Baquero Edwin A, Ojo Wilfried-Solo, Coppel Yannick, Chaudret Bruno, Urbaszek Bernhard, Nayral Céline, Delpech Fabien
LPCNO (Laboratoire de Physique et Chimie des Nano-Objets), Université de Toulouse, INSA, UPS, CNRS, 135, avenue de Rangueil, F-31077 Toulouse, France.
Laboratoire de Chimie de Coordination, UPR-CNRS 8241, 205 route de Narbonne, 31077 Toulouse Cedex, France.
Phys Chem Chem Phys. 2016 Jun 29;18(26):17330-4. doi: 10.1039/c6cp03564g.
The control and understanding of the chemical and physical properties of quantum dots (QDs) demands detailed surface characterization. However, probing the immediate interface between the inorganic core and the ligands is still a major challenge. Here we show that using cross-polarization magic angle spinning (MAS) NMR, unprecedented information can be obtained on the surface ligands of Cd3P2 and InP QDs. The resonances of fragments which are usually challenging to detect like methylene or methyl near the surface, can be observed with our approach. Moreover, ligands such as hydroxyl and ethoxide which have so far never been detected at the surface can be unambiguously identified. This NMR approach is versatile, applicable to any phosphides and highly sensitive since it remains effective for identifying quantities as low as a few percent of surface atoms.
对量子点（QD）化学和物理性质的控制与理解需要详细的表面表征。然而，探测无机核心与配体之间的直接界面仍是一项重大挑战。在此，我们表明，使用交叉极化魔角旋转（MAS）核磁共振（NMR）技术，可以获得关于Cd3P2和InP量子点表面配体的前所未有的信息。通过我们的方法，可以观察到通常难以检测的片段的共振信号，如靠近表面的亚甲基或甲基。此外，迄今为止从未在表面检测到的羟基和乙醇盐等配体也能够被明确识别。这种核磁共振方法具有通用性，适用于任何磷化物，并且高度灵敏，因为它对于识别低至百分之几的表面原子数量仍然有效。
