Occurrence of room temperature ferromagnetism is demonstrated in pulsed laser deposited thin films of Sn 1-x Co x O 2-δ (x<0.3). Interestingly, films of Sn 0.95 Co 0.05 O 2-δ grown on R-plane sapphire not only exhibit ferromagnetism with a Curie temperature close to 650 K, but also a giant magnetic moment of 7 ± 0.5 µ B /Co, not yet reported in any diluted magnetic semiconductor system. The films are semiconducting and optically highly transparent.

Copper oxide clusters synthesized via atomic layer deposition on the nodes of the metal-organic framework (MOF) NU-1000 are active for oxidation of methane to methanol under mild reaction conditions. Analysis of chemical reactivity, in situ X-ray absorption spectroscopy, and density functional theory calculations are used to determine structure/activity relations in the Cu-NU-1000 catalytic system. The Cu-loaded MOF contained Cu-oxo clusters of a few Cu atoms. The Cu was present under ambient conditions as a mixture of ∼15% Cu and ∼85% Cu. The oxidation of methane on Cu-NU-1000 was accompanied by the reduction of 9% of the Cu in the catalyst from Cu to Cu. The products, methanol, dimethyl ether, and CO, were desorbed with the passage of 10% water/He at 135 °C, giving a carbon selectivity for methane to methanol of 45-60%. Cu oxo clusters stabilized in NU-1000 provide an active, first generation MOF-based, selective methane oxidation catalyst.

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Farha and colleagues have developed a strategy for expanding the pore apertures of csq-net Zr-based MOFs to obtain an isoreticular series of MOF structures with pore apertures ranging from 3.3 to 6.7 nm. Enzymes immobilized in the MOF are accessible to coenzymes and show higher activity than that of the free enzymes.

Many microscopic investigations of materials may benefit from the recording of multiple successive images. This can include techniques common to several types of microscopy such as frame averaging to improve signal-to-noise ratios (SNR) or time series to study dynamic processes or more specific applications. In the scanning transmission electron microscope, this might include focal series for optical sectioning or aberration measurement, beam damage studies or camera-length series to study the effects of strain; whilst in the scanning tunnelling microscope, this might include biasvoltage series to probe local electronic structure. Whatever the application, such investigations must begin with the careful alignment of these data stacks, an operation that is not always trivial. In addition, the presence of low-frequency scanning distortions can introduce intra-image shifts to the data. Here, we describe an improved automated method of performing non-rigid registration customised for the challenges unique to scanned microscope data specifically addressing the issues of low-SNR data, images containing a large proportion of crystalline material and/or local features of interest such as dislocations or edges. Careful attention has been paid to artefact testing of the non-rigid registration method used, and the importance of this registration for the quantitative interpretation of feature intensities and positions is evaluated.

The atomic‐scale structure, composition, and chemistry of grain boundaries in two fluorite‐structured ceramic materials were characterized by a combination of Z‐contrast imaging and electron energy‐loss spectroscopy (EELS). In the case of a symmetric 24° [001] tilt bicrystal of yttria‐stabilized‐zirconia (YSZ), a shift in the zirconium M‐edge onset and a change in the yttrium and zirconium M‐edge ratios at the boundary indicate an increase in the number of electrons in the boundary plane. A detailed study of the structure and composition indicates that this is caused by an increase in the number of oxygen vacancies in the grain boundary core that is partially compensated by yttrium segregation. Studies of grain boundaries in an industrial Gd‐doped ceria ceramic reveals similar changes in vacancy/dopant profiles indicating that these effects may be generic to grain boundaries in fluorite‐structured materials.

A Keggin-type polyoxometalate (H3PW12O40) was incorporated into a mesoporous Zr-based MOF (NU-1000) via an impregnation method in aqueous media, resulting in the hybrid material, PW12@NU-1000. The POM@MOF composite was characterized by a suite of physical methods, indicating the retention of crystallinity and high porosity of the parent MOF. The hybrid material was also stable to leaching in aqueous media at varying pH. Finally, the material was tested as a heterogeneous catalyst for the oxidation of 2-chloroethyl ethyl sulfide using hydrogen peroxide as the oxidant. PW12@NU-1000 was shown to have a higher catalytic activity than either of the individual constituents alone.

Mononuclear and dinuclear copper species were synthesized at the nodes of an NU-1000 metal–organic framework (MOF) via cation exchange and subsequent oxidation at 200 °C in oxygen. Copper-exchanged MOFs are active for selectively converting methane to methanol at 150–200 °C. At 150 °C and 1 bar methane, approximately a third of the copper centers are involved in converting methane to methanol. Methanol productivity increased by 3–4-fold and selectivity increased from 70% to 90% by increasing the methane pressure from 1 to 40 bar. Density functional theory showed that reaction pathways on various copper sites are able to convert methane to methanol, the copper oxyl sites with much lower free energies of activation. Combining studies of the stoichiometric activity with characterization by in situ X-ray absorption spectroscopy and density functional theory, we conclude that dehydrated dinuclear copper oxyl sites formed after activation at 200 °C are responsible for the activity.