Chemistry Commons^™

Effect Of Imidazole Ionic Liquids On The Electro-Oxidation Of P-Methoxy Toluene, Qiong Chen, Ying-Hong Zhu, Ying Zhu, Yan-Fang Li, Chun-An Ma

Journal of Electrochemistry

The interactions between four Imidazole ionic liquids (EMIMBF₄, BMIMBF₄, BMIMHSO₄, BMIMAc) and p-methoxy toluene were investigated by ultraviolet spectroscopy. The red shifts of absorption peak were obviously observed, and the fine structures of the spectroscopy were disappeared on the long wave district. p-MT producing stable excited state was benefit from the interaction with solvent molecules. The electro-oxidation behavious of p-MT were studied in the four ILs on platinum electrode by cyclic voltammetry (CV) and chronoamperometry (CP), and the diffusion coefficients (D) and activation energies (ED) were calculated. The results indicated that the electro-oxidation process …

Supramolecular Biopolymeric Composite Materials: Green Synthesis, Characterization And Applications, Tamutsiwa Moven Mututuvari

Dissertations (1934 -)

Macrocycles, such as crown ethers (CRs) and resorcinarenes (RESs), exhibit selective complexation of heavy metal ions and organic pollutants respectively. Consequently, they have been investigated for their suitability in adsorbing these aqueous pollutants. However, they are difficult to handle and recycle for reuse because, by themselves, they can only be fabricated in powder form. To alleviate this challenge, we developed a method to encapsulate these macrocycles into film-forming polysaccharides--cellulose (CEL) and chitosan (CS). This was achieved by using a green and recyclable solvent, an ionic liquid, to dissolve both macrocycles and polysaccharides and regenerate corresponding composites in water. Resultant composites …

In-Situ Afm Force Curve Investigations On Layered Structures Of Au(111)-Ionic Liquid Interfaces And Temperature Dependence, Xiao Zhang, Yun-Xin Zhong, Jia-Wei Yan, Bing-Wei Mao

Journal of Electrochemistry

By utilizing in-situ AFM force curve measurements systematic investigations have been carried out on Au(111)-ionic liquid interface in BMIPF₆ and OMIPF₆ of imidazolium-based ionic liquids with different lengths of alkyl side chains. The temperature dependence of the number, thickness and stability of the layered structures of each system are studied by performing AFM force curve measurements at potentials far negative of the PZC. The layered structures at Au (111)/BMIPF₆ interface are composed of two charged interior layers and two neutral exterior layers at -1.0 V, while those at Au (111)/OMIPF₆ interface only one charged interior layer …

Structural Dynamics And Charge Transport In Room Temperature Ionic Liquids, Philip James Griffin

Doctoral Dissertations

Room temperature ionic liquids are an important class of materials due to their chemical tunability and numerous advantageous physicochemical properties. As a result, ionic liquids are currently being investigated for use in a wide array of chemical and electrochemical applications. Despite their great potential, however, the relationship between the chemical structure and physicochemical properties of ionic liquids is not well understood.

To this end, this dissertation presents experimental studies of the reorientational structural dynamics and charge transport properties of a variety of room temperature ionic liquids using quasielastic light scattering spectroscopy and broadband dielectric spectroscopy.

Studies of a series of …

Electrochemical Behavior Of Ionic Liquid Confined Into Nanopores Of Silica Gel Matrix, Zuo-Peng Li, Ya-Qiong Wen, Mei-Xia Wu, Yong Guo

Journal of Electrochemistry

Imidazolium Ionic liquids (ILs) nano aggregates confined into nanopores of silica gel matrices (ILs-sg) modified electrodes were prepared by sol-gel process and characterized by cyclic voltammetry. Furthermore, the amounts of 15% ~ 28% ILs-sg and nano aggregates coated with ILs silica gel (ILs/sg) were prepared and their conductivities were evaluated by performing electrochemical AC impedance measurements from 20 ^oC to 80 ^oC. The abnormal results showed that, 1) comparing with the bulk IL, the confined IL had a positive shift effect of Fc/Fc+ redox potential; 2) when IL confined into a nanospace, the electrochemical stability became poor; 3) …

Underpotential Deposition Of Germanium On Au(111) And Pt(111) Surfaces In Ionic Liquids, Xu-Fen Xie, Jia-Wei Yan, Jing-Hong Liang, Ji-Jun Li, Meng Zhang, Bing-Wei Mao

Journal of Electrochemistry

The underpotential deposition (UPD) of germanium (Ge) in BMIPF₆ ionic liquids on Au(111) and Pt(111) surfaces have been investigated by cyclic voltammetry (CV) and in-situ scannin tunneling microscopy (STM). The CV results show that there are two reduction peaks related to the electrodeposition of Ge. The first reduction peak appeared in the CV curve may cover the transformation of Ge⁴⁺ to Ge²⁺ and the UPD of Ge. The second reduction peak corresponds to the bulk deposition of Ge. In-situ STM study suggests that the two UPD layers of Ge are formed on Au(111) and Pt(111) surfaces. The …

Electrochemical Performance Of Limn2O4 In Pyr14Tfsi Containing Electrolyte At 50 OC, Li-Zhen Wang, Xin-Ke Sun, Xu-Zhao Yang, Lin-Sen Zhang, Yong Zhang, Wen-Jing Zhang

Journal of Electrochemistry

In this work, with an aim to improve the performance of spinel lithium manganese and to reduce the safety concern of Li-ion battery system, the effects of N-methyl-N-butylpyrrolidinium bis (trifluoromethylsulfonyl) imide (PyR₁₄TFSI) on performance of electrolyte and spinel lithium manganes are studied by using differential scanning calorimetry (DSC), BTS battery test system, electrochemical work station, X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The results indicate that the ionic conductivity of electrolyte is increased with the increase of PyR₁₄TFSI concentration. When the concentration of PyR₁₄TFSI is 2.5% (by mass), the …