Mesoporous GeO/Ge/C as a Highly Reversible Anode Material with High Specific Capacity for Lithium-Ion Batteries.

Nanostructured Ge is considered a highly promising material for Li-ion battery applications as Ge offers high specific capacity and Li-ion diffusivity, while inherent mesoporous nanostructures can contribute resistance against capacity fading as typically induced by high volume expansion in bulk Ge films. Mesoporous GeO/Ge/C films are synthesized using KGe Zintl clusters as a Ge precursor and the amphiphilic diblock copolymer polystyrene--polyethylene oxide as a templating tool. As compared to a reference sample without post-treatment, enhanced surface-to-volume ratios are achieved through post-treatment with a poor-good azeotrope solvent mixture.

Amphiphilic diblock copolymer-mediated structure control in nanoporous germanium-based thin films.

Fabrication of porous, foam-like germanium-based (Ge-based) nanostructures is achieved with the use of the amphiphilic diblock copolymer polystyrene-b-polyethylene oxide as structure directing agent. Basic concepts of block copolymer assisted sol-gel synthesis are successfully realized based on the [Ge9]4- Zintl clusters as a precursor for Ge-based thin films. Material/elemental composition and crystalline Ge-based phases are investigated via X-ray photoelectron spectroscopy and X-ray diffraction measurements, respectively.

N-Heterocyclic Carbene Coinage Metal Complexes of the Germanium-Rich Metalloid Clusters [Ge₉R₃] and [Ge₉R₂]² with R = Si(Pr)₃ and R = Si(TMS)₃.

We report on the synthesis of novel coinage metal NHC (-heterocyclic carbene) compounds of the germanium-rich metalloid clusters [Ge₉R₃] and [Ge₉R₂]² with R = Si(Pr)₃ and R = Si(TMS)₃. NHCCu{η³Ge₉R₃} with R = Si(Pr)₃ () represents a less bulky silyl group-substituted derivative of the known analogous compounds with R = Si(Bu)₃ or Si(TMS)₃. The coordination of the [NHCCu]⁺ moiety to the cluster unit occurs via one triangular face of the tri-capped trigonal prismatic [Ge₉] cluster.