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The density and pore diameter of aluminum (Al) films have an important influence on the resultant film applications, especially in the field which require extremely high-density, uniform Al films. In this study, Al was electrodeposited from 1-ethyl-3-methyl imidazolium chloride ([EMIm]Cl) ionic liquid onto a Ni substrate using AlCl3 as the Al source. The results show that the concentration of the electrolyte was the crucial factor governing the microstructure of the electrodeposited continuous and dendrite-free Al film. The obtained continuous, dendrite-free Al film was used as the anode of a Li-ion battery. The obtained Al films delivered a first specific capacity reaching 1492 mAh g−1 in the Li-ion battery and effectively improved the corrosion resistance of the Ni substrate. [ABSTRACT FROM AUTHOR]

Germanium (Ge) is an important semiconductor material in optoelectronic devices and is being researched in energy storage fields. Ge nanostructure materials with different morphologies may lead to distinctly different application performances. In this work, Ge nanorod architectures were successfully template-free electrodeposited on ITO substrate from the ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide ([Emim]Tf2N) containing dissolved GeCl4 with the assistance of UV light. The UV irradiation influences the conformation of imidazolium rings of [Emim]+ adsorbed during the deposition process. A solution template has been formed on the surface of the electrode which inhibited the lateral growth of Ge nuclei and promoted the growth of Ge nanorod structures. Consequently, the coral-like Ge nanorod bundles (NRBs) has been obtained. This method provides attractive prospects for the other semiconductor nanorod structures. [ABSTRACT FROM AUTHOR]

Germanium has emerged as a promising Li ion battery anode material due to its high theoretical capacity. The in situ growth of Ge nanowires on current collectors (binder-free electrodes) has attracted much attention owing to their good electrical contact, excellent strain accommodation ability, promising material durability and short Li ion diffusion distance. Herein, we report a facile and efficient technique to synthesize Ge nanowire cluster arrays (Ge NWCAs) on nickel foam through an ultraviolet light (UV) assisted, template-free electrodeposition process from 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide ([Emim]Tf2N). As a binder-free anode material, a Ge NWCA electrode exhibits a specific capacity of 1612 mA h g−1 and retains 740 mA h g−1 up to 200 cycles at a current rate of 0.2C. The Ge NWCA electrode affords excellent rate capacity at 0.1C–2C and retains specific capacity as high as 959 mA h g−1 at 2C. Furthermore, the specific capacity well recovers to 998 mA h g−1 when the rate is reduced from 2C to 0.1C. UV assisted ionic liquid electrodeposition might open up a new avenue for the synthesis of semiconductor nanostructures. [ABSTRACT FROM AUTHOR]

Ge nanotube array anodes are prepared by template-assisted electrodeposition from an ionic liquid to obtain superior cycling performance. They show remarkable cycling ability at 0.2 C, with a very high initial discharge capacity of 1641 mA h g−1 and a charge capacity of 1260 mA h g−1. After 250 cycles the capacity retention is 98% relative to that at the 50th cycle. [ABSTRACT FROM AUTHOR]

High-capacity anode materials for lithium ion batteries (LIBs), such as Ge, generally suffer tremendous volume changes, as a result of the conversion reaction mechanism with Li, severely impede the high rate and cycling performance toward their practical application. In this article, we demonstrate a general LIBs Ge composites electrodes fabrication method using electrodeposition from room temperature ionic liquid. Our process is capable of forming composites electrodes with carbon nanotubes (CNTs), reduced graphene oxide (RGO), poly (3,4-ethylenedioxythiophene) (PEDOT), without the additives and conductive agents. During the electrodeposition process, Ge nanoparticles are integrated into the substrate network. Benefiting from the porosity, conductive network and mechanical stability constructed by interpenetrated compound layers, the hybrid system synergistically enhances the intrinsic properties of each component, yet is robust and flexible. The Ge/CNTs, Ge/RGO and Ge/PEDOT composites retain capacities of ∼851, 1212, and 1300 mAh/g after 200 cycles at 0.1 C. SEM analysis suggests that Ge/PEDOT composites have flower-like hierarchically porous structure, during cycling this structure transforms into a porous network, which can mitigate the physical strains during the Li uptake/release process, and increase the interfacial contact area with organic electrolyte. Consequently, the Ge/PEDOT composites demonstrate greatly enhanced rate capability without obvious capacity fading at high rate of up to 5 C. [ABSTRACT FROM AUTHOR]