10402-16-1Relevant articles and documents
Kahlenberg, L.
, p. 1 - 14 (1902)
Efficient solid-state light-emitting CuCdS nanocrystals synthesized in air
Khan, Ali Hossain,Dalui, Amit,Mukherjee, Soham,Segre, Carlo U.,Sarma,Acharya, Somobrata
, p. 2643 - 2648 (2015)
Semiconductor nanocrystals (NCs) possess high photoluminescence (PL) typically in the solution phase. In contrary, PL rapidly quenches in the solid state. Efficient solid state luminescence can be achieved by inducing a large Stokes shift. Here we report on a novel synthesis of compositionally controlled CuCdS NCs in air avoiding the usual complexity of using inert atmosphere. These NCs show long-range color tunability over the entire visible range with a remarkable Stokes shift up to about 1.25 eV. Overcoating the NCs leads to a high solid-state PL quantum yield (QY) of ca. 55% measured by using an integrating sphere. Unique charge carrier recombination mechanisms have been recognized from the NCs, which are correlated to the internal NC structure probed by using extended X-ray absorption fine structure (EXAFS) spectroscopy. EXAFS measurements show a Cu-rich surface and Cd-rich interior with 46% CuI being randomly distributed within 84% of the NC volume creating additional transition states for PL. Color-tunable solid-state luminescence remains stable in air enabling fabrication of light-emitting diodes (LEDs).
Martin, A. R.,Hermann, R. N.
, p. 30 - 38 (1941)
Cu-Fe-S Nanocrystals Exhibiting Tunable Localized Surface Plasmon Resonance in the Visible to NIR Spectral Ranges
Gabka, Grzegorz,Bujak, Piotr,Ostrowski, Andrzej,Tomaszewski, Waldemar,Lisowski, Wojciech,Sobczak, Janusz W.,Pron, Adam
, p. 6660 - 6669 (2016)
Cu-Fe-S nanocrystals exhibiting a strong localized surface plasmon resonance (LSPR) effect were synthesized for the first time. The elaborated reproducible preparation procedure involved copper(II) oleate, iron(III) stearate, and sulfur powder dissolved in oleylamine (OLA) as precursors. The wavelength of the plasmonic resonance maximum could be tuned by changing the Cu/Fe ratio in the resulting nanocrystals, being the most energetic for the 1:1 ratio (486 nm) and undergoing a bathochromic shift to ca. 1200 nm with an increase to 6:1. LSPR could also be observed in nanocrystals prepared from the same metal precursors and sulfur powder dissolved in 1-octadecene (ODE), provided that the sulfur precursor was taken in excess. Detailed analysis of the reaction mixture by chromatographic techniques, supplemented by mass spectrometry and 1H NMR spectroscopy enabled the identification of the true chemical nature of the sulfur precursor in S/OLA, namely, (C18H35NH3+)(C18H35NH-S8-), a reactive product of the reduction of elemental sulfur by the amine groups of OLA. In the case of the S/ODE precursor, the true precursors are much less reactive primary or secondary thioethers and dialkyl polysulfides.
Rhodium-Catalyzed Alkenylation of Toluene Using 1-Pentene: Regioselectivity to Generate Precursors for Bicyclic Compounds
Liebov, Nichole S.,Zhu, Weihao,Chen, Junqi,Webster-Gardiner, Michael S.,Schinski, William L.,Gunnoe, T. Brent
supporting information, p. 3844 - 3851 (2019/10/16)
Rhodium catalysts for arene alkenylation reported by our group (e.g., Science 2015, 348, 421; J. Am. Chem. Soc. 2017, 139, 5474; J. Am. Chem. Soc. 2018, 140, 17007) have demonstrated selectivity for 1-aryl alkenes over y-aryl alkenes (y > 1). This selectivity is notable because 1-aryl alkenes or 1-aryl alkanes cannot be generated using acid-based Friedel-Crafts arene alkylation or acidic zeolite catalysts. Herein, we report the extension of Rh arene alkenylation catalysis to generate 1-tolyl-1-pentenes, which are potential precursors for bicyclic compounds. The olefin concentration, copper(II) oxidant identity and concentration, reaction temperature, and rhodium concentration for the alkenylation of toluene with 1-pentene have been optimized using [Rh(Η2-C2H4)2(μ-OAc)]2 as the catalyst precursor. The rhodium-based catalysis achieves up to 12(1):1 anti-Markovnikov selectivity for 1-tolyl-1-pentenes over 2-tolyl-2-pentenes and is selective for alkenylation in the meta and para positions.
