Low-Valent Lead Hydride and Its Extreme Low-Field ¹H NMR Chemical Shift.
The use of semiconductor nanocrystal quantum dots (QDs) in optoelectronic devices typically requires postsynthetic chemical surface treatments to enhance electronic coupling between QDs and allow for efficient charge transport in QD films. Despite their importance in solar cells and infrared (IR) li...
| Publicado en: | Journal of the American Chemical Society Vol. 139; no. 19; pp. 6542 - 6546 |
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| Autores principales: | , , , , , , , , , , |
| Formato: | Artículo |
| Publicado: |
American Chemical Society
5/17/2017
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| Materias: | |
| Acceso en línea: | Ver este registro en EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=hlh&AN=123111765&site=ehost-live header: @attributes: shortDbName: hlh uiTerm: 123111765 longDbName: Humanities International Complete uiTag: AN controlInfo: bkinfo: jinfo: jid: 00027863 ACS jtl: Journal of the American Chemical Society issn: 00027863 maglogo: N pubinfo: dt: 5/17/2017 vid: 139 iid: 19 pid: 997 pub: American Chemical Society artinfo: ui: 123111765 10.1021/jacs.7b01856 ppf: 6542 ppct: 4 formats: tig: atl: Low-Valent Lead Hydride and Its Extreme Low-Field ¹H NMR Chemical Shift. aug: au: Lin, Qianglu Yun, Hyeong Jin Liu, Wenyong Song, Hyung-Jun Makarov, Nikolay S. Isaienko, Oleksandr Nakotte, Tom Chen, Gen Luo, Hongmei Klimov, Victor I. Pietryga, Jeffrey M. affil: Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States Department of Chemical and Materials Engineering, New Mexico State University, Las Cruces, New Mexico 88003, United States su: Hydrides Chemical amplification Nuclear magnetic resonance spectroscopy sug: subj: Hydrides Chemical amplification Nuclear magnetic resonance spectroscopy ab: The use of semiconductor nanocrystal quantum dots (QDs) in optoelectronic devices typically requires postsynthetic chemical surface treatments to enhance electronic coupling between QDs and allow for efficient charge transport in QD films. Despite their importance in solar cells and infrared (IR) light-emitting diodes and photodetectors, advances in these chemical treatments for lead chalcogenide (PbE; E = S, Se, Te) QDs have lagged behind those of, for instance, II-VI semiconductor QDs. Here, we introduce a method for fast and effective ligand exchange for PbE QDs in solution, resulting in QDs completely passivated by a wide range of small anionic ligands. Due to electrostatic stabilization, these QDs are readily dispersible in polar solvents, in which they form highly concentrated solutions that remain stable for months. QDs of all three Pb chalcogenides retain their photoluminescence, allowing for a detailed study of the effect of the surface ionic double layer on electronic passivation of QD surfaces, which we find can be explained using the hard/soft acid-base theory. Importantly, we prepare highly conductive films of PbS, PbSe, and PbTe QDs by directly casting from solution without further chemical treatment, as determined by field-effect transistor measurements. This method allows for precise control over the surface chemistry, and therefore the transport properties of deposited films. It also permits single-step deposition of films of unprecedented thickness via continuous processing techniques, as we demonstrate by preparing a dense, smooth, 5.3-μm-thick PbSe QD film via doctor-blading. As such, it offers important advantages over laborious layer-by-layer methods for solar cells and photodetectors, while opening the door to new possibilities in ionizing-radiation detectors. pubtype: Academic Journal doctype: Article src: R language: English refInfo: copyright: @attributes: flag: Y dt: @attributes: year: 2017 holdings: @attributes: islocal: N |
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