排序方式: 共有3条查询结果,搜索用时 51 毫秒
1
1.
基于格林函数方法及Landauer-Büttiker公式, 研究了纳米石墨带异质结的电子输运性质, 石墨带异质结由Z 形石墨带与两个锯齿型石墨带电极构成. 研究发现电导大小依赖其几何构型. 由于电子局域在锯齿型石墨带边缘, 因此在费米能级附近出现了电导隙或电导谷. 调节结间石墨带的宽度, 发现准束缚态的存在诱导许多尖锐的电导峰, 电导峰的数目几乎与结间的石墨带长度无关. 在低能区, 当θ为60°或150°时, 宽度均匀的Z型石墨带仍然保持弹道输运特征. 因此, Z形纳米石墨带可选择地应用于未来的纳微电路. 相似文献
2.
用Ti片和H2O2在较低的温度下通过控制反应时间制备了不同形貌的纳米TiO2.在80℃下反应10 min得到了和Ti片黏附较好的多孔纳米结构,延长反应时间先后得到了类花状和类棒状纳米结构.在80℃下反应4 h得到的纳米结构样品为非晶态,而反应10 h制备出以锐钛矿相为主的结晶态纳米结构.通过300℃退火得到的几乎是纯锐钛矿相的纳米TiO2.用紫外光照射降解RhB溶液的方法研究了纳米TiO2的光催化性能.结果表明7 cm2的退火后的类花状纳米TiO2降解染料分子的光催化效率是仅用紫外光降解的29.8倍. 相似文献
3.
TiO2 nanostructures were fabricated by a reaction of Ti foils in H2O2 solution at mild temperature. Porous TiO2 nanostructures, well-adhered to Ti foil surfaces, were formed at 80 ±C in 10 min, and then flower- like and rod nanostructures formed in succession after a longer reaction time. Samples prepared at 80 ±C for 4 h are amorphous, and anatase-dominated crystal phase emerged in the sample prepared for as long as 10 h. Almost pure anatase phase were obtained in TiO2 nanostructures by annealing the samples at a temperature of 300 ±C. Photocatalysis of the TiO2 nanostructures was characterized by the degradation of RhB dye molecules in an aqueous solution exposed to ultraviolet light. Results show a 7 cm2 annealed TiO2 flower-like nanostructure having the degradation rate of RhB as fast as 29.8 times that of the dye solution exposed to ultraviolet light alone. 相似文献
1