Anatase TiO2−x–C nanotubes demonstrate a superior Li storage capacity as high as 320(±68) mA h g−1 compared to 180(±38) mA h g−1 for TiO2−x.

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Plane sailing: Planar TiOxCy films are used as model supports for Pt nanoparticles for ethanol oxidation at 25–80 °C. The highest steady‐state current density of Pt on TiOxCy at 80 °C was a factor of 170 higher than that of Pt on glassy carbon.

Nanostructuring of electrode materials is a promising approach to enhance the performance of next-generation, high-energy density lithium (Li)-ion batteries. Various experimental and theoretical approaches allow for a detailed understanding of solid-state or surface-controlled reactions that occur in nanoscaled electrode materials. While most techniques which are suitable for nanomaterial investigations are restricted to analysis widths of the order of Å to some nm, they do not allow for characterization over the length scales of interest for electrode design, which is typically in the order of mm. In this work, three different self-organized anodic titania nanotube arrays, comprising as-grown amorphous titania nanotubes, carburized anatase titania nanotubes, and silicon coated carburized anatase titania nanotubes, have been synthesized and studied as model composite anodes for use in Li-ion batteries. Their 2D areal Li densities have been successfully reconstructed with a sub-millimeter spatial resolution over lateral electrode dimensions of 20 mm exploiting the Li(n,α)H reaction, in spite of the extremely small areal Li densities (10-20 μg cm Li) in the nanotubular active material. While the average areal Li densities recorded via triton analysis are found to be in good agreement with the electrochemically measured charges during lithiation, triton analysis revealed, for certain nanotube arrays, areas with a significantly higher Li content ('hot spots') compared to the average. In summary, the presented technique is shown to be extremely well suited for analysis of the lithiation behavior of nanostructured electrode materials with very low Li concentrations. Furthermore, identification of lithiation anomalies is easily possible, which allows for fundamental studies and thus for further advancement of nanostructured Li-ion battery electrodes.

Self‐organized anodic titania (TiO2) nanotube arrays are an interesting model anode material for use in Li‐ion batteries owing to their excellent rate capability, their cycling stability and their enhanced safety compared to graphite. A composite material where carbothermally treated conductive TiO2 nanotubes are used as support for a thin silicon film has been shown to have the additional advantage of high lithium storage capacity. This article presents a detailed comparison of the structure, surface and bulk morphology of self‐organized conductive TiO2 nanotube arrays, with and without silicon coating, using a combination of X‐ray diffraction, X‐ray reflectivity, grazing‐incidence small‐angle X‐ray scattering (GISAXS) and time‐of‐flight grazing‐incidence small‐angle neutron scattering (TOF‐GISANS) techniques. X‐ray diffraction shows that the nanotubes crystallize in the anatase structure with a preferred (004) orientation. GISAXS and TOF‐GISANS are used to study the morphology of the nanotube arrays, delivering values for the inner nanotube radius and intertubular distances with high statistical relevance because of the large probed volume. The analyses reveal the distinct signatures of a prominent lateral correlation of the TiO2 nanotubes of ∼94 nm and a nanotube radius of ∼46 nm. The porosity averaged over the entire film using TOF‐GISANS is 46%. The inner nanotube radius is reduced to half (∼23 nm) through the silicon coating, but the prominent lateral structure is preserved. Such in‐depth morphological investigations over large sample volumes are useful towards development of more efficient battery electrode morphologies.