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Two‐electron oxidative addition is one of the most important elementary reactions for d‐block transition metals but it is uncommon for f‐block elements. Here, we report the first examples of intermolecular oxidative addition of E−H (E=C, N) bonds to uranium(II) centers. The transient U(II) species was formed in‐situ by reducing a heterometallic cluster featuring U(IV)‐Pd(0) bonds with potassium‐graphite (KC8). Oxidative addition of C−H or N−H bonds to the U(II) centers was observed when this transient U(II) species was treated with benzene, carbazole or 1‐adamantylamine, respectively. The U(II) centers could also react with tetracene, biphenylene or N2O, leading to the formation of arene reduced U(IV) products and uranyl(VI) species via two‐ or four‐electron processes. This study demonstrates that the intermolecular two‐electron oxidative addition reactions are viable for actinide elements. [ABSTRACT FROM AUTHOR]

Keywords: luminescence; radiation detection; scintillators; uranium As a new area in this field, uranyl-bearing scintillators show intrinsic merits for designing new materials with X-ray detection capability, that is, a large photoelectric cross-section, high X-ray attenuation efficiency, and high crystal density. Luminescence, radiation detection, scintillators, uranium. [Extracted from the article]

X‐ray detectors with high sensitivity are of great significance in both civil and military fields. Over the past decades, great efforts have been made to improve the sensitivity in conventional inorganic materials, but mainly at the cost of increasing the energy consumption with a quite high operating voltage. Developing photosensitive ferroelectrics directly as detector materials may be a conceptually new strategy in view of the strong ferroelectric spontaneous polarization (Ps) that assists photoinduced carriers separation and transport. A high‐performance X‐ray detector in 2D hybrid halide perovskite ferroelectric (C4H9NH3)2(C2H5NH3)2Pb3Br10 (BA2EA2Pb3Br10) (Ps = 5 µC cm−2) is fabricated and exhibits an ultrahigh X‐ray sensitivity up to 6.8 × 103 µC Gyair−1 cm−2 even at a relatively low operating voltage, which is over 300‐fold larger than that of state‐of‐the‐art α‐Se X‐ray detectors. Such a brilliant figure‐of‐merit is largely attributed to the superior mobility–lifetime products associated with the strong ferroelectric polarization of BA2EA2Pb3Br10. As pioneering work, these findings inform the exploration of hybrid halide perovskite ferroelectrics toward high‐performance photoelectronic devices. [ABSTRACT FROM AUTHOR]

Various types of polyoxometalates (POMs) have been synthesized since the 19th century, but their assortment has been mostly limited to Groups 5 and 6 metals. Herein, a new family of POMs composed of a carbon group element as the addenda atoms with two distinct phases, LnPbOClO4‐1 (Ln = Sm to Ho, Y) and LnPbOClO4‐2 (Ln = Er and Tm) is reported. Both structures are built from [Ln6O8] rare‐earth metal hexamers being incorporated in [Pb18O32]/[Pb12O24] polyplumbites, and unbound perchlorates as charge‐balancing anions. Impressively, YPbOClO4‐1 and ErPbOClO4‐2 exhibit exceptional uptake capacities (434.7 and 427.7 mg g−1) toward ReO4−, a chemical surrogate for the key radioactive fission product in the nuclear fuel cycle 99TcO4−, which are the highest values among all inorganic anion‐exchange materials reported until now. The sorption mechanism is clearly elucidated and visualized by single‐crystal‐to‐single‐crystal structural transformation from ErPbOClO4‐2 to a perrhenate‐containing complex ErPbOReO4, revealing a unique ReO4− uptake selectivity driven by specific interaction within Pb···O‐ReO3− bonds. [ABSTRACT FROM AUTHOR]

The cover page for the February 2018 issue, Vol. 4 and issue No. 2 of the journal "Advanced Electronic Materials" is presented.

The crystal structures of compounds (III), (IV), (VI) and (VII) are determined by single crystal XRD. [ABSTRACT FROM AUTHOR]

Reactions of LnCl3 (Ln: La-Nd, Sm, Eu) with 11 M HClO4 in molten H3BO3 (autoclave, 240 °C, 3, 5, or 7 d) lead to the formation of Ln[B8O10(OH)6(H2O) (ClO4)]·0.5H2O (Ln: La-Nd, Sm), Pr[B8O11(OH)4(H2O) (ClO4)], Ln[B7O11(OH)(H2O)2 (ClO4)] (Ln: Pr, Nd, Sm, Eu), and Ce[B8O11(OH)4(H2O) (ClO4)] depending on the lanthanide metal and the reaction time. [ABSTRACT FROM AUTHOR]

Rb2 [(UO2)2B8O12F6] ·H2B4O7 is synthesized from mixtures of UO2(NO3)2, H3BO3, RbBF4, and H2O (autoclave, 220 °C, 5 d). [ABSTRACT FROM AUTHOR]

As revealed by single crystal XRD compounds (III) and (VII) crystallize in the space group P21/n with Z = 4. [ABSTRACT FROM AUTHOR]

(UO2)2 [UO4(trz)2](OH)2 (trz: 1,2,4-triazole) is obtained under mild solvothermal conditions by reaction of uranyl acetate and 1,2,4-triazole in a mixed solution of EtOH, MeCN, and H2O (autoclave, 150 °C, 4 d, 42% yield). [ABSTRACT FROM AUTHOR]

Colorless crystals of Na[(NpO2)4B15O24 (OH)5(H2O)](ClO4)·0.75H2O are prepared by reaction of NpO2(ClO4)2 and NaClO4 in a boric acid flux (autoclave, 220 °C, 3 d). [ABSTRACT FROM AUTHOR]

Ba5 [(UO2)(PO4)3(B5O9)] (H2O)0.125 is synthesized by solid state reaction of H3BO3, BPO4, UO2(NO3)2·6H2O, and BaCO3 (Pt crucible, 1000 °C, slow cooling to room temperature, 8-10% yield). [ABSTRACT FROM AUTHOR]

It is shown that UVO2+ ions can reside at UVIO22+ lattice sites during mild reduction and crystallization process under solvothermal conditions, yielding a complicated and rare mixed-valent uranium phosphonate compound that simultaneously contains UIV, UV, and UVI. The presence of uranium with three oxidation states was confirmed by various characterization techniques, including X-ray crystallography, X-ray photoelectron, electron paramagnetic resonance, FTIR, UV/Vis-NIR absorption, and synchrotron radiation X-ray absorption spectroscopy, and magnetism measurements. [ABSTRACT FROM AUTHOR]