Ultrahard magnetism from mixed-valence dilanthanide complexes with metal-metal bonding

Magnetic effects of lanthanide bonding Lanthanide coordination compounds have attracted attention for their persistent magnetic properties near liquid nitrogen temperature, well above alternative molecular magnets. Gould et al . report that introducing metal-metal bonding can enhance coercivity. Reduction of iodide-bridged terbium or dysprosium dimers resulted in a single electron bond between the metals, which enforced alignment of the other valence electrons. The resultant coercive fields exceeded 14 tesla below 50 and 60 kelvin for the terbium and dysprosium compounds, respectively. —JSY

High specific surface CeO2-NPs doped loose porous C3N4 for enhanced photocatalytic oxidation ability

Porous C3N4 (PCN) is favored by researchers because it has more surface active sites, higher specific surface area and stronger light absorption ability than traditional g-C3N4. In this study, cerium dioxide nanoparticles (CeO2-NPs) with mixed valence state of Ce3+ and Ce4+ were doped into the PCN framework by a two-step method. The results indicate that CeO2-NPs are highly dispersed in the PCN framework, which leads to a narrower band gap, a wider range of the light response and an improved the separation efficiency of photogenerated charge in PCN. Moreover, the specific surface area (145.69 m2•g-1) of CeO2-NPs doped PCN is a 25.5 % enhancement than that of PCN (116.13 m2•g-1). In the experiment of photocatalytic selective oxidation of benzyl alcohol, CeO2-NPs doped porous C3N4 exhibits excellent photocatalytic activity, especially Ce-PCN-30. The conversion rate of benzyl alcohol reaches 74.9 % using Ce-PCN-30 as photocatalyst by 8 hours of illumination, which is 25.7 % higher than that of pure porous C3N4. Additionally, CeO2-NPs doped porous C3N4 also exhibits better photocatalytic efficiency for other aromatic alcohols.

John Goodenough and the Many Lives of Transition-Metal Oxides

In honor of John Goodenough's centennial birthday, I discuss some of his insights into magnetism and the role of mixed valence in transition-metal oxides. His ideas form an important part of the continuing evolution of our understanding of these fascinating materials with a wide range of technologically-important functionalities. In particular, will mention connections to phenomena such as colossal magnetoresistance, enhanced thermopower, and high-temperature superconductivity.

Synthesis and characterization of a uranium oxide hydrate framework with Sr(II) ions: Structural insights and mixed uranium valences

A mixed-valence uranium oxide hydrate framework with Sr2+ ions (UOF-Sr2) was synthesized hydrothermally and characterized with multiple structural and spectroscopic techniques. Compound UOF-Sr2 crystallizes in monoclinic space group C2/c, having...