Acetonitrile

About: Acetonitrile is a research topic. Over the lifetime, 11298 publications have been published within this topic receiving 175275 citations. The topic is also known as: cyanomethane & ethyl nitrile.

Viscosities of Acetate or Chloride-Based Ionic Liquids and Some of Their Mixtures with Water or Other Common Solvents

Abstract: For the temperature range (80 to 120) °C, viscosity data are reported for imidazolium-based ionic liquids 1-octyl-3-methylimidazolium chloride [Omim][Cl], 1-hexyl-3-methylimidazolium chloride [Hmim][Cl], 1-butyl-3-methylimidazolium chloride [Bmim][Cl], 1-ethyl-3-methylimidazolium chloride [Emim][Cl], 1-ethyl-3-methylimidazolium acetate [Emim][Ac], 1-butyl-3-methylimidazolium acetate [Bmim][Ac], and 1-butyl-3-methylimidazolium dicyanamide [Bmim] [N(CN)2]. Acetate-based ionic liquids have considerably lower viscosities than the corresponding chloride-based ILs. At 25 °C, viscosity data are reported for binary mixtures of [Bmim][Ac] with diluents water, acetonitrile, dimethylformamide (DMF), and ethylene glycol. Even a small concentration of diluent very much reduces the viscosity of an ionic liquid.

Solubility-Induced Ordered Polythiophene Precursors for High-Performance Organic Thin-Film Transistors

Abstract: With the aim of enhancing the field-effect mobility of self-assembled regioregular poly(3-hexylthiophene), P3HT, by promoting two-dimensional molecular ordering, the organization of the P3HT in precursor solutions is transformed from random-coil conformation to ordered aggregates by adding small amounts of the non-solvent acetonitrile to the solutions prior to film formation. The ordering of the precursor in the solutions significantly increases the crystallinity of the P3HT thin films. It is found that with the appropriate acetonitrile concentration in the precursor solution, the resulting P3HT nanocrystals adopt a highly ordered molecular structure with a field-effect mobility dramatically improved by a factor of approximately 20 depending on the P3HT concentration. This improvement is due to the change in the P3HT organization in the precursor solution from random-coil conformation to an ordered aggregate structure as a result of the addition of acetonitrile. In the good solvent chloroform, the P3HT molecules are molecularly dissolved and adopt a random-coil conformation, whereas upon the addition of acetonitrile, which is a non-solvent for aromatic backbones and alkyl side chains, 1D or 2D aggregation of the P3HT molecules occurs depending on the P3HT concentration. This state minimizes the unfavorable interactions between the poorly soluble P3HT and the acetonitrile solvent, and maximizes the favorable π–π stacking interactions in the precursor solution, which improves the molecular ordering of the resulting P3HT thin film and enhances the field-effect mobility without post-treatment.

Electroreduction of oxygen in a series of room temperature ionic liquids composed of group 15-centered cations and anions

Abstract: The electrochemical reduction of oxygen is reported in four room temperature ionic liquids (RTILs) based on quaternary alkyl -onium cations and heavily fluorinated anions in which the central atom is either nitrogen or phosphorus Data were collected using cyclic voltammetry and potential step chronoamperometry at gold, platinum, and glassy carbon disk electrodes of micrometer dimension under water-free conditions at a controlled temperature Analysis via fitting to appropriate theoretical equations was then carried out to obtain kinetic and thermodynamic information pertaining to the electrochemical processes observed In the quaternary ammonium electrolytes, reduction of oxygen was found to occur reversibly to give stable superoxide, in an analogous manner to that seen in conventional aprotic solvents such as dimethyl sufoxide and acetonitrile The most significant difference is in the relative rate of diffusion; the diffusion coefficients of oxygen in the RTILs are an order of magnitude lower than in c