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Abstract: Gel polymer electrolytes containing 1-ethyl-3-methylimidazolium-bis (trifluoromethyl-sulfnyl)imide (EMITFSI) ionic liquid were prepared for lithium ion batteries by solution casting method. Thermal and electrochemical properties have been determined for the gel polymer electrolytes. Proper addition of EMITFSI to the P(VdF-HFP)-LiTFSI polymer electrolyte improves the ionic conductivity and electrochemical window to 2.11 × 10−3 S cm−1 (30 °C) and 4.6 V. In combination of the prepared ternary P(VdF-HFP)-LiTFSI-EMITFSI ionic liquid polymer electrolytes, Li4Ti5O12 anode exhibited two extra voltage plateaus around 1.1 V and 2.3 V except the typical voltage plateau around 1.6 V by possible side reaction between ionic liquid and polymer. LiFePO4 cathode exhibited high capacity above 140 mA h g−1 and retention of 93.1% due to the suppressed polarization effect caused by enhanced ion transport properties. The high temperature of 80 °C didn''t have significant impact on the cycling performance. [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: An environmental-friendly electrolyte of silicate and borate, which contained an addition agent of 1H-benzotriazole (BTA) with low toxicity (LD50 of 965mg/kg), was used to prepare an anodized film on AZ31B magnesium alloy under the constant current density of 1.5A/dm2 at room temperature. Effects of BTA on the properties of the anodized film were studied by scanning electron microscopy (SEM), energy dispersion spectrometry (EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), loss weight measurement, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS), respectively. The results demonstrated that anodized growth process, surface morphology, thickness, phase structure and corrosion resistance of the anodized film were strongly dependant on the BTA concentration, which might be attributed to the formation of an BTA adsorption layer on magnesium substrate surface. When the BTA concentration was 5g/L in the electrolyte, a compact and thick anodized film could provide excellent corrosion resistance for AZ31B magnesium alloy. [Copyright &y& Elsevier]

Abstract Ionically conductive polymer electrolytes represent a class of safe and environment-friendly electrolytes for next-generation alkali metal batteries. Understanding the interplay between composition-driven interfacial processes and battery performance can fundamentally inform the design of polymer electrolytes for practical applications. In this study, we fabricate lithium metal batteries based on transparent free-standing ionic liquid gel polymer electrolytes (ILGPEs) and LiFePO 4 cathodes. We develop the ILGPEs using a composite of poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP), N-methyl-N-propylpiperidinium bis(trifluoromethanesulfonyl)imide (PP13TFSI), and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). A thorough compositional optimization shows that the lithium ion conductivity of the ILGPE increases with the increase of PP13TFSI and LiTFSI, reaching maxima of 1.3 mS cm−1 at 23 °C and 5.82 mS cm−1 at 80 °C when the ILGPE contains 60 wt% PP13TFSI and 20 wt% LiTFSI. The optimized ILGPE exhibits excellent interfacial stability against the lithium metal, as signified by the stable interfacial resistance upon long-term storage. The LiFePO 4 |ILGPE|Li cells can deliver superior battery performance with a practical capacity approaching 89.5% of the theoretical capacity and capacity retention of 95.0% after 200 cycles. The formation of the electrode–electrolyte interphases takes place primarily during the initial cycles, which likely accounts for the activation period observed in LiFePO 4 |ILGPE|Li cells. Graphical abstract Image 1 Highlights • Ionic liquid gel polymer electrolytes with high ionic conductivity were prepared. • The compatibility of ILGPE-Li metal was studied under practical conditions. • Solid-state LFP cells showed remarkable discharge capacity and cycle life at RT. • The interfacial chemistry of cells was investigated as a function of cycle number. [ABSTRACT FROM AUTHOR]

In this work, a combined approach using density functional theory (DFT), molecular dynamic simulations, and electrochemical experiments was developed to study organic additives used for a cyanide-free gold electrodeposition process. When 5,5-dimethylhydantoin (DMH) is used as the complexing agent, organic additives with either imino groups or nitrogenous heterocyclic rings including polyethyleneimine (PEI), 2,2′-bipyridine, and nicotinic acid (NA) were systematically investigated. Electronic properties and orbital information of these studied additives were determined by quantum chemical calculations based on DFT. Compared to the other additives, PEI was predicted as the most promising one for the introduced DMH based gold electrodeposition. The theoretical prediction was further verified by using experimental results. In particular, the cathodic polarization of the gold electrodeposition was significantly improved in the presence of PEI. Also, the resulting gold electrodeposit shows obviously finer crystalline particles largely. In addition, molecular dynamic simulations determined that PEI molecules possess optimized adsorption behavior on the gold surface, suggesting its effectiveness to be additive in the studied cyanide-free Au-electrodeposition electrolytes. [ABSTRACT FROM AUTHOR]

Nanocrystalline Zn–Ni (grain size about 26 nm) alloy coatings were electrodeposited on carbon steel substrates in alkaline bath with 5,5′-dimethylhydantoin (DMH) as the complexing agent. The coatings with 13 wt.%–16 wt.% Ni content and the electrolyte with high current efficiency (> 85%) were achieved at the optimized parameters, i.e., Ni 2 + /(Zn 2 + + Ni 2 + ) ratio 0.32, current density 2 A·dm − 2 , temperature 50 °C and agitation speed 1000 rpm. The electrochemical behavior of the bath has been studied by cyclic voltammetry (CV), chronopotentiometry (CE) and cathodic polarization. Results show that the deposition of Zn–Ni alloys occurs at moderate overpotential and the rotation speed and bath temperature have a strong effect on cathodic polarization curves. The effects of Ni 2 + /(Zn 2 + + Ni 2 + ) ratio, current density, temperature and agitation speed on Ni content and cathode current efficiency were investigated. Studies indicate that the phase structure, grain size, microhardness and corrosion resistance of deposits are directly dependent on Ni content in deposits. The phase structure of deposits changes from a mixture of η-phase and γ-phase to single γ-phase with (411) plane orientation. Furthermore, the grain size decreases with the increase of Zn content in deposits and the increase in current density can also lead to the decrease in grain size. The increase in microhardness of deposits is strongly affected by the increase of Ni content in deposits rather than the Hall–Petch relationship. Zn–Ni alloy coatings with about 13 wt.% Ni content present best corrosion resistance and the bath has a good stability. [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]