SiO₂纳米材料作为典型的纳米绝缘材料, 其量子尺寸限制效应和不同类元素独特的光电特性相结合, 在生物医药方面及纳米器件集成电子领域具有广泛应用。 随着科学时代的到来, 研究成果日益增加, 稀土掺杂纳米发光材料的研究工作逐渐展开, 其应用范围也很广阔, 如: 信息显示、 激光材料、 光纤通信、 甚至荧光探测。 Sm³⁺是一种重要的稀土氧化物离子材料, 它在太阳能电池、 纳米电子器件、 半导体玻璃、 生物化学传感器和纳米磁体等领域具有潜在应用。 本研究使用热蒸发法合成了Sm³⁺掺杂SiO₂纳米棒材料。 通过扫描电镜、 X射线衍射谱和拉曼散射光谱等手段对样品进行分析发现: Sm³⁺掺杂SiO₂纳米棒为四方相晶体; 随沉积温度降低, 纳米棒直径增大, 沉积密度减少, 样品形貌由纳米棒状结构逐渐变为微米颗粒; 由于Sm³⁺离子半径较大, 导致掺杂后SiO₂晶格衍射向小角度偏移, 晶格常数增加, 晶胞体积增大。 Sm³⁺掺杂SiO₂纳米棒的生长过程没有金属催化剂的影响。 在饱和蒸汽压和Ar气流作用下, 气态SiO₂会顺着气流方向沉积在温度不同的衬底区域上。 在高温区优先沉积成晶核, 由于腔体内残余氧气含量逐渐被消耗降低, 纳米线在生长过程中直径逐渐减小, 导致生成物顶部为针状。 我们推断在衬底生成纳米线的同时Sm³⁺替代少量Si⁴⁺进入SiO₂晶格中。 而在低沉积温度的基底上, 随着腔体内氧含量降低, 原子扩散驱动力弱, 限制一维结构的生长, 易生长出零维结构。 Sm³⁺掺杂SiO₂纳米棒的制备遵循气-固(VS)生长机制。 Sm³⁺掺杂SiO₂纳米棒的光学性能使用紫外吸收光谱、 光致发光光谱进行分析, 发现了Sm³⁺掺杂纳米材料会促进晶体结构由单斜晶相向四方晶相的转换, 进而引起UV谱中吸收带蓝移, 文中实验制备的四方结构SiO₂纳米材料紫外吸收边蓝移, 对应的带隙增大了0.7~0.8 eV。 当受到激发后, 不同于传统的无掺杂SiO₂纳/微米材料, Sm³⁺离子掺杂后SiO₂将能量传递给Sm³⁺, 材料展示出良好的Sm³⁺稀土离子特征发光性能。 该研究对SiO₂材料在光信息领域的应用具有重要指导意义。

As a typical nano-insulating material, SiO₂ nanomaterial has quantum size limitations. Combined with the unique photoelectric characteristics of different elements, the effect is widely used in biomedicine and nanodevice-integrated electronics. With the advent of the scientific era, the research results are increasing daily. The research work of rare earth-doped nano-luminescent materials is gradually launched. Its broad application scope includes information display, laser materials, optical fiber communication, and fluorescence detection. Sm³⁺ is an important rare earth oxide ion material. It has potential applications in solar cells, nanoelectronic devices, semiconductor glass, biochemical sensors, and nanomagnets. In this experiment, Sm³⁺ doped SiO₂ nanorods were successfully prepared by thermal evaporation. Characterization tests using scanning electron microscopy, X-ray diffraction, and Raman scattering spectroscopy revealed that Sm³⁺ doped SiO₂ nanorods have a tetragonal crystal structure. With the decrease of deposition temperature, the diameter of the nanorod increases, the deposition density decreases, and the morphology of the sample changes from a nanorod-like structure to a micro-particle gradually; after doping, the diffraction of the SiO₂ lattice shifts to a small angle, the lattice constant increases, and the cell volume increases. The growth process of Sm3+ doped SiO₂ nanorods was not affected by metal catalysts. Under saturated vapor pressure, gaseous SiO₂ will deposit on substrate regions with different temperatures along the direction of carrier gas flow. Regions with higher temperatures tend to deposit and nucleate preferentially. In the low-temperature region, the oxygen diffusion driving force decreases, and the nucleation growth opportunity decreases, inhibiting the growth of one-dimensional nanostructures and making it easier to form nanoparticles. The synthesis of Sm³⁺ doped SiO₂ nanorods follows a gas-solid (VS) growth mechanism. An analysis of the optical performance of Sm³⁺ doped SiO₂ nanorods by UV and PL tests found that the doping affected the light absorption of SiO₂ is blue-shifted, and the corresponding band gap is increased by 0.7~0.8 eV. Different from traditional SiO₂ nano/micron material, Sm³⁺ doped SiO₂ transferred energy to Sm³⁺ after being stimulated by radiation, and the material showed a Sm³⁺ characteristic luminescence performance. This study has important guiding significance for applying SiO₂ materials in optical information.