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X-ray photoemission spectroscopy (XPS) measurements in near-ambient pressure (NAP) conditions result in a signal loss of the primary spectrum as a result of inelastic scattering of photoelectrons in the gas phase. The inelastic scattering of the primary electrons gives rise to a secondary signal that can result in additional and often unwanted features in the measured spectrum. In the present work, we derive equations that can be used to model the resulting signal and provide equations that can be used to simulate or remove the inelastic scattering signal from measured spectra. We demonstrate this process for photoemission spectra of a wide range of kinetic energies, measured from Au, Ag, and Cu, in a variety of gases (N2, He, H2, and O2). The work is supplemented with an open-source software in which the algorithms described here have been implemented and can be used to remove the gas phase inelastic scattering signal.

Es wurde ein Modellsystem realisiert, das mittels Elektronentransfer durch eine Metall-Isolator-Metall(MIM)-Struktur die Bildung eines CO2-Radikalanions von aus der Gasphase adsorbiertem Kohlendioxid induziert, welches anschliesend zu Oxalat weiterreagiert. Dieser reversible Prozess gestattet eine Studie der involvierten Elementarschritte auf atomarer Ebene. Die Oxalatspezies an der MIM-Grenzflache wurden mithilfe der Rastertunnelmikroskopie untersucht, chemisch mittels Infrarotspektroskopie identifiziert und ihre Bildung durch Dichtefunktionalrechnungen verifiziert.

The development of effective and precious‐metal‐free electrocatalysts for the oxygen evolution reaction (OER) represents a major bottleneck to unlock a renewable energy scenario based on water splitting technologies. Materials uniting the electrical conductivity of conjugated graphitic nanomaterials with the chemical regularity of metal‐organic‐framework (MOF) crystals are promising precursors for such electrocatalysts. Nanoscale integration of these two materials is challenging. A new synthesis route is developed that integrates 2D MOF nanocrystals and graphitic carbon nanolamellae into layered composites. The graphitic carrier contributes excellent charge–transport properties, and the 2D macromolecular MOF precursor provides a suitable shuttle for introducing highly dispersed metal species. Furthermore their direct chemical environment can be controlled via selection of organic linker. Thermal decomposition of 2D cobalt tetrafluoro benzene‐dicarboxylate MOF nanocrystals within such composites enables the stabilization of cobalt oxyhydroxyfluoride nanoparticles on the graphitic carrier, which display an extraordinary activity for the OER in alkaline media, with low onset overpotential (310 mVRHE) and current densities >104 mA cm−2 μmolCo−1 at an operating overpotential of 450 mV, alongside excellent operational stability. The wide compositional array of MOFs makes this synthesis approach versatile toward advanced (electro)catalysts and other functional materials for applications from sensing to energy storage and conversion.

By using a new type of lacunary tungstoselenite {Se2W29O103} (1), which contains a “defect” pentagonal {W(W)4} unit, we explored the assembly of clusters using this building block and demonstrate how this unit can give rise to gigantic nanomolecular species, using both a “one-pot” and “stepwise” synthetic assembly approach. Specifically, exploration of the one-pot synthetic parameter space lead to the discovery of {Co2.5(W3.5O14)(SeW9O33)(Se2W30O107)} (2), {CoWO(H2O)3(Se2W26O85)(Se3W30O107)2} (3), and {Ni2W2O2Cl(H2O)3(Se2W29O103) (Se3W30O107)2} (4), effectively demonstrating the potential of the {Se2W29} based building blocks, which was further extended by the isolation of a range of 3d transition metal doped tetramer family derivatives: {M2WnOm(H2O)m(Se2W29O102)4} (M = Mn, Co, Ni or Zn, n = 2, m = 4; M = Cu, n = 3, m = 5) (5 - 9). To contrast the ‘one-pot’ approach, an optimized stepwise self-assembly investigation utilizing 1 as a precursor was performed showing that the high nuclearity clusters can con...

A new family of TeIV-containing heteropolyoxometalate building blocks which consist of a {W3} top unit and one, two, and three layers of {TeW6} base units in [TeW9O33]8-, [Te2W15O54]10-, and [Te3W21O75]12-, respectively, is synthesized.