【作者】 陈翌庆； 张琨； 王兵； 侯建国；

【Author】 CHEN Yi-qing, ZHANG Kun, WANG Bing, HOU Jian-guo(School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009, China; Key Structure Research Laboratory, University of Science and Technology of China, Hefei 230026, China)

【机构】 合肥工业大学材料科学与工程学院； 中国科技大学结构分析重点实验室；

【摘要】 热蒸发法与溶胶-凝胶法相结合,成功制备出大量非晶SiO2纳米线.这些纳米线的直径在10-200nm范围内,长度可达几十或几百微米.借助于低温(14K)光致发光谱(PL),我们发现平均直径为150nm和15nm的非晶SiO2纳米线表现出极大的不同.前者的发光谱带可分解为峰值分别在494nm(2.51eV)和429nm(2.89eV)附近的两个蓝光发射带.而后者除了在496nm(2.5eV)有一个宽的蓝光带外,在375nm(3.32eV)、385nm(3.22eV)和395nm(3.13eV)处还表现出三个明显的紫外发光峰位.这些蓝光带的产生是由于非晶SiO2纳米线中的氧空位缺陷中心引起的。但紫外发光峰产生的原因尚需进一步研究.此外,直径为15nm的非晶SiO2纳米线的发光强度是直径为150nm的纳米线的6倍多,表现出明显的量子尺寸效应.更多还原

【Abstract】 Bulk-quantity amorphous SiO2 nanowires have been successfully synthesized by combination of sol-gel method with thermal evaporation method. These nanowires have diameters in the range of 10-200 nm, and lengths up to tens or hundreds of micrometers. The low-temperature (14K) photoluminescence (PL) spectrum of the amorphous SiO2 nanowires with a mean diameter of 150 nm and that of 15 nm are quite different. The PL spectrum of the former can be deconvoluted into two blue emission bands, a blue peak at 494 nm (2.51eV) and the other at 429 nm (2.89eV). However, the PL spectrum of the latter shows three obvious ultraviolet (UV) peaks around 375 nm (3.32eV), 385 nm (3.22eV) and 395 nm (3.13eV), besides one wide blue band near 496 nm (2.5eV). The blue emission bands could be attributed to defect centers of oxygen deficiency in amorphous SiO2 nanowires, while the origins of ultraviolet (UV) peaks in amorphous SiO2 nanowires with a mean diameter of 15 nm are unknown. Moreover, the luminescence intensity of the amorphous SiO2 nanowires with a mean diameter of 15 nm is over six times higher than that of 150 nm, which shows a obvious quantum confinement effect.更多还原