Preparation and structural properties of thin carbon films by very-high-frequency magnetron sputtering

Growth and structural properties of thin a-C films prepared by the 60 MHz very-high-frequency(VHF) magnetron sputtering were investigated. The energy and flux of ions impinging the substrate were also analyzed. It is found that the thin a-C films prepared by the 60 MHz sputtering have a lower growth rate, a smooth surface, and more sp~3 contents.These features are related to the higher ion energy and the lower ions flux onto the substrate. Therefore, the 60 MHz VHF sputtering is more suitable for the preparation of thin a-C film with more sp~3 contents.     

用聚合物金属络合物为母体制备高温超导体

采用微交联的聚丙烯酸盐为母体的方法,制备成功 YBaCuo 高温超导体,其超导性能与传统陶瓷工艺制品相近.这种工艺预烧时间短,合成单一超导相温度低.     

Rh在单壁碳纳米管上吸附的密度泛函理论研究

本文利用密度泛函理论研究了Rh原子在（6,6）单壁碳纳米管内外的吸附行为. 通过对Rh在单壁碳纳米管上不同吸附位的吸附构型与吸附能的研究发现: Rh吸附在管内、外的洞位最稳定, 且管外吸附比在管内强. 这是由于单壁碳纳米管的卷曲效应使得管外电荷密度比管内大造成的. 态密度分析表明, 吸附在管内外的Rh原子的5s电子均转移到了4d轨道上; Rh原子4d轨道上的电子转移到了（6, 6）碳管上, 使Rh带正电, 碳管带负电. 结合能带分析表明, Rh原子吸附在管内磁性较弱, 而吸附在管外较强. 关键词： 密度泛函理论 单壁碳纳米管 Rh原子 吸附     

Structural, curvature and electronic properties of Rh adsorption on armchair single-walled carbon nanotube

This paper systematically studies the rolling effects of the (n, n) single-wall carbon nanotubes (SWCNT) with different curvatures on Rh adsorption behaviours by using density functional theory. The outside charge densities of SWCNTs are found to be higher than those inside, and the differences decrease with the increase of the tube radius. This electronic property led to the discovery that the outside adsorption energies are higher than the inside ones, and that the differences are reduced with the increase of the tube radius. Partial density of states and charge density difference indicate that these strong interactions induce electron transfer between Rh atoms and SWCNTs.     

卷曲方式对Rh原子在单壁碳纳米管内外吸附的影响

碳纳米管曲率与卷曲方式是同时存在并影响金属原子在碳纳米管内外吸附行为的重要因素, 单独研究卷曲方式对金属吸附行为的影响较困难. 选取曲率相近、卷曲方式不同的扶手椅型(6, 6)、锯齿型(10, 0)与手性(8, 4)单壁碳纳米管(SWCNT), 利用密度泛函理论研究了Rh原子在SWCNT内外的吸附行为. 构型优化表明:由于SWCNT卷曲方式不同, 导致Rh原子在(6, 6),(10, 0)与(8, 4)SWCNT内外吸附的稳定构型不同; 不同卷曲方式亦使SWCNT与Rh原子相互作用的C原子不同, 导致Rh 关键词： 密度泛函理论 单壁碳纳米管 Rh原子 卷曲方式