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采用高温微乳液的化学方法,在溶液中合成了高产率的CdSe四脚状纳米晶粒。高分辨透射电镜(HRTEM)分析结果表明,CdSe四脚状纳米晶粒是由1个立方的核心和4个六方的臂所组成。研究了该四脚晶粒的变激发功率光荧光(PL)谱和变温的PL谱,分析发现低温时四脚晶粒的光荧光主要来自于被表面缺陷所局域的激子的辐射复合,而随着温度升高,束缚激子被热激发,室温时光荧光主要来自于自由激子的贡献。CdSe纳米量子点的退局域化温度比四脚纳米晶粒的高,而12K时CdSe纳米量子点的局域化能量比四脚纳米晶粒的也大得多,并对这一现象作了解释。
The high-temperature microemulsion chemical method was used to synthesize CdSe tetrapod-like nanocrystals with high yield in solution. High-resolution transmission electron microscopy (HRTEM) analysis showed that CdSe tetrapod-like nanocrystals are composed of one cubic core and four hexagonal arms. Fluorescence (PL) spectra and PL spectra of varying temperature were studied. It was found that the light fluorescence of four-limbed grains mainly originated from the radiation recombination of excitons localized by surface defects at low temperature. As the temperature increases, bound excitons are thermally excited, and the fluorescence at room temperature mainly comes from the contribution of free excitons. The annealing temperature of CdSe nanometer quantum dots is higher than that of tetrapod nanocrystals, and the localization energy of CdSe nanometer quantum dots is much larger than that of tetrapod nanocrystals at 12K, and this phenomenon is made Explanation.