Hexagonal boron nitride (h-BN) monolayers were grown on Pt(110) using borazine as a precursor molecule. The resulting surface structure was studied by scanning tunneling microscopy, low-energy electron diffraction, and density functional theory calculations. Borazine fragments reduce the roughening temperature of pristine Pt(110) (T r = 1090 K); consequently, growth below T = 1100 K results in a serrated h-BN/Pt(110) surface with small terraces, defects, and domain boundaries. Surprisingly, h-BN deposition at T > 1100 K yields large terraces covered by a carpet-like single-domain h-BN monolayer. Despite the incommensurability and different symmetry, the epitaxial growth is almost perfect. The key to this counterintuitive behavior is the "soft" Pt(110) surface responding to the h-BN overlayer in two ways: First, the (1 × 2)missing-row (m.r.) reconstruction is converted into a (1 × n)-m.r. reconstruction with a regular alternation of n = 5 and 6, yielding a superperiodicity of the Moirépattern. Second, the remaining rows experience significant relaxations. Some Pt surface atoms are mobile underneath the h-BN monolayer, even at room temperature. Under growth conditions, the top metal layer is disordered and highly mobile, rendering the h-BN growth comparable to that on liquid gold. Such a mechanism may be of general relevance for the epitaxial growth of 2D materials. Because epitaxial deposition of Pt(110) on various substrates has been demonstrated, the present system appears scalable, and its regular 1D grooves render it a promising template for nanowire arrays.

The electrochemical lithiation/delithiation behavior of self-organized amorphous and anatase titanium dioxide (TiO 2 ) nanotubes (NTs) is analyzed by means of electrochemical impedance spectroscopy (EIS) and X-ray photoelectron spectroscopy (XPS). The bulk lithiation properties are governed by the different phase transitions in amorphous and anatase TiO 2. While in the case of amorphous nanotubes the phase transition only leads to a thermodynamic limitation of the bulk Li content, it additionally limits the lithiation kinetics for the anatase case. This kinetic constraint is found to originate from underlithiation of the anatase TiO 2−x bulk caused by the instant first phase transition during lithium insertion. Together with the surface lithiation properties, it leads to different lithiation characteristics. Amorphous nanotubes are characterized by a reversible surface chemistry and thus pseudocapacitive lithiation/delithiation behavior. As a result, amorphous TiO 2 nanotubes show higher overall capacities due to the contribution of surface lithiation, higher capacity retention, higher rate capability, and higher Coulombic efficiencies at high C-rates, even though at the lowest applied lithiation potential of 1.1 V, slightly more lithium is inserted into the bulk of anatase TiO 2−x nanotubes under quasi steady-state conditions.

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Adsorption, desorption and fragmentation of borazine on Pt(110) are studied by temperature-programmed desorption, ultraviolet photoemission spectroscopy, workfunction measurements and density functional theory.

Sinter plant off-gas is usually de-dusted by electrostatic precipitators. Compliance with the dust emission limits is often difficult because of the high specific resistivity of the emitted dust. Mechanical properties of the dust are also relevant for the electrostatic precipitator design. Dust samples from the four consecutive electrostatic precipitator fields were characterized in this study. Most measured parameters showed a considerable variation in the various dust samples. The particle size of the dust as well as its bulk density continuously decreased from the first field to the fourth field. The flowability of the dusts was generally bad and decreased from the first to the last field. In contrast, the wall friction angles with structural steel were quite constant at approximately 30°. The Fe content was lower in the dust from the last two fields while the concentration of K, Na, Cl(-) and [Formula: see text] was significantly higher. At the same time the particle density was lower. The maximum specific dust resistivity for the first field and second field dust was approximately 3 × 10(11) Ω cm and no signs for the occurrence of back corona were detected. For the dusts from the last two fields the maximum value was approximately 2 × 10(12) Ω cm. Back corona was observed in the temperature range from 120°C to 210°C. In this area the dust resistivity values were higher than 4 × 10(11) Ω cm.