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Porous hexagonal ordered anodic alumina (PAOX) is a longknown porous oxide material. Despite its straightforward experimental approach, a precise understanding of the microscopic processes that lead to the formation of the material and the hexagonal arrangement is only possible with the help of various theoretical models. To the best of our knowledge, there is no model that establishes a theoretical connection between the longrange order of the PAOX system and its physicochemical properties. Therefore, we present in this paper the derivation of a known key figure ("porosity number"), which makes a statement about the pore arrangement with the highest symmetry. By combining this key figure with the abstract concept of entropy production, we enable the microscopic approach to be combined with macroscopic bulk parameters. The theory is based on the most realistic assumption, that the pore habitus can be described based on the inner and outer pore volume of the PAOX cells. Herein, the former is characterized by an ion flow toward the anode and the latter by a flow toward the electrolyte bulk. In addition, the parameters required to describe PAOX growth are reduced to a minimum by showing that within our theoretical model, the growth is only controlled by migration-dependent parameters and that convection and diffusion terms are negligible.

The new 1,2‐dithiooxalato‐bridged bimetallic Cu–Ga, Cu–In, and Cu–Sn complexes [{(Ph3P)2Cu(μ‐S2C2O2)}3Ga] (1), [{(Ph3P)2Cu(μ‐S2C2O2)}3In] (2), [(Ph3P)2Cu(μ‐S2C2O2)In(S2CNEt2)2] (3), and [{(Ph3P)2Cu(μ‐S2C2O2)}2Sn(S2C2O2)] (4) were prepared and spectroscopically fully characterized. The crystal structures of 2–4 are presented. Complexes 3 and 4 are potential molecular single‐source precursors (SSP) for the ternary semiconductors CuInS2 and Cu2SnS3, respectively, which can be manipulated under ambient conditions. Indeed, a study of the thermal degradation of 3 and 4 revealed that 3 affords pure nanoscaled CuInS2 (mean diameter ca. 2 nm) when the decomposition is carried out in an oleylamine solution by using a hot‐injection or arrested‐precipitation technique at temperatures well below 250 °C. In contrast, 4 decomposes under the same reaction conditions in an ambiguous manner and forms mixed binary chalcogenide phases. This can be explained by a subtle influence of the relative stability of possible SnII and SnIV intermediates in the case of SSP [{(Ph3P)2Cu(μ‐S2C2O2)}2Sn(S2C2O2)] (4).

Surface-enhanced Raman spectroscopy (SERS) represents an important spectroscopic technique with applications in many fields due to its ability to determine structural information of the analyte with high sensitivity, which requires the design of SERS substrates with high enhancement factors. Silver-coated porous anodic alumina (PAA) membranes arise as efficient and easy-to access SERS substrates with high enhancement factors. Related barrier-type anodic alumina (BAA) has not been investigated for SERS applications so far due to an absence of porosity and the anticipation of low SERS sensitivity. Now, we have found that nonporous BAA obtained through electrolysis using periodic and iodic acid followed by sputter deposition with silver exhibits higher SERS enhancement than that of just silver deposited on PAA where the enhancement factor of the best SERS substrate based on BAA from periodic acid shows a 2.6-fold increase compared to the prepared PAA-based SERS substrate. We have shown that physically derived factors as increased surface roughness, increased refractive index, or enhancement based on interference can be excluded upon comparison of different types of BAA. Chemical characterization revealed that iodine oxoacid-derived BAA, which is employed for the first time, contains iodine ionic species pointing toward a chemical enhancement mechanism aside from the physical enhancement effect.

Boron and boron containing materials have created a new class of catalysts for the highly selective conversion of light alkanes to building block olefins. Boron oxide species seem to play an essential role for the oxidative dehydrogenation of propane. For boron nitride they are created through an induction process under reaction conditions. It is still not obvious how different kinds of oxidative pre-activation influences the observed activity and selectivity. Here we compare two different oxygen activation strategies of boron nitride, a classical activation by calcination at different temperatures and ball-milling with varying rotation velocity. These treatments allow to control the amount of introduced boron oxide species from 0.2 to 17.5 wt.-%, as quantified by alkalimetric titration. The catalytic experimental data together with the pre, post as well as in situ characterization, give insights how the catalyst's surface changes under reaction conditions. On this backdrop it can be deduced that molten boron oxide predominantly acts as catalyst under reaction conditions, and boron nitride as catalyst support.