change in thermal conductivity along the X/Y direction by using first-principles calculations. This phenomenon can be profoundly understood by comparing the Mo-Te bonding strength between the two phases. The 2H-MoTe2 has one stronger bonding type, while 1T'-MoTe2 has three weaker types of bonds, suggesting bonding inhomogeneity in 1T'-MoTe2. Meanwhile, the bonding inhomogeneity can induce more scattering of vibration modes. The weaker bonding indicates a softer structure, resulting in lower phonon group velocity, a shorter phonon relaxation lifetime and larger Grüneisen constants. The impact caused by the 2H to 1T' phase transition in MoTe2 hinders the propagation of phonons, thereby reducing thermal conductivity. Our study describes the possibility for the provision of the MoTe2-based controllable and reversible thermal switch device.
中图分类号: (Thermodynamics)
- 05.70.-a