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Abstract: Gel-type polymer electrolytes with 1-butyl-4-methylpyridinium bis(trifluoromethanesulfonyl)imide (B4MePyTFSI) ionic liquid are formed by the solution casting method. The conductivity and transference number measurements are carried out to investigate conductivity and charge transport in the gel polymer electrolytes. The conductivity of the samples increases when the amount of B4MePyTFSI ionic liquid is increased. The lithium ion ionic conductivity reaches the maximum value (2.01×10−4 S cm−1) when GPE contains 33.3 wt% B4MePyTFSI. The electrochemical stability window of ILGPE is about 5.5V versus Li+/Li at 20°C, meeting the basic requirement of rechargeable lithium batteries. Discharge performance of lithium battery using this ILGPE membrane shows a capacity of about 160 mAh g−1. The excellent performance with higher capacity, good cycle stability and compatibility are observed for the Li/ILGPE/LiFePO4 cells. The interfacial resistances between ILGPE and electrodes have the less change after 10 cycles. [Copyright &y& Elsevier]

Abstract: Ionic liquid gel polymer electrolyte (ILGPE) based on N-methyl-N-butylpiperidinium-bis(trifluoromethanesulfonyl)imide (PP14TFSI), bis(trifluoromethanesulfonyl)imide lithium salt (LiTFSI) and poly(vinylidene difluoride-co-hexafluoropropylene) (P(VdF-HFP)) is prepared for lithium ion batteries by solution casting. The ILGPE is characterized by scanning electron microscopy (SEM), thermogravimetry (TG) and electrochemical tests. The results indicate that the addition of PP14TFSI to the P(VdF-HFP)–LiTFSI polymer electrolyte leads to 3-dimensional network structures, and the ILGPE is stable below 150°C and will not decompose until 310°C without considering the volatilizing of the residual solvent. The ionic conductivity increases with the temperature rising, and the ionic conductivity is 0.23×10−3 Scm−1 and 2.1×10−3 Scm−1 at 20°C and 80°C, respectively. The electrochemical window is −0.15 to 4.85V vs. Li+/Li, which is wide enough to be used with common electrode materials. Battery tests show that the ILGPE is stable even at 80°C when operated in Li/LiFePO4 batteries, and Li/LiFePO4 batteries with the gel polymer electrolyte exhibit good cycling performance at 60°C at 1C current rate. The discharge capacity was 131.01mAhg−1 after 100 cycles with 90% capacity retention. [Copyright &y& Elsevier]

BMIm-OTF (1-Butyl-3-methylimidazolium trifluoromethanesulfonate) ionic liquid and alcohols/different volume fraction of n -propyl alcohol (normal propyl alcohol) mixed electrolytes are studied for the first time. The electrochemical behaviors of CIGS are investigated by cyclic voltammetry (CV) in ionic liquid and alcohols mixed electrolytes, respectively. The morphological properties of CIGS films are detected using scanning electron microscopy (SEM). Raman spectra at around 175 cm − 1 are normalized to the dominant A 1 mode. The structural properties and various phases are determined by using X-ray diffraction (XRD) and Raman techniques. The XRD results indicate that the CIGS phase formed by incorporating Ga into the CIS phase. The Cu 1.00 In 0.45 Ga 0.1 Se 2.26 thin films present as a p-type semiconductor and the Ga/(Ga + In) = 0.18 which electrodeposited from BMIm-OTF/ n -propyl alcohol (30 vol%) mixed electrolytes. The band gap of the obtained CIGS thin film is approximately 1.48 eV, as measured using UV–visible absorption spectra. The carrier concentration and average Hall coefficient of the CIGS thin films are 6.366 × 10 19 cm − 3 and 9.806 × 10 − 2 cm 3 /C, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Gel polymer electrolytes containing N-butyl-N-methylpyrrolidinum bis(trifluoromethanesulfonyl) imide (PYR14TFSI) ionic liquid are prepared by the solution casting method. Thermal and electrochemical properties have been determined for these gel polymer electrolytes. The electrical properties are investigated in detail by the linear sweep voltammetry, cyclic voltammetry and impedance spectroscopy with the aid of the equivalent circuit fitting of the impedance spectra. The results show that the studied electrolytes have good self-standing characteristics, and also a sufficient level of thermal stability and a good electrochemical window. The conductivity increases with increasing amount of mixture, and for the studied system, the highest value of the conductivity measured at room temperature is 4.0×10−4 Scm−1. The lithium ions transference number reaches the maximum value when the gel electrolyte contains 33.3wt% PYR14TFSI ionic liquid. Based on the experiments, measurements and fitting, the models describing the lithium ion transmission and the properties of electrolyte/electrode interface are developed. [Copyright &y& Elsevier]

Abstract: The electrodeposition of metallic cobalt from a 1-butyl-3-methylimidazolium tetrafluoroborate ionic liquid was investigated. The electrochemical behavior of Co(II) in the ionic liquid on a platinum working electrode at 60°C was studied by cyclic voltammetry and chronoamperometry. The results from the cyclic voltammetry showed that the electrodeposition of metallic Co in the ionic liquid was an irreversible process and controlled by the diffusion of Co(II) on a platinum working electrode. The average value of αn α was calculated to be 0.35 and the diffusion coefficient (D 0) of Co(II) was calculated to be 1.76×10−8 cm2/s at 60°C. Chronoamperometric results indicated that the electrodeposition of Co on a platinum working electrode followed the mechanism of instantaneous nucleation and three-dimensional growth with diffusion-controlled. The cobalt plating was uniform, dense, shining in appearance with good adhesion to the platinum substrate at 60°C. The scanning electron microscope (SEM) micrographs were used to confirm that the cobalt plating was denser and finer at 60°C. Energy dispersive X-ray analysis (EDAX) profile showed that the obtained plating was pure cobalt. X-ray diffraction (XRD) pattern indicated that there was a preferred orientation direction and the average size of cobalt grains was 40nm. [Copyright &y& Elsevier]

In order to replace the highly poisonous cyanide zincate process of Al alloy, an eco-friendly approach was developed, i.e., electrodeposition of Cu-Zn coating from ionic liquid/ethanol mixed bath. It was demonstrated that the Cu 5 Zn 8 alloy produced from 1-ethyl-3-methylimidazolium trifluoromethylsulfonate (EMImTfO) and 20% (Volume percent) ethanol mixtures under optimal conditions showed cauliflower-shaped structure with a (330) preferred orientation, which could significantly improve the corrosion resistance of Al substrate in Watts bath, thereby elevating Ni coating quality. The overall property of Cu-Zn intermediate layer and its subsequent coating, including compactness, adhesive strength and corrosion resistance is approximately the same as that of cyanide zincate layer and its surface coating, suggesting that the new method is an ideal alternative to conventional zincate treatment. • Cu-Zn coating is electrodeposited from EMImTfO ionic liquid/ethanol mixtures. • Its overall property is approximately the same as that of cyanide zincate layer. • A high-quality Ni coating can be obtained on Cu-Zn coating from Watts bath. • It also has similar property to the Ni coating deposited on cyanide zincate layer. • This method has the great potential to replace cyanide zincate process of Al alloy. [ABSTRACT FROM AUTHOR]

Three-dimensional ordered macroporous (3DOM) CuIn x Ga 1−x Se 2 (CIGS) film is synthesized by one-step galvanostatic electrodeposition based on polystyrene templates from a special mixture of ionic liquid 1-butyl-3-methylimidazolium tetra-fluoroborate and ethanol. X-ray diffraction pattern, Raman spectroscopy and transmission electron microscopy present the CIGS film has ideal chalcopyrite crystallization. 3DOM CIGS film with high Ga content has photochemical activity and good photo-stability, its band gap is 1.34 eV. This is a simple, feasible and additive free method without selenization process to synthesize 3DOM CIGS film, the film is qualified and available for absorber-layer fabrication or other fields. [ABSTRACT FROM AUTHOR]

Stoichiometric Cu 1.00 In 0.51 Ga 0.1 Se 2.04 (CIGS) thin films containing Cu(II), In(III), Ga(III) and Se(IV) are obtained for the first time in ionic liquid/n-propyl alcohol mixtures with controlled pulse electrodeposition parameters at 323 K. The effects of deposition current density, deposition time, frequency and duty cycle are studied in detail. The band gap of obtained CuIn x Ga 1− x Se 2 (CIGS) thin film are approximately 1.35 eV, as measured using UV–visible absorption spectra. The interplanar spacing and average Hall coefficient of the CIGS thin films are approximately 3.315 Å and 1.011×10 −1 cm 3 /C, respectively. [ABSTRACT FROM AUTHOR]

Highlights: [•] Method of radical polymerization is used to prepare electrolytes. [•] PP14TFSI+LiTFSI+PMMA electrolytes have good electrochemical properties. [•] Conductivity of 6.8×10−4 Scm−1 and of 0.37 are achieve at room temperature. [•] XPS show passivating film comprises multilayer films: Li2O and Li2CO3 layer. [•] Model describing Li electrode/electrolyte interface are developed. [ABSTRACT FROM AUTHOR]