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The wide interest in developing green energy technologies stimulates the scientific community to seek, for devices, new substitute material platforms with low environmental impact, ease of production and processing and long-term stability. The synthesis of metal oxide (MO) semiconductors fulfils these requirements and efforts are addressed at optimizing their functional properties, through improvement of charge mobility or energy level alignment. Two MOs have rising perspectives for application in light harvesting devices, mainly for the role of charge selective layers but also as light absorbers, namely MoO3 (an electron blocking layer) and Co3O4 (a small band gap semiconductor). The need to achieve better charge transport has prompted us to attempt doping strategies with vanadium (V) ions that, when combined with oxygen in V2O5, produce a high work function MO. We report on subcritical hydrothermal synthesis of V-doped mesostructures of MoO3 and of Co3O4, in which a tight control of the doping is exerted by tuning the relative amounts of reactants. We accomplished a full analytical characterization of these V-doped MOs that unambiguously demonstrates incorporation of the vanadium ions in the MO crystal lattice, as well as effects on the optical properties and work function. We foresee a promising future use of these materials as charge selective materials in energy devices based on multilayer structures.

Genetically modified vaccinia viruses (VACVs) have been shown to possess profound oncolytic capabilities. However, tumor cell resistance to VACVs may endanger broad clinical success. Using cell mass assays, viral replication studies, and fluorescence microscopy, we investigated primary resistance phenomena of cell lines of the NCI-60 tumor cell panel to GLV-1h94, a derivative of the Lister strain of VACV, which encodes the enzyme super cytosine deaminase (SCD) that converts the prodrug 5-fluorocytosine (5-FC) into the chemotherapeutic compound 5-fluorouracil (5-FU). After treatment with GLV-1h94 alone, only half of the cell lines were defined as highly susceptible to GLV-1h94-induced oncolysis. When adding 5-FC, 85% of the cell lines became highly susceptible to combinatorial treatment, none of the tested tumor cell lines exhibited a &ldquo, high-grade resistance&rdquo, pattern. Detailed investigation of the SCD prodrug system suggested that the cytotoxic effect of converted 5-FU is directed either against the cells or against the virus particles, depending on the balance between cell line-specific susceptibility to GLV-1h94-induced oncolysis and 5-FU sensitivity. The data provided by this work underline that cellular resistance against VACV-based virotherapy can be overcome by virus-encoded prodrug systems. Phase I/II clinical trials are recommended to further elucidate the enormous potential of this combination therapy.

The temporary storage of oxygen in a solid catalyst is imperative for many important industrial oxidation reactions in the gas phase, for instance the post-treatment of automotive exhaust gas. CeO2 is a promising catalyst for the HCl oxidation (Deacon process) in order to recover Cl2. Employing shape- controlled CeO2 nanoparticles (cubes, octahedrons, rods) with facets of preferential orientations ((100), (111), (110)), we studied the activity and stability under two reaction conditions (harsh: Ar:HCl:O2 = 6:2:2 and mild: Ar:HCl:O2 = 7:1:2). It turns out that both activity and stability are structure sensitive. In terms of space time yield (STY), the rods are the most active particles, followed by the cubes and finally the octahedrons. Ceria also possesses high OSC (oxygen storage capacity) which is a measure of the oxygen quantity that material can store and release. This makes ceria suitable for redox reactions which usually follow Mars-van Krevelen mechanism (surface oxygen atoms directly involved in reactions). A peculiar mixed Ce-Zr (1:1) oxide, the ordered κ-phase, is a promising catalytic material exhibiting an extraordinarily high oxygen storage capacity (OSC) and high thermal and chemical stability. We elucidate the temperature-dependent transformation between the pyrochlore pyr-Ce2Zr2O7.3 and κCe2Zr2O8 phase upon oxygen uptake by in-situ X-ray diffraction, X-ray absorption and in-situ Raman spectroscopy, providing insights into the electronic and structural changes on the atomic level, which are at the heart of the extraordinarily high OSC. We demonstrate that the Ce3+ concentration can be followed during transformation in-situ by Raman spectroscopy of the electronic spin flip in the f-shell of Ce3+. The catalytic activity of the κ-Ce2Zr2O8 phase has been investigated without an additional active component such as Pt: While the high OSC of the kappa phase is beneficial for the oxidation of CO, the oxidation of HCl turns out to be not affected by the high OSC.

The temporary storage of oxygen in a solid catalyst is imperative for many important industrial oxidation reactions in the gas phase, for instance the post-treatment of automotive exhaust gas. A peculiar mixed Ce–Zr (1:1) oxide, the ordered κ-Ce2Zr2O8 phase, is a promising catalytic material exhibiting an extraordinarily high oxygen storage capacity (OSC) and high thermal and chemical stability. We elucidate the temperature-dependent transformation between the pyrochlore pyr- Ce2Zr2O7 and κ-Ce2Zr2O8 phase upon oxygen uptake by in situ X-ray diffraction, X-ray absorption, and in situ Raman spectroscopy, providing insights into the electronic and structural changes on the atomic level, which are at the heart of the extraordinarily high OSC. We demonstrate that the Ce3+ concentration can be followed during transformation in situ by Raman spectroscopy of the electronic spin flip in the f-shell of Ce3+. The catalytic activity of the κ-Ce2Zr2O8 phase was investigated without an additional active component such as noble metals (Pt, etc.). While the high OSC of the κ-phase is beneficial for the oxidation of CO, the oxidation of HCl turns out to be unaffected by the high OSC.

This document resumes the activity of the Italian CRG beamline at ESRF (LISA project) during year 2017. The features of the newly installed instrumentation are presented as well as statistic data on the beamline, hi-ghlight experiments and publications.

Temporary storage of oxygen in a solid catalyst is imperative for many important industrial oxidation reactions in the gas phase, for instance the post-treatment of automotive exhaust gas. A peculiar mixed Ce–Zr (1:1) oxide, the ordered κ-Ce2Zr2O8 phase, is a promising catalytic material exhibiting an extraordinarily high oxygen storage capacity (OSC) and high thermal and chemical stability. We elucidate the temperature-dependent transformation between the pyrochlore pyr- Ce2Zr2O7 and κ-Ce2Zr2O8 phase upon oxygen uptake by in situ X-ray diffraction, X-ray absorption, and in situ Raman spectroscopy, providing insights into the electronic and structural changes on the atomic level, which are at the heart of the extraordinarily high OSC. We demonstrate that the Ce3+ concentration can be followed during transformation in situ by Raman spectroscopy of the electronic spin flip in the f-shell of Ce3+. The catalytic activity of the κ-Ce2Zr2O8 phase was investigated without an additional active component such as noble metals (Pt, etc.). While the high OSC of the κ-phase is beneficial for the oxidation of CO, the oxidation of HCl turns out to be unaffected by the high OSC.

The temporary storage of oxygen in a solid catalyst is imperative for many important industrial oxidation reactions in the gas phase, for instance the post-treatment of automotive exhaust gas. A peculiar mixed Ce-Zr (1:1) oxide, the ordered -Ce2Zr2O8 phase, is a promising catalytic material exhibiting an extraordinarily high oxygen storage capacity (OSC) and high thermal and chemical stability. We elucidated the temperature-dependent transformation between the pyrochlore pyr- Ce2Zr2O7.3 and -Ce2Zr2O8 phase upon oxygen uptake by in-situ X-ray diffraction, X-ray absorption and in-situ Raman spectroscopy, providing insights into the electronic and structural changes on the atomic level, which are at the heart of the extraordinarily high OSC. We demonstrate that the Ce3+ concentration can be followed during transformation in-situ by Raman spectroscopy of the electronic spin flip in the f-shell of Ce3+. The catalytic activity of the k-Ce2Zr2O8 phase has been investigated without an additional active component such as Pt: While the high OSC of the kappa phase is beneficial for the oxidation of CO, the oxidation of HCl turns out to be not affected by the high OSC.