Dye-sensitized solar cells with solvent-free ionic liquid electrolytes

We systematically studied the temperature-dependent physicochemical properties, such as density, conductivity, and fluidity, of 1,3-dialkylimidazolium iodides. In combination with the amphiphilic Z907Na sensitizer, we have found that it is important to use low-viscosity iodide melts with small cations to achieve high-efficiency dye-sensitized solar cells. By employing high-fluidity eutectic-based melts the device efficiencies considerably increased compared to those for cells with the corresponding state of the art ionic liquid electrolytes.

Properties of poly(sodium 4-styrenesulfonate)-ionic liquid composite film and its application in the determination of trace metals combined with bismuth film electrode

A new kind of bismuth film modified electrode to sensitively detect trace metal ions based on incorporating highly conductive ionic liquids 1-butyl-3-methyl-imidazolium hexafluorophosphate (BMIMPF6) in solid matrices at glassy carbon (GC) was investigated. Poly(sodium 4-styrenesulfonate) (PSS), silica, and Nafion were selected as the solid matrices. The electrochemical properties of the mixed films modified GC were evaluated. The electron transfer rate of Fe(CN)(6)(4-)/Fe(CN)(6)(3-) can be effectively improved at the PSS-BMIMPF6 modified GC.

Topological Diversity of Coordination Polymers Containing the Rigid Terephthalate and a Flexible N,N'-Type Ligand: Interpenetration, Polyrotaxane, and Polythreading

Reactions of zinc(II) or cadmium(II) salts with terephthalic acid (H(2)tp) and 1,3-bis(4-pyridyl) propane (bpp) have afforded four coordination polymers at room temperature, [Zn(mu-tp)(mu-bpp)](n)center dot 2nH(2)O (1), [Cd-2(mu-tp)(2)(mu-bpp)(3)](n)center dot 2nH(2)O (2), [Cd(mu-tp)(mu-bpp)(H2O)](n)center dot nH(2)O (3), and [Cd-2(mu-tp)(mu-bpp)(2)(bpp)(2)Br-2](n) (4). Single-crystal X-ray diffraction has revealed interesting topological features for these compounds.

Phase Behavior and self-assembly of poly[N-vinylformamide-co-(acrylic acid)] copolymers under highly acidic conditions

Copolymers of N-vinylformamide and acrylic acid were synthesized by conventional aqueous free-radical polymerization. The phase behavior of the copolymer solutions was investigated through the addition of hydrochloric acid and the variation of the temperature. With a moderate content of N-vinylformamide, the copolymers showed complex phase behaviors. Under low-acidity conditions, a suspending liquid was formed, whereas under high-acidity conditions, the random copolymers could assemble into round nanoparticles with a broad particle size distribution.

Separation of ethyl acetate-ethanol azeotropic mixture using hydrophilic ionic liquids

The separation of ethyl acetate and ethanol (EtOH) is important but difficult due to their close boiling points and formation of an azeotropic mixture. The separation of the azeotropic mixture of ethyl acetate and EtOH using the hydrophilic ionic liquids (ILs) 1-alkyl-3-methylimidazolium chloride (alkyl = butyl, hexyl, and octyl) ([C(n)mim]Cl, n = 4, 6, 8) and 1-allyl-3-methylimidazolium chloride and bromide ([Amim]Cl and [Amim]Br) has been investigated. Triangle phase diagrams of five ILs with ethyl acetate and EtOH were constructed, and the biphasic regions were found as follows: [Amim]Cl > [Amim]Br > [C(4)mim]Cl > [C(6)mim]Cl > [C(8)mim]Cl. The mechanisms of the ILs including cation, anion, and polarity effect were discussed.

The solid-liquid extraction of yttrium from rare earths by solvent (ionic liquid) impreganated resin coupled with complexing method

A kind of solvent (ionic liquid) impreganated resin (IL-SIR) was developed herein for ameliorating imidazolium-type IL-based liquid-liquid extraction of metal ions. In this study, [C(8)mim][PF6] containing Cyanex923 was immobilized on XAD-7 resin for solid-liquid extraction of rare earth (RE). The solid-liquid extraction contributed to ameliorating mass transfer efficiency, i.e. shortening equilibrium time from 40 min to 20 min, increasing extraction efficiency from 29% to 80%. In additional, the novel IL-SIR could separate Y(III) from Sc(III), Ho(III), Er(III), Yb(III) effectively by adding water-soluble complexing agent.

Characterization and electrocatalytic application of a fullerene/ionic-liquid composite

A fullerene/ionic-liquid composite was explored. Transmission Electron Microscopy (TEM) study showed that in the composite, C-60 mainly exists as nano-clusters, Raman spectrum proved that the composite formed only by physical Mix of C-60 and 1-Butyl-3-methyl-imidazolium hexafluorophosphate (BMIPF6), the combination did not change the chemical naturation of C-60. The electrochemical properties of the composite modified electrode, including the electrode reaction control function and the interfacial potential effect were studied.

Ion-Responsive Behavior of Ionic-Liquid Surfactant Aggregates with Applications in Controlled Release and Emulsification

We propose a simple but efficient, rapid, and quantitative ion-responsive micelle system based on counter-anion exchange of a surfactant with an imidazolium unit. The ion-exchange reaction results in the amphiphilic-to-hydrophobic transition of the imidazolium salt, leading to the destruction of the micelles, which has been successfully applied to control led release and emulsification.

Preparation of ferrite MFe2O4 (M = Co, Ni) ribbons with nanoporous structure and their magnetic properties

Spinel ferrite, MFe2O4 (M = Co, Ni), ribbons with nanoporous structure were prepared by electrospinning combined with sol-gel technology. The ribbons were formed through the agglomeration of magnetic nanoparticles with PVP as the structure directing template. The length of the polycrystalline ribbons can reach millimeters, and the width of the ribbons can be tuned from several micrometers to several hundred nanometers by changing the concentration of precursor. The nanoporous structure was formed during the decomposition of PVP and inorganic salts.

Reversed micellar solubilization extraction and separation of thorium(IV) from rare earth(III) by primary amine N1923 in ionic liquid

The extraction behavior of thorium(IV) sulfate by primary amine N1923 in imidazolium-based ionic liquid (IL) namely 1-octyl-3-methylimidazolium hexafluorophosphate ([C(8)mim]PF6) was systematically studied in this paper. Results showed that the extraction behavior was quite different from that using conventional solvent as diluent. A reversed micellar solubilization extraction mechanism was proposed for the extraction of thorium(IV) by N1923/[C(8)mim]PF6 via slope analysis method and polarized optical microscopy (POM)/transmission electron microscopy (TEM) observation. The salt-out agent, Na2SO4, was demonstrated to prompt this extraction mechanism.

The separation of Cerium(IV) from nitric acid solutions containing Thorium(IV) and Lanthanides(III) using pure [C(8)mim]PF6 as extracting phase

The extraction behavior of Ce(IV) along with Th(IV) and Ln(III) (Ln = Ce, Gd, Yb) nitrate by pure ionic liquid, [C(8)mim]PF6, was investigated. [C(8)mim]PF6 alone showed good extraction ability for Ce(IV), while it was slight for Th(IV) and negligible for Ln(III). The extraction behavior of Ce(IV) by [C(8)mim]PF6 was particularly studied, and the most probable extraction mechanism proposed was the anion exchange mechanism. Moreover, the stripping of Ce(IV) from IL phase was also investigated. The Ce(IV) in IL phase can be quantitatively recovered by water.

Strings of interconnected hollow carbon nanoparticles with porous shells prepared using simple solid-phase synthesis

Strings of interconnected hollow carbon nanoparticles with porous shells were prepared by simple heat-treatments of a mixture of resorcinol-formaldehyde gel and transition-metal salts. The sample was characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction and nitrogen adsorption. Results show that the sample consisted of relatively uniform hollow particles with sizes ranging from 70 to 80 nm forming a strings-of-pearls-like nanostructure. The material with porous shells possessed well-developed graphitic structure with an interlayer (d(002)) spacing of 0.3369 nm and the stack height of the graphite crystallites of 9 nm.

Synthesis of Tributylphosphate Capped Luminescent Rare Earth Phosphate Nanocrystals in an Ionic Liquid Microemulsion

Uniform rare earth phosphate (REPO4, RE = La-Tb) nanocrystals were successfully synthesized in a properly designed TBP/[Omim]Cl/H2O (tributylphosphate/1-octyl-3-methyl-imidazolium chloride/water) microemulsion system. The phosphoryl groups anchored the TBP molecules oil the surfaces of the nanocrystals, and this made the nanocrystals easily dispersed in some imidazolium-based ILs. LaPO4:Eu3+ and CePO4:Tb3+ nanocrystals capped with TBP showed bright red and green emission under UV excitation, with enhanced emission intensity and lifetimes compared with the uncapped ones.

Silica Materials Doped with Bifunctional Ionic Liquid Extractant for Yttrium Extraction

Two new silica-based organic-inorganic hybrid materials (B104SGs and O104SGs) doped with a binary mixture of imidazolium and phosphonium ionic liquids have been synthesized and used as sorbents in batch system for rare earths (RE) separation. Imidazolium ionic liquids 1-butyl-3-methylimidazolium hexafluorophosphate (C(4)mim(+)PF(6)(-)) or 1-octyl-3-methylimidazolium hexafluorophosphate (C(8)mim(+)PF(6)(-)) acted as porogens to prepare porous materials and additives to stabilize extractant within silica gel.

Phase Diagram of [Amim]Cl plus Salt Aqueous Biphasic Systems and Its Application for [Amim]Cl Recovery

In this study, binodal curves and tie line data of [Amim]Cl + salt (K3PO4, K2HPO4, K2CO3) + water aqueous biphasic systems (ABS) were measured and correlated satisfactorily with the Merchuk equation and Othmer-Tobias and Bancroft equations, respectively. [Amim]Cl could be recovered from aqueous solutions using the ABS, and the recovery efficiency could reach 96.80%. The recovery efficiency was influenced by the concentrations of the salts and their Homeister series: K3PO4 > K2HPO4 > K2CO3. Our method provides a new and effective route for the recovery of hydrophilic IL using [Amim]Cl + salt + water ABS from aqueous solutions.