In this work, the deposition of carbon nanowalls (CNWs) by inductively coupled plasma enhanced chemical vapor deposition (ICP-PECVD) is investigated. The CNWs are electrically conducting and show a large specific surface area, which is a key characteristic to make them interesting for sensors, catalytic applications or energy-storage systems. It was recently discovered that CNW films can be deposited by the use of the single-source metal-organic precursor aluminium acetylacetonate. This precursor is relatively unknown in combination with the ICP-PECVD deposition method in literature and, thus, based on our previous publication is further investigated in this work to better understand the influence of the various deposition parameters on the growth. Silicon, stainless steel, nickel and copper are used as substrate materials. The CNWs deposited are characterized by scanning electron microscopy (SEM), Raman spectroscopy and Auger electron spectroscopy (AES). The combination of bias voltage, the temperature of the substrate and the substrate material had a strong influence on the morphology of the graphitic carbon nanowall structures. With regard to these results, a first growth model for the deposition of CNWs by ICP-PECVD and aluminium acetylacetonate is proposed. This model explains the formation of four different morphologies (nanorods as well as thorny, straight and curled CNWs) by taking the surface diffusion into account. The surface diffusion depends on the particle energies and the substrate material and thus explains the influence of these parameters.

We present a method to fit Raman spectra of TiO2 thin films on silicon wafers, fused silica, and crown glass with adjustable model spectra of the different components of the substrate and the thin film. With reasonable restrictions of the fitting parameters, the method developed in this paper allows a simultaneous fit to the measured spectra. The TiO2 thin film spectrum is split into one spectrum for the amorphous phase and spectra for each crystalline phase (anatase, rutile, and brookite) being divided into first‐order scattering and a phase background (including second‐order scattering). Moreover, if the substrate is luminescent, the substrate spectrum is split into luminescence and Raman spectra. All decisions on parameters are made by the fitting procedure within a simultaneous fit of a series of spectral models to the observed Raman spectrum. The main strategies for preparing such models are pointed out in a way that they should be applicable to other materials. TiO2 is a promising and flexible material for photocatalytic applications with rapidly growing interest in mixed‐phase TiO2 as nanostructured material or thin film. For the analysis of such films, it is important to differentiate the signals of the various phases and to distinguish between signals from the substrate and the film. This provides a means to improve the quantitative evaluation of Raman spectra.

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The back cover image, by Sebastian Schipporeit et al., is based on the Research Article Spectral decomposition of Raman spectra of mixed‐phase TiO2 thin films on Si and silicate substrates, https://doi.org/10.1002/jrs.5369.