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A software package for the calibration and processing of powder X-ray diffraction and small-angle X-ray scattering data is presented. It provides a multitude of data processing and visualization tools as well as a command-line scripting interface for on-the-fly processing and the incorporation of complex data treatment tasks. Customizable processing chains permit the execution of many data processing steps to convert a single image or a batch of raw twodimensional data into meaningful data and one-dimensional diffractograms. The processed data files contain the full data provenance of each process applied to the data. The calibration routines can run automatically even for high energies and also for large detector tilt angles. Some of the functionalities are highlighted by specific use cases.

Ni-rich layered oxides, like NCM-811, are promising lithium-ion battery cathode materials for applications such as electric vehicles. However, pronounced capacity fading, especially at high voltages, still lead to a limited cycle life, whereby the underlying degradation mechanisms, e.g. whether they are detrimental reactions in the bulk or at the surface, are still controversially discussed. Here, we investigate the capacity fading of NCM-811/graphite full-cells over 1000 cycles by a combination of in situ synchrotron X-ray powder diffraction, impedance spectroscopy, and X-ray photoelectron spectroscopy. In order to focus on the NCM-811 material, we excluded Li loss at the anode by pre-lithiating the graphite. We were able to find a quantitative correlation between NCM-811 lattice parameters and capacity fading. Our results prove that there are no considerable changes in the bulk structure, which could be responsible for the observed ≈20% capacity loss over the 1000 cycles. However, we identified the formation of a resistive surface layer, which is responsible for (i) an irreversible loss of capacity due to the material lost for its formation, and (ii) for a considerable impedance growth. Further evidence is provided that the surface layer is gradually formed around the primary NCM-811 particles.

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High-energy Li1.17Ni0.19Co0.10Mn0.54O2 (HE-NCM) is a lithium-rich layered oxide with alternating Li- and transition-metal (TM) layers in which excess lithium ions replace transition metals in the host structure. HE-NCM offers a capacity roughly 50 mAh g–1 higher compared to that of conventional layered oxides but suffers from capacity loss and voltage fade upon cycling. Differential capacity plots (taken over 100 cycles) show that the origin of the fading phenomenon is a bulk issue rather than a surface degradation. Although previous studies indicate only minor changes in the bulk material, long duration in situ synchrotron X-ray powder diffraction measurements, in combination with difference Fourier analysis of the data, revealed an irreversible transition-metal motion within the host structure. The extensive work provides new insights into the fading mechanism of the material.

Replacement of Hg with non-toxic Au based catalysts for industrial hydrochlorination of acetylene to vinyl chloride is urgently required. However Au catalysts suffer from progressive deactivation caused by auto-reduction of Au(I) and Au(III) active sites and irreversible aggregation of Au(0) inactive sites. Here we show from synchrotron X-ray absorption, STEM imaging and DFT modelling that the availability of ceria(110) surface renders Au(0)/Au(I) as active pairs. Thus, Au(0) is directly involved in the catalysis. Owing to the strong mediating properties of Ce(IV)/Ce(III) with one electron complementary redox coupling reactions, the ceria promotion to Au catalysts gives enhanced activity and stability. Total pre-reduction of Au species to inactive Au nanoparticles of Au/CeO2&AC when placed in a C2H2/HCl stream can also rapidly rejuvenate. This is dramatically achieved by re-dispersing the Au particles to Au(0) atoms and oxidising to Au(I) entities, whereas Au/AC does not recover from the deactivation.

Neutral ketene is a crucial intermediate during zeolite carbonylation reactions. In this work, the roles of ketene and its derivates (viz., acylium ion and surface acetyl) associated with direct C−C bond coupling during the carbonylation reaction have been theoretically investigated under realistic reaction conditions and further validated by synchrotron radiation X-ray diffraction (SR-XRD) and Fourier transformed infrared (FT-IR) studies. It has been demonstrated that the zeolite confinement effect has significant influence on the formation, stability, and further transformation of ketene. Thus, the evolution and the role of reactive and inhibitive intermediates depend strongly on the framework structure and pore architecture of the zeolite catalysts. Inside side pockets of mordenite (MOR), rapid protonation of ketene occurs to form a metastable acylium ion exclusively, which is favorable toward methyl acetate (MA) and acetic acid (AcOH) formation. By contrast, in 12MR channels of MOR, a relatively longer lifetime was observed for ketene, which tends to accelerate deactivation of zeolite due to coke formation by the dimerization of ketene and further dissociation to diene and alkyne. Thus, we resolve, for the first time, a long-standing debate regarding the genuine role of ketene in zeolite catalysis. It is a paradigm to demonstrate the confinement effect on the formation, fate, and catalytic consequence of the active intermediates in zeolite catalysis.

TiO2-based powder materials have been widely studied as efficient photocatalysts for water splitting due to their low cost, photo-responsivity, earthly abundance, chemical and thermal stability, etc. In particular, the recent breakthrough of nitrogen-doped TiO2, which enhances the presence of structural defects and dopant impurities at elevated temperatures, exhibits an impressive visible-light absorption for photocatalytic activity. Although their electronic and optical properties have been extensively studied, the structure-activity relationship and photocatalytic mechanism remain ambiguous. Herein, we report an in-depth structural study of rutile, anatase and mixed phases (commercial P25) with and without nitrogen-doping by variable-temperature synchrotron X-ray powder diffraction. We report that an unusual anisotropic thermal expansion of the anatase phase can reveal the intimate relationship between sub-surface oxygen vacancies, nitrogen-doping level and photocatalytic activity. For highly doped anatase, a new cubic titanium oxynitride phase is also identified which provides important information on the fundamental shift in absorption wavelength, leading to excellent photocatalysis using visible light.