About: Tetraoctylammonium bromide is a(n) research topic. Over the lifetime, 219 publication(s) have been published within this topic receiving 7289 citation(s).
23 Oct 2001-Journal of Physical Chemistry B
Abstract: Noble metal particles of Au, Pt, and Ir were deposited on nanostructured TiO2 film using an electrophoretic approach. The nanocomposite films were characterized by UV-absorption and atomic force microscopy (AFM). The deposition of tetraoctylammonium bromide (TOAB)-capped metal nanoparticles on TiO2 films improved the photocurrent generation and induced a shift in the apparent flat band potential. The TiO2 films modified with TOAB-capped metal nanoparticles were less prone to the electron scavenging by the oxygen in solution. Improved photoelectrochemical performance of semiconductor−metal composite film is attributed to the shift in quasi-Fermi level of the composite to more negative potentials. Continuous irradiation of the composite films over a long period causes photocurrent to decrease as the semiconductor−metal interface undergoes chemical changes. The role of semiconductor−metal composite films in improving the rate of photocatalytic degradation of an azo dye is also discussed.
14 Mar 1997-Journal of Molecular Catalysis A-chemical
Abstract: Oxidation of dibenzothiophene with hydrogen peroxide using phosphotungstic acid as catalyst and tetraoctylammonium bromide as phase transfer agent in a mixture of water and toluene has been studied. Catalysed decomposition of hydrogen peroxide competes with dibenzothiophene oxidation but by choice of suitable conditions yields of dibenzothiophene sulphone approaching 100% may be obtained. Treatment of gas oils with this technology shows that all the sulphur compounds present are oxidised by this catalyst system and highly substituted dibenzothiophenes are the most readily oxidised of species containing a thiophene nucleus. Oxidised sulphur compounds can be separated from the oil by adsorption on silica gel. The use of oxidation and adsorption in a process for desulphurisation of gas oils is discussed.
05 Mar 2003-Journal of Physical Chemistry B
Abstract: A simple method is proposed to control the size of alkanethiol-protected Au nanoparticles by heat treatment in the solid state. The mean diameter of the Au nanoparticles prepared by Brust's two-phase method (∼1.5 nm) was evolved to 3.4−9.7 nm by heating to 150−250 °C in air. The uniform growth of nanoparticles was not observed when tetraoctylammonium bromide (TOAB), which was used as a phase-transfer agent during the preparation of Au nanoparticles, was removed before the particle growth process. The crystal structures of Au nanoparticles and alkanethiol ligand structures on Au nanoparticles were characterized before and after the heat treatment. The size-evolution mechanism was discussed on the basis of the thermodynamic model. The heat-treated Au nanoparticles easily formed self-assembled 2D superlattices with hexagonal packing, where the alkanethiol protective agents with an all-trans conformation were estimated to interpenetrate each other.
01 Jul 2018-Advanced Materials
TL;DR: A room-temperature triple-ligand surface engineering strategy to play the synergistic role of short ligands of tetraoctylammonium bromide, DDAB, and octanoic acid toward "ideal" perovskite QDs results in the highly efficient QD-based LEDs (QLEDs).
Abstract: Developing low-cost and high-quality quantum dots (QDs) or nanocrystals (NCs) and their corresponding efficient light-emitting diodes (LEDs) is crucial for the next-generation ultra-high-definition flexible displays. Here, there is a report on a room-temperature triple-ligand surface engineering strategy to play the synergistic role of short ligands of tetraoctylammonium bromide (TOAB), didodecyldimethylammonium bromide (DDAB), and octanoic acid (OTAc) toward "ideal" perovskite QDs with a high photoluminescence quantum yield (PLQY) of >90%, unity radiative decay in its intrinsic channel, stable ink characteristics, and effective charge injection and transportation in QD films, resulting in the highly efficient QD-based LEDs (QLEDs). Furthermore, the QD films with less nonradiative recombination centers exhibit improved PL properties with a PLQY of 61% through dopant engineering in A-site. The robustness of such properties is demonstrated by the fabrication of green electroluminescent LEDs based on CsPbBr3 QDs with the peak external quantum efficiency (EQE) of 11.6%, and the corresponding peak internal quantum efficiency (IQE) and power efficiency are 52.2% and 44.65 lm W-1 , respectively, which are the most-efficient perovskite QLEDs with colloidal CsPbBr3 QDs as emitters up to now. These results demonstrate that the as-obtained QD inks have a wide range application in future high-definition QD displays and high-quality lightings.
23 Mar 2011-Chemistry of Materials
Abstract: We report a facile, one-pot method for synthesizing atomically monodisperse Au144(SR)60 nanoclusters under ambient conditions. In this method, gold salt precursor is first mixed with excess thiol and tetraoctylammonium bromide (TOABr) in methanol to form Au(I)-SR polymers. Then, Au(I)-SR is reduced by excess NaBH4 (aqueous solution) to form nanoclusters. Interestingly, the initially formed, polydisperse Au nanoparticles are size-focused into two monodisperse gold nanoclusters: Au144(SR)60 (major product) and Au25(SR)18 (side product) over a ∼5 h period. The side product (Au25(SR)18) can be easily removed by washing the product with acetone, giving rise to pure Au144(SR)60. This method is applicable to a number of thiol ligands, including PhC2H4SH and various CnH2n+1SH (where n = 4−8). Some critical parameters to obtain pure Au144(SR)60 have been identified, including the methanol solvent (as opposed to toluene traditionally used), large thiol-to-Au ratios (≥4), the presence of O2 and tetraoctylammonium ha...