X-Ray Diffraction Study of Carbon Nanotubes Under High Pressure

• 来源期刊: 中国物理快报（英文版）
• 学科: 物理学
• 年，卷（期）: 2001,（4）
• 所属期刊栏目: CONDENSED MATTER：STRUCTURE，MECHANICAL AND THERMA
• 页码范围: 577-578
• 页数: 2页
• 分类号: O4
• 语种: 英文

摘要

The structure and physical properties of carbon nanotubes have been investigated by using in situ high pressureenergy dispersive x-ray diffraction with synchrotron radiation at pressures up to 50.7 Gpa. At atmosphericpressure, the structure of carbon nanotubes is similar to the hexagonal close-packed lattice of graphite with theinterplanar spacing of the diffraction line (002) d002 = 0.3404nm and that of the line (100) d100 = 0.2116nm.According to the high pressure x-ray diffraction results, the diffraction line (002) is broadened and weakenedabove 8 Gpa, and carbon nanotubes become partly amorphous. When the pressures of 10 and 20 Gpa aredecreased to zero, the diffraction line (002) is partly recovered. While at the maximum pressure of 50.7 Gpa,they become entirely amorphous and this amorphous transition is irreversible. We used the equation of state ofBirch-Murnaghan to fit the P-V data of carbon nanotubes and obtained the bulk modulus K0 = 54.3 ± 3.2 Gpa(at K1o = 4.0).C