The fabrication of nanoscopic silicon based membranes has been carried out by using a non‐expensive electrochemical preparation technique. For these purposes an n+‐silicon wafer is anodized to create oriented pores with typical diameters around 50 nm. The length of the channels is up to 50 μm which yields to an aspect ratio of 1000. The channels of these templates are partially filled with a metal, especially a ferromagnetic one to obtain an array of nanostructures. Metal‐deposition within such high aspect ratio pores is a great challenge but could be realized in some extent. The introduced silicon based nanocomposite offers the opportunity to change between different nano‐architectures by accurate adjustment of the electrochemical fabrication parameters. Also the size and spatial distribution of the precipitated metal‐structures within the pores can be varied by altering the galvanic deposition process. Different morphologies and varying metal fillings modify the physical properties (e.g. magnetic behaviour) of the nanocomposite system. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Cubic Li 7 La 3 Zr 2 O 12 (LLZO), stabilized by supervalent cations, is one of the most promising oxide electrolyte to realize inherently safe all-solid-state batteries. It is of great interest to evaluate the strategy of supervalent stabilization in similar compounds and to describe its effect on ionic bulk conductivity σ′ bulk . Here, we synthesized solid solutions of Li 7– x La 3 M 2– x Ta x O 12 with M = Hf, Sn over the full compositional range ( x = 0, 0.25...2). It turned out that Ta contents at x of 0.25 (M = Hf, LLHTO) and 0.5 (M = Sn, LLSTO) are necessary to yield phase pure cubic Li 7– x La 3 M 2– x Ta x O 12 . The maximum in total conductivity for LLHTO (2 × 10 –4 S cm –1 ) is achieved for x = 1.0; the associated activation energy is 0.46 eV. At x = 0.5 and x = 1.0, we observe two conductivity anomalies that are qualitatively in agreement with the rule of Meyer and Neldel. For LLSTO, at x = 0.75 the conductivity σ′ bulk turned out to be 7.94 × 10 –5 S cm –1 (0.46 eV); the almost monotonic decrease of ion bulk conductivity from x = 0.75 to x = 2 in this series is in line with Meyer–Neldel’s compensation behavior showing that a decrease in E a is accompanied by a decrease of the Arrhenius prefactor. Altogether, the system might serve as an attractive alternative to Al-stabilized (or Ga-stabilized) Li 7 La 3 Zr 2 O 12 as LLHTO is also anticipated to be highly stable against Li metal.

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