中国物理B ›› 2019, Vol. 28 ›› Issue (1): 13101-013101.doi: 10.1088/1674-1056/28/1/013101
• SPECIAL TOPIC—Recent advances in thermoelectric materials and devices • 上一篇 下一篇
Qiang Li(李强), Zhen-Ling Wang(王振玲), Yu-Cheng Yu(于玉城), Lan Ma(马兰), Shao-Li Yang(杨绍利), Hai-Bo Wang(王海波), Rui Zhang(张锐)
Qiang Li(李强)1, Zhen-Ling Wang(王振玲)1, Yu-Cheng Yu(于玉城)1, Lan Ma(马兰)1, Shao-Li Yang(杨绍利)1, Hai-Bo Wang(王海波)1, Rui Zhang(张锐)2
摘要:
Using the first-principles method, we predict an orthorhombic boron-carbon binary structure with space group Imm2. This structure is verified to be dynamically and mechanically stable, and possesses a cavity of 27.5 Å2 that makes it a potential molecular sieve material. The C sp2 and sp3 hybridized bonding in Imm2 BC is an important factor for its structural stability. The energy band calculations reveal that Imm2 BC is a semiconductor with a band gap of 1.3 eV and has a promising application in the electro-optic field. The lattice thermal conductivity along the crystal [100] direction at room temperature is 186 W·m-1·K-1, that is about 5 times higher than those along the [010] and [001] directions, which stems from the different group velocity along the crystal direction. Moreover, the acoustic-optical coupling is important for heat transport in Imm2 BC, and the contribution of optical phonons to lattice thermal conductivity in the [100], [010], and [001] directions is 49%, 59%, and 61%, respectively. This study gives a fundamental understanding of the structural, electronic, elastic, and heat transport properties in Imm2 BC, further enriching the family of boron-carbon binary compounds.
中图分类号: (Ab initio calculations)