SnO2纳米粒子的溶剂热制备及光致发光性质

Solvothermal Synthesis and Photoluminescence of SnO_2 Nanoparticles

以SnCl4·5H2O为原料,乙二胺为溶剂,用溶剂热法在180℃合成了SnO2纳米粒子,用XRD和TEM对其结构和形貌进行了表征,对SnO2纳米粒子的红外谱图、漫反射谱图以及光致发光性能进行了分析,探讨了乙二胺辅助合成SnO2纳米粒子的化学原理和生长机制。结果表明,用乙二胺辅助成长法合成的SnO2纳米粒子的粒径在40nm左右,粒径分布均匀,分散性较好。SnO2纳米粒子光致发光在340、432和672nm处有3个强峰,在472和540nm处有2个弱峰,其中340nm处的峰为紫外近带边激子发射峰,432、472和540nm处的峰是由氧缺陷引起的,672nm处的峰归因于表面态的氧缺陷引起的能带中深能级跃迁。

SnO2 nanoparticles were synthesized at 180 ℃ using SnCl4·5H2O as the starting material and ethylenediamine as solvent. The synthesized products were characterized by XRD, TEM, IR, diffuse reflectance spectrum and room-temperature photoluminescence （PL） spectrum. Chemistry and growth mechanisms of SnO2 nanoparticles by ethylenediamine-assisted synthesis were discussed. The SnO2 nanoparticles by hydrothermal synthesis in the presence of organic amines are spherical with uniform size distribution. The fluorescence spectrum of SnO2 nanoparticles shows that there are three strong emission peaks at 340,432 and 672 nm and two weak emission peaks at 472 nm and 540 nm. The PL peak at 340 nm can be attributed to ultraviolet exciton emission near band edge. The other peaks observed at 432,472 nm and 540 nm are assigned to oxygen vacancies. The red emission at 672 nm arises from transitions coming from deep level bandgap due to surface states associated with oxygen vacancies.