Zhang Z Y, Wu X L, Xu L L, Shen J C, Siu G G, Chu Paul K
National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093, People's Republic of China.
J Chem Phys. 2008 Oct 28;129(16):164702. doi: 10.1063/1.2993164.
Amorphous twisted SiO(2) nanobelts have been synthesized on Si wafers using facile thermal evaporation. These nanobelts are produced together with SiO(2) nanowires and a small quantity of SiO(2) nanosprings. Spectral and microstructural analyses suggest that the twisted SiO(2) nanobelts and nanosprings form via a polar surface driven process. Spontaneous polarization on the very thin polar crystalline SiO(2) layers on the amorphous SiO(2) nanobelt and nanospring surfaces makes the nuclei rearrange orderly and causes the nanobelt and nanowire to roll up at a certain twisty angle. The cathodoluminescence spectrum acquired from these SiO(2) nanostructures reveals three emission bands at 4.4, 3.7, and 2.7 eV originating from oxygen-related defect centers. The polar surface driven mechanism can adequately explain the growth of these novel twisty nanobelts and nanosprings which have potential applications in sensors, transducers, resonators, and photonics.
通过简便的热蒸发法在硅片上合成了非晶态扭曲二氧化硅纳米带。这些纳米带与二氧化硅纳米线以及少量二氧化硅纳米弹簧一同生成。光谱和微观结构分析表明，扭曲的二氧化硅纳米带和纳米弹簧是通过极性表面驱动过程形成的。非晶态二氧化硅纳米带和纳米弹簧表面极薄的极性晶体二氧化硅层上的自发极化使得原子核有序重排，并导致纳米带和纳米线以一定的扭曲角度卷曲。从这些二氧化硅纳米结构获得的阴极发光光谱显示出在4.4、3.7和2.7电子伏特处有三个发射带，源于与氧相关的缺陷中心。极性表面驱动机制能够充分解释这些新型扭曲纳米带和纳米弹簧的生长，它们在传感器、换能器、谐振器和光子学方面具有潜在应用。
