CdSe量子点滤光片尺寸、温度依赖的光学特性

为了缩小光谱仪体积使之适用于军事卫星等领域,本文将胶体量子点作为滤光材料,研究了CdSe胶体量子点滤光片的光学特性。本文采用热注入法合成出了高质量的CdSe胶体量子点,经过对苯二胺消光处理制备成CdSe胶体量子点滤光片。利用透射电子显微镜(TEM)进行样品形貌结构的表征及粒径尺寸的测量,并分别在不同温度下进行了紫外-可见吸收测量和紫外-可见透过率测量。实验表明,在室温情况下,CdSe胶体量子点薄膜的吸收和透过率均随粒径尺寸的增加而增加;在给定粒径尺寸的情况下,CdSe胶体量子点薄膜吸收与透过率曲线的第一激子吸收峰峰位随温度升高发生红移,CdSe胶体量子点薄膜吸收曲线温度每增加10 K红移不超过1 nm,且半峰宽增加;此外,经反复实验验证CdSe胶体量子点滤光片的稳定性及可调谐特性,证实其适合作为截止滤光片。上述结果表明,CdSe胶体量子点滤光片在微型光谱仪方面具有良好的应用价值。

Size and temperature dependence of spectral transmittance for CdSe colloidal quantum dot film filters

In order to reduce the size of spectrometers and make it suitable for military satellites and other fields,we used colloidal quantum dots as filter materials to study the optical properties of CdSe colloidal quantum dot filters.The high-quality CdSe colloidal quantum dots were synthesized by an organic phase reaction method and prepared into CdSe colloidal quantum dots thin film filters after p-phenylenediamine extinction treatment.The Transmission Electron Microscope(TEM)was used to characterize the morphology and particle size of the as-prepared samples.The UV-visible absorption and UV-visible transmittance were measured at different temperatures.The results indicated that the increase in particle size caused both absorption and transmittance to increase for CdSe colloidal quantum dots thin film filters at room temperature.Under a given particle size,the absorption and transmittance of the first exciton absorption peak red shifted with the rise in temperature.The red shift of absorption curve of CdSe colloidal quantum dots thin film filters did not exceed 1nm per 10 K temperature rising and the half-width increased.In addition,the stability and tunable characteristics of the CdSe colloidal quantum dots thin film filters have been verified through repeated experiments,and it is suitable as a cut-off filter.Therefore,CdSe colloidal quantum dots thin film filters have high value in micro-spectrometers.