Structure of Colloidal Quantum Dots from Dynamic Nuclear Polarization Surface Enhanced NMR Spectroscopy
- 23 October 2015
- journal article
- research article
- Published by American Chemical Society (ACS) in Journal of the American Chemical Society
- Vol. 137 (43), 13964-13971
- https://doi.org/10.1021/jacs.5b09248
Abstract
Understanding the chemistry of colloidal quantum dots (QDs) is primarily hampered by the lack of analytical methods to selectively and discriminately probe the QD core, QD surface and capping ligands. Here we present a general concept for studying a broad range of QDs such as CdSe, CdTe, InP, PbSe, PbTe, CsPbBr3, etc., capped with both organic and inorganic surface capping ligands, through dynamic nuclear polarization (DNP) surface enhanced NMR spectroscopy. DNP can enhance NMR signals by factors of 10-100, thereby reducing the measurement times by two-to-four orders of magnitude. 1D DNP enhanced spectra acquired in this way are shown to clearly distinguish QD surface atoms from those of the QD core, and environmental effects such as oxidation. Furthermore, 2D NMR correlation experiments, which were previously inconceivable for QD surfaces, are demonstrated to be readily performed with DNP and provide the bonding motifs between the QD surfaces and the capping ligands.Funding Information
- European Research Council (306733, 320860)
This publication has 49 references indexed in Scilit:
- The coordination chemistry of nanocrystal surfacesScience, 2015
- Magneto-fluorescent core-shell supernanoparticlesNature Communications, 2014
- Flexible and low-voltage integrated circuits constructed from high-performance nanocrystal transistorsNature Communications, 2012
- Solid-State NMR of Inorganic SemiconductorsTopics in current chemistry, 2011
- Solid-State NMR Study of Cysteine on Gold NanoparticlesThe Journal of Physical Chemistry C, 2010
- Quantum-dot/dopamine bioconjugates function as redox coupled assemblies for in vitro and intracellular pH sensingNature Materials, 2010
- Size- and Site-Dependent Reconstruction in CdSe QDs Evidenced by 77Se{1H} CP-MAS NMR SpectroscopyJournal of the American Chemical Society, 2010
- Prospects of Colloidal Nanocrystals for Electronic and Optoelectronic ApplicationsChemical Reviews, 2009
- Solid state NMR studies of photoluminescent cadmium chalcogenide nanoparticlesPhysical Chemistry Chemical Physics, 2006
- Solution-State NMR Studies of the Surface Structure and Dynamics of Semiconductor NanocrystalsThe Journal of Physical Chemistry B, 1998