Electrodeposition of aluminium and aluminium-copper alloys from a room temperature ionic liquid electrolyte containing aluminium chloride and triethylamine hydrochloride

The electrodeposition of A1 and A1-Cu binary alloys on to gold substrates from a room temperature ionic liquid electrolyte containing A1C13-EtaNHC1 was studied. The electrochemical behavior of the electrolyte and the mechanism of deposition were investigated through cyclic voltammetry （CV）, and the properties of deposits obtained were assessed by scanning electron microscopy with energy dispersive X-ray spectroscopy （SEM-EDS） and X-ray diffraction （XRD）. A1 of 70μm in thickness and an A1-Cu alloy of 30μm in thickness with 8at% copper were deposited from the electrolyte. SEM images of the deposits indicate that the A1 deposit was smooth and uniform, whereas the Al-Cu deposit was nodular. The average crystalline size, as determined by XRD patterns, was found to be （30±5） and （29±5） nm, respectively, for A1 and A1-Cu alloys. Potentiodynamic polarization （Tafel plots） and electrochemical impedance spectroscopic （EIS） measurements showed that Al-Cu alloys are more corrosion resistant than Al.

Electrodeposition of aluminum on magnesium from ionic liquid(EMIM)Br-AlCl_3

An ionic liquid was prepared by mixing AlCl3 and 1-methyl-3-ethylimidazolum bromide(EMIM)Br under dry argon atmosphere.Electrodeposition of aluminum on magnesium was conducted at 298.15 K for 1 h by the ionic liquid and the electrochemical behavior was discussed.The results show that the aluminium deposition occurs at a potential about-0.1 V.Cathode surface was analyzed by SEM,XRD and EDS.Aluminum is successfully electrodeposited on magnesium from(EMIM)Br-AlC13 ionic liquid,and the crystal grain quality of the deposit at 15 mA/cm2is ideal with the perfect boundary of crystal grain.

Influence of alkylpyridinium ionic liquids on copper electrodeposition from acidic sulfate electrolyte

The effect of two alkylpyridinium ionic liquids (py-iLs) including N-butylpyridinium hydrogen sulfate (BpyHSO4 ) and N-hexylpyridinium hydrogen sulfate (HpyHSO4 ) on the kinetics of copper electrodeposition from acidic sulfate solution was investigated by cyclic voltammetry and potentiodynamic polarization measurements. Results from cyclic voltammetry indicate that these py-iLs have a pronounced inhibiting effect on Cu2+ electroreduction and there exists a typical nucleation and growth process. Kinetic parameters such as Tafel slope, transfer coefficient and exchange current density obtained from Tafel plots, lead to the conclusion that py-iLs inhibit the charge transfer by slightly changing the copper electrodeposition mechanism through their adsorption on the cathodic surface. In addition, scanning electron microscope (SEM) and X-ray diffraction analyses reveal that the presence of these additives leads to more leveled and fine-grained cathodic deposits without changing the crystal structure of the electrodeposited copper but strongly affects the crystallographic orientation by significantly inhibiting the growth of (111), (200) and (311) planes.

Direct electrodeposition of ionic liquid-based template-free Sn Co alloy nanowires as an anode for Li-ion batteries

Sn Co alloy nanowires were successfully electrodeposited from Sn Cl2-Co Cl2-1-ethyl-3-methylimidazolium chloride(EMIC) ionic liquid without a template. The nanowires were obtained from the molar ratio of 5:40:60 for Sn Cl2(25)Co Cl2(25)EMIC at-0.55 V and showed a minimum diameter of about 50 nm and lengths of over 20 μm. The as-fabricated SnCo nanowires were about 70 nm in diameter and featured a Sn/Co weight ratio of 3.85:1, when used as an anode for a Li-ion battery, they presented respective specific capacities of 687 and 678 m Ah·g^(-1) after the first charge and discharge cycle and maintained capacities of about 654 m Ah·g^(-1) after 60 cycles and 539 m Ah·g^(-1) after 80 cycles at a current density of 300 m A·g^(-1). Both the nanowire structure and presence of elemental Co helped buffer large volume changes in the Sn anode during charging and discharging to a certain extent, thereby improving the cycling performance of the Sn anode.

Conductivities of AlCl3/Ionic Liquid Systems and Their Application in Electrodeposition of Aluminium

Solubilities and conductivities of anhydrous AlCl3 in six kinds of ionic liquids (ILs) were measured. Among the six kinds of ILs [bmim]Cl, [bmim]Br, [bmim]BF4, [bmim]PF6, [emim][EtSO4] and [bmim][HSO4], anhydrous AlCl3 could be dissolved in the first five kinds but was hardly dissolved in [bmim][HSO4]. The results showed that the nominal solubilities of AlCl3 in ILs increased in the order of [bmim][HSO4] < [bmim]PF6 < [emim][EtSO4] < [bmim]BF4 < [bmim]Cl < [bmim]Br. Conductivities of the AlCl3/ILs systems depended apparently on the nominal molar ratio of AlCl3 to ILs. The conductivities of AlCl3/[bmim]Cl, AlCl3/[bmim]Br and AlCl3/[bmim]PF6 systems had a similar tendency as a function of the nominal molar ratio, that is, as the molar ratio was increased, conductivities increased first and then decreased, with the maximum conductivity obtained at approximately 0.9:1, 1.0:1 and 0.5:1, respectively. Conductivities of the AlCl3/[bmim]BF4 exhibited a dentate change and decreased with the molar ratio of AlCl3 to [bmim]BF4 increasing in general. With the increasing of the anhydrous AlCl3 amount in [emim][EtSO4], conductivity of AlCl3/[emim][EtSO4] monotonically decreased. AlCl3/[bmim]Cl system was chosen as the electrolyte for the electrodeposition of Al. Preliminary experimental results showed that dense, adherent and homogeneous Al coatings could be electrodeposited on stainless steel by means of constant potential technique and the surface coverage was quite satisfactory.

Quantum chemical aided molecular design of ionic liquids as green electrolytes for electrodeposition of active metals

Quantum chemical calculation was used to estimate the reduction potentials of 25 organic cations and the oxidation potentials of 11 anions.This information was used to select promising cations and anions for the preparation of ionic liquids as green electrolytes for electrodeposition of active metals.The reasonable linear correlations between the lowest unoccupied molecular orbital(LUMO)energies and the reduction potentials of cations,and the linear relationships between the oxidation potentials and the highest occupied molecular orbital(HOMO)energies of anions were obtained.The orders of electrochemical stability for cations and anions being obtained agree well with the experimental measurements.The suitable ionic liquids with sufficiently wide electrochemical windows for electrodeposition of active metals are suggested to be[Emim]NTf2,[Bmim]NTf2,[Bmim]BF4, [Bmim]PF6,[Bmim]CTf3,[Emim]BF4,[Emim]PF6,[Emim]CTf3..

Gravimetric Studies of Ni Electrodeposition with Additives from Deep Eutectic Solvents Using Electrochemical Quartz Crystal Microbalance EQCM

The gravimetric analysis of electrodeposited nickel is demonstrated using electrochemical quartz crystal microbalance (EQCM) where the nickel coatings come from a solution of the metal chloride salt separately in either a1choline chloride: 2 ethylene glycol (ethaline) or 1 choline chloride: 2 urea (reline) based ionic liquid. The possibility of adapting the Quartz Crystal Microbalance EQCM (which measures the mass attached to the electrode) to probe kinetics of electrochemically-driven solid state phase transformations has been explored in a Ni electrodeposition in absence and presence of complexing agents ethylene diamine en and acetylacetonate acac from both electrolytes ethaline and reline. The study shows that the current efficiency and the rate of deposition of nickel coatings obtained from ethaline and reline baths in absence of brighteners en and acac are different, and the addition of en and acac to both ionic liquid solutions results in a significant decrease current. And the associated growth rate will also be decreased, suggesting that the en acac stops the formation and growth of Ni nuclei. This suggests that the mechanism of growth is changed.

Recycling and Activity Recovery of Chloroaluminate Ionic Liquid as Catalyst for Alkylation of Benzene with 1-Dodecene

Performances of 1-butyl-3-methylimidazolium aluminium chloride (BMIMClAlCl3) ionic liquid as catalyst for the alkylation of benzene with long chain olefins were investigated in a continuous operation mode. A small pilot plant with continuous mixingreactingseparatingrecycling functions, equipped with a static mixer reactor, a tube packed with metal Al thread and a combined liquidliquid settling phase separator, was introduced as an alternative. The results showed that the continuous fast mixing and separation of ionic liquid catalyst from reactant mixture could be synchronously accomplished within a wider flow rate ratio range of the recycling reaction mixture to the ionic liquid catalyst. The recycling of chloroaluminate ionic liquid was realized. ICPAES detection results of Al content in the reactants proves that in-situ Al compensation to the reaction system may be an important choice to prolong the stable running time of moisture-sensitive ionic liquid BMIMClAlCl3 when feedstock inevitably contains trace water. It suggests that the activity of chloroaluminate ionic liquid is recovered under the in-situ Al compensation operation.

1,3-二甲基-2-咪唑啉酮-AlCl_(3)-Cu_(2)O离子液体电沉积金属铜

为找到一种电沉积金属铜的新方法,选用1,3-二甲基-2-咪唑啉酮(DMI)、AlCl_(3)和Cu_(2)O(摩尔比为90∶10∶4)的溶剂化离子混合液体进行铜的恒电位电沉积,并分析了电解质的离子结构、电导率、黏度和密度等。拉曼光谱和核磁共振分析表明DMI-AlCl_(3)-Cu_(2)O体系中存在[AlCl2(DMI)_(4)]^(+)、AlCl_(3)(DMI)2和[AlCl_(4)]^(-)等离子团,DMI-AlCl_(3)-Cu_(2)O体系的电导率、黏度和密度随温度在323~373 K区间内呈线性变化。循环伏安研究表明,铜的起始还原电位为-0.4 V(vs Al),还原峰电位为-1.35 V;在-1.1 V至-1.4 V条件下恒电位电沉积得到金属铜,在-1.1 V和-1.4 V电位下电沉积得到的产物表面较平整,在-1.2 V和-1.3 V电位下电沉积得到的产物为纳米针状结构的铜颗粒,直径约为20~40μm。

铝在酸性AlCl_(3)-EMIC和AlCl_(3)-BMIC离子液体中的阳极溶解

1-乙基-3-甲基咪唑氯盐(EMIC)和1-丁基-3-甲基咪唑氯盐(BMIC)与氯化铝(AlCl_(3))形成的离子液体是电解铝用离子液体中最具有工业应用前景的2种离子液体。本文采用线性伏安、计时电流、计时电位、恒电压电解、恒电流电解等电化学实验方法对比搅拌和不搅拌条件下,铝在酸性AlCl_(3)-EMIC和AlCl_(3)-BMIC 2种离子液体中的阳极溶解,以筛选出较优的电解质体系,并探究搅拌、温度、电流密度、电位等工艺参数对电解过程的影响,为工业放大提供基础数据。

Electrodeposition of a dendrite-free 3D Al anode for improving cycling of an aluminum-graphite battery

Aluminum-metal batteries show great potential as next-generation energy storage due to their abundant resources and intrinsic safety.However,the crucial limitations of metallic Al anodes,such as dendrite and corrosion problems in conventional aluminum-metal batteries,remain challenging and elusive.Here,we report a novel electrodeposition strategy to prepare an optimized 3D Al anode on carbon cloth with an uniform deposition morphology,low local current density,and mitigatory volume change.The symmetrical cells with the 3D Al anode show superior stable cycling(>450 h)and low-voltage hysteresis(~170 mV)at 0.5 mA cm^(−2).High reversibility(~99.7%)is achieved for the Al plating/stripping.The graphite||Al‐4/CC full batteries show a long lifespan of 800 cycles with 54 mAh g^(−1) capacity at a high current density of 1000 mA g^(−1),benefiting from the high capacitive-controlled distribution.This study proposes a novel strategy to design 3D Al anodes for metallic-Al-based batteries by eliminating the problems of planar Al anodes and realizing the potential applications of aluminum-graphite batteries.

A gel polymer electrolyte based on IL@NH_(2)-MIL-53(Al)for high-performance all-solid-state lithium metal batteries

Solid polymer composite electrolytes possess the benefits of superior compatibility with electrodes and good thermal characteristics for more secure energy storage equipment.Herein,a new gel polymer electrolyte(GPE)containing NH_(2)-MIL-53(Al),[PP_(13)][TFSI],LiTFSI,and PVDF-HFP was prepared using a simple method of solution casting.The effects of encapsulating different ratios of ionic liquid([PP_(13)][TFSI])into the micropores of functionalized metal-organic frameworks(NH_(2)-MIL-53(Al))on the electrochemical properties were compared.XRD,SEM,nitrogen adsorption-desorption isotherms,and electrochemical measurements were conducted.This GPE demonstrates a superior ionic conductivity of 8.08×10^(-4)S·cm^(-1)at 60℃and can sustain a discharge specific capacity of 156.6 mA·h·g^(-1)at 0.2 C for over 100 cycles.This work might offer a potential approach to alleviate the solid-solid contact with the solid-state electrolyte and electrodes and broaden a new window for the creation of all-solid-state batteries.

航天用T9A-D弹簧表面离子液体镀Al工艺研究

针对弹性金属材料在表面电镀处理过程中易发生析氢现象,进而降低材料的安全稳定性,产生氢脆隐患,采用离子液体镀Al技术在T9A-D弹簧和同材质试片的表面进行改性处理,并对离子液体镀Al弹簧和试片进行形貌表征和相关性能研究。研究发现:宏观上,离子液体镀Al层连续、均匀、致密、色泽一致;微观上,Al镀层晶粒大小均匀,排列致密,无缺陷产生,截面上镀层与基体间结合良好,界面分明,无空隙,镀厚介于8.91~11.20μm,镀厚均匀。经盐雾实验测试,96 h无白色腐蚀产物出现,336 h无红色腐蚀产物出现,耐蚀性良好。经过氢含量测试,弹簧基体氢含量无增加趋势,弹簧镀Al后无氢脆倾向。弹簧镀铝前、后力值波动小于1.8 N;经划格法检测,镀Al层与弹基体间结合力良好,无脱落现象。

Constant current electrodeposition preparation of nickel layer and its mechanical properties in ionic liquid

Smooth and compact nickel layers were successfully prepared in the ionic liquid of 1-butyl-3-methylimidazolium tetrafluoroborate(BMIMBF4)by constant current electrodeposition method.The effects of temperature,additive content,current density,and deposition time on the performance of the nickel layers were systematically analyzed.Scanning electron microscopy(SEM)and X-ray diffraction(XRD)were used to analyze the surface morphology and composition of the nickel layers.Meanwhile,the tensile strengths of the nickel layers were tested by universal tensile testing machine.The results show that different process conditions have a great effect on morphology and performance of the electrodeposited nickel layer.The optimization of process parameters is as follows:BMIMBF4 to ethylene glycol(EG)volume ratio of 2:1,deposition temperature of 120℃,and current density of 1.2 mA·cm^(-2).Current density has a greater influence on the tensile strength of the nickel layer,and the maximum value of tensile strength is 1275 MPa.

Electrochemical behavior of 304 stainless steel with electrodeposited niobium as PEMFC bipolar plates

In order to enhance the corrosion resistance of 304 stainless steel, niobium was electrodeposited on its surface in air- and water-stable ionic liquids. The electrochemical behaviors of bare and niobium-coated 304 stainless steel were evaluated by electrochemical tests in a simulated proton exchange membrane fuel cell （PEMFC） environment. The results showed that niobium could be electrodeposited on the surface of 304 stainless steel from ionic liquids, and a smooth and strong chemical inert compound film was obtained on the surface of 304 stainless steel, which was mainly composed of NbO and Nb2Os. The thin composite film acted as a barrier and remarkably improved the corrosion resistance of 304 stainless steel in the PEMFC environment.

AlCl_(3)/urea类离子液体电沉积铝

类离子液体是一种新型溶剂,不仅具有离子液体独特的物理化学性能,还具有合成简单、价格低廉等优点,在电沉积铝技术方面具有广阔的应用前景。但目前相关的作用机制还未明确,从而影响类离子液体电解生产铝和电解精炼铝新工艺的开发应用。因此,本文以三氯化铝/尿素(AlCl_(3)/urea)类离子液体为电解质,利用电导率仪、黏度计、线性扫描伏安法、场发射电子扫描显微镜(FE–SEM)和X射线衍射仪(XRD)等测试手段研究了AlCl_(3)/urea类离子液体的物理化学性质、铝在电解质中的电化学行为及铝沉积产物的形貌和物相结构;系统分析AlCl_(3)/urea摩尔比和温度对体系电导率和黏度的影响,研究温度对铝离子析出电位、铝离子还原反应过程动力学、沉积铝形貌和结构的影响规律。结果表明:相同条件下,摩尔比为1.3∶1.0的AlCl_(3)/urea电解质电导率最大,黏度最小,物理化学性质较为优良,且其电导活化能为19.82 kJ·mol(–1)。升温促进了电荷迁移反应,使得金属铝的析出电位正移,交换电流密度增大,说明较高的温度有利于加快Al(Ⅲ)离子在铜基体上的还原;温度的变化对铝沉积产物的表观形貌影响不大,均由不规则的微米块体组成,但对粒径和致密性有一定影响;晶粒的生长方式也受到了温度的影响,但都具有(111)晶面优先取向。

Reinforced interface endows the lithium anode with stable cycle at high-temperature of 80℃

Embracing ultrahigh theoretical capacity of 3860 mA h g^(-1)and the lowest reduction potential of-3.04 V(versus standard hydrogen electrode),lithium(Li) is considered as the "holy grail" material for pursuing higher energy density,of which application has been challenged due to the unstable interface caused by the non-uniform electrodeposition as well as high chemical activity.Operating at higher temperature can be recommended to uniform electrodeposition of Li metal.Nevertheless,the intrinsic side-reaction between Li metal anode and electrolyte is inevitably aggravated and thus fosters the failure of Li metal anode rapidly with uneven electrodeposition.Here,a kind of temperature-tolerated ionic liquid(1-methyl-3-ethylimidazole bis(fluorosulfo nyl)imide/lithium bis(trifluoromethylsulfo nyl)imide,EF/LT)based electrolyte that matrixed with poly(vinylidene fluoride-hexafluoropropylene) was designed to maintain the interfacial stabilization of Li metal due to the weak interfacial reaction and uniform electrodeposition at high temperature of 80℃.It is the matter that the 660-h cycle with lower polarization is achieved with EF/LT-based electrolyte at temperature of 80 ℃ and the full cell embraces outstanding cyclic performance,without capacity fading within 100 cycles.Delighting,a door for practical application of Li metal anode for higher energy density as the carbon neutrality progresses in the blooming human society has been opened gradually.

Non-haloaluminate ionic liquids for low-temperature electrodeposition of rare-earth metals—A review

The inherent advantages of ionic liquids （ILs） in electrochemistry have received extensive attention in recent two decades. As a new generation of ILs, non-haloaluminate ILs exhibit better benefits and fewer drawbacks compared to haloaluminate based ILs, which are more qualified for metal electrodeposition, especially reactive metals. In this brief review, the recent developments regard- ing the application of non-haloaluminate ILs as solvents for low-temperature electrodeposition of rare-earth （RE） metals are outlined. In addition, the current problems and an outlook on future research are presented.

Electrochemical Study and Electrodeposition of Copper（I） in Ionic Liquid-reline

The authors made the electrochemical studies on the electrode processes during copper electrodeposition with ionic liquids-reline as an electrolytic medium. Reline is a commercial name for a eutectic mixture of choline chloride and urea（1：2, molar ratio）. This new proposed method of copper deposition is an ecological one because the ionic liquids are recyclable, non-volatile and non-toxic. Cyclic voltammetry investigations were conducted at 343 and 353 K in choline chloride-urea（Reline） deep eutectic solvent with single salt CuCl（generally in 0.05--0.38 mol/L concentration range）. Electrochemical impedance spectroscopy investigations were conducted in choline chloride- urea ionic liquid with CuCI（0.05 mol/L）. We investigated both cathodic and anodic processes of Cu＋ ions at different sweep rates in this new electrolytic system based on choline chloride. We have proposed by this an alternative to the classical copper electrodeposition. Coefficient of diffusion, Do, for the system Reline-CuCl is presented and the value of D0 is 1.22× 10^-8 cm2/s.

添加剂在离子液体电沉积金属及合金中的应用

近年来,基于离子液体电沉积制备金属和合金镀层已被广泛应用于多个研究领域,其电沉积过程可以克服传统水溶液体系电化学窗口窄、易受析氢副反应干扰等缺陷;相较于高温熔盐体系,离子液体可在温和条件下电沉积制备活泼金属及其合金.离子液体具有较高的黏度,导致离子迁移速率低,电沉积过程中易产生浓差极化,从而影响沉积产物的品质和性能.通过向离子液体电沉积体系中引入添加剂可以改变活性物种的电化学还原电位,进而影响晶粒的电化学结晶过程,显著改善沉积层的微观结构和性能.本文归纳总结了添加剂对离子液体中电沉积活泼金属、过渡金属和贵金属及其合金等方面的研究进展,系统分析了当前添加剂在离子液体电沉积金属及合金过程中的作用机理、效用和局限性,并展望了未来离子液体电沉积添加剂的重点研究方向.