无膦溶剂制备带隙可调谐ZnS1-xSex量子点

Phosphine-free Synthesis of Alloyed ZnS1-xSex Quantum Dots with Tunable Bandgap Emissions

本文利用将硒(Se)粉直接置于十八烯(ODE)溶剂搅拌形成悬浮液获得Se前驱体(ODE-Se)代替传统的三丁基膦-硒(TBP-Se),制备无镉(Cd)的硒硫锌(ZnS1-xSex)合金量子点。紫外可见吸收光谱及发光光谱测试表明,当ODE-S:ODE-Se由7:3逐渐减少到0:10时,其吸收边由350 nm红移到420 nm,激子发光峰位从378 nm红移到429nm,表明通过调节前驱体比例成功实现了对ZnS1-xSex量子点能带的调控。另外,为了理解ODE-Se与传统TBP-Se的差异,分别用这两种前驱体制备了纯ZnSe量子点。研究结果表明,相比于三丁基膦-硒(TBP-Se),利用ODE-Se为Se前驱体制备的ZnSe量子点尺寸更大并分布更宽,证明ODE-Se的活性强于TBP-Se。

In this paper, the ODE-Se, instead of the traditional TBP-Se as Se precursor, was firstly used to prepare cadmium-free ZnS1-xSex alloyed quantum dots （QDs）. UV-Vis optical absorption and photoluminescence spectra were used to characterize the QDs. It was found that the absorption edge exhibit a red shift from 350 to 420 nm, while the exciton emission peak shifted from 378 to 429 nm, when the ratio of ODE -S ： ODE -Se decreases from 7：3 to 0.10. The experimental results suggested that the energy gap of the ZnS1-xSex QDs could be successfully adjusted by tailoring the precursor ratios of ODE-S to ODE-Se. To clarify the difference between ODE-Se and ODE-Se on the growth of the QDs, pure ZnSe QDs were synthesized by using these two kind Se precursors as mentioned above. The experimental results indicated that, as compared to TBP-Se, ZnSe QDs could have larger sizes and wider size distribution with ODE-Se as the Se precursor, which could be attributed to the higher activity of ODE-Se than that of TBP-Se.