Polymer Science and Engineering Department, University of Massachusetts, Amherst, Massachusetts 01003, USA.
ACS Nano. 2009 Dec 22;3(12):4105-9. doi: 10.1021/nn901016u.
Silicon quantum dots (QDs) were prepared with a corona of di-n-octyl phosphine oxides, by performing hydrosilylation chemistry on the surface of hydrogen-terminated Si QDs. These novel Si QDs proved well-suited to serve as "ligands" for other semiconductor QDs, such as CdSe, by interaction of the phosphine oxide corona with the CdSe surface. A pronounced photoluminescence quenching of CdSe quantum dots was observed upon introduction of the phosphine oxide functionalized Si QDs to a CdSe QD solution. Surface functionalization of the Si QDs proved critically important to observing these effects, as conventional (alkane-covered) Si QD samples gave no evidence of electronic interactions with TOPO-covered CdSe. In a comparative system, phosphine oxide terminated oligo(phenylene vinylene) molecules acting as CdSe QD ligands provide a similar fluorescence quenching, with exciton decay kinetics supporting the formation of an electronically interacting hybrid materials system.
硅量子点（QDs）通过在氢封端的 Si QDs 表面进行硅氢加成反应，用二正辛基氧化膦冠制备。这些新型 Si QDs 通过氧化膦冠与 CdSe 表面的相互作用，非常适合作为其他半导体 QDs（如 CdSe）的“配体”。当将磷膦氧化物功能化的 Si QDs 引入 CdSe QD 溶液中时，观察到 CdSe 量子点的明显光致荧光猝灭。Si QDs 的表面功能化对于观察这些效应至关重要，因为常规（烷烃覆盖的）Si QD 样品没有与 TOPO 覆盖的 CdSe 发生电子相互作用的证据。在一个比较系统中，作为 CdSe QD 配体的磷膦氧化物封端的寡聚（对苯乙烯）分子提供了类似的荧光猝灭，激子衰减动力学支持形成电子相互作用的混合材料体系。
