European Journal of Inorganic Chemistry最新文献

Thiolate-bridged diiron complexes have drawn extensive attention due to their wide applications in the biomimetic simulation for the structure and function of various metalloenzymes and the related bioinspired catalysis. Through the introduction of the functional subunit into the bridging thiolate ligands, the resulting thiolate-bridged diiron complexes with different geometric and electronic structures can exhibit distinct reactivity. Herein, we utilize a half-sandwich type of mononuclear iron complex as the reaction precursor to construct two novel thiolate-bridged diiron complexes featuring the benzimidazole moiety through the oxidative dimerization strategy. X-ray diffraction analysis reveals the two thiolate ligands containing the benzimidazole group in a syn arrangement bridge the two iron centers through the sulfur and nitrogen atoms. Furthermore, Mössbauer spectroscopy and computational studies suggest two complexes both possess two low-spin Fe^III ions, but adopt different magnetic couplings to give different electronic structures. Notably, difference in geometric and electronic structures between two complexes results in the distinct reactivity toward the azide species.

The unique physical and chemical properties of erythrosiderite-halides make them candidates for semiconductor materials and optoelectronic devices. However, research on the optoelectronic properties of these materials is still relatively limited. This study presents the crystal structure and optoelectronic properties of Cs₂FeCl₅⋅H₂O erythrosiderite halide. The results show that Cs₂FeCl₅⋅H₂O is an orange-red needle-like crystal, with its crystal system and space group belonging to the orthorhombic system and Cmcm(63), respectively. Photodetectors made from Cs₂FeCl₅⋅H₂O exhibit stable photocurrent responses in the visible light range (from 397 to 564 nm). Under conditions of a light intensity of 30 W/m² at 397 nm with a bias voltage of 4.5 V, the responsivity of Cs₂FeCl₅⋅H₂O is 8.41 mA/W, and the detectivity is 4.43 × 10⁶ Jones. There is a strong linear relationship between the net photocurrent density of Cs₂FeCl₅⋅H₂O and light intensity, as well as a strong linear relationship between responsivity and voltage, with R²=0.96. Thus, Cs₂FeCl₅⋅H₂O has excellent optoelectronic performance and is a promising compound for optoelectronic applications.

Metal oxo complexes are potentially useful for the catalytic oxidation of ammonia to produce nitrite/nitrate or for the construction of ammonia fuel cell. In the work we have studied the kinetics and mechanisms of the oxidation of ammonia by ferrate(VI) (FeO₄^2–), a well-defined metal oxo species. The kinetics was investigated over a pH range of 7.5 to 10, the rate-law is rate=k₂[ferrate][ammonia]. k₂ decrease with increasing pH, the results indicated that at pH 7.5 the reacting species are HFeO₄^– and NH₄⁺, while at pH >9 the reacting species are FeO₄^2– and NH₃. At pH 7.5 the reaction occurs according to the following stoichiometry: 8HFeO₄^– + 3NH₄⁺ + 3H₂O →8Fe(OH)₃ + 3NO₃^– + 2OH^–. Nitrate is also formed as the predominantly product at higher pHs. Based on the experimental results and DFT calculations, the proposed mechanism involves an oxygen-atom transfer from ferrate(VI) to ammonia to produce hydroxylamine, which is then rapidly oxidized by excess ferrate to nitrate.

The Front Cover shows a naphthyl island that supports the growth of two P-trees, with a family of tigers moving from tree to tree. The tigers move towards the P-tree full of purple fruit, representing the intense colour of the title compound, and its electron-rich phosphinidene centre. The vast network of roots growing from this tree into the naphthyl island indicates the electron delocalisation within this system, guarded by two rare amino-parrots. More information can be found in the Research Article by L. N. Kreimer and T. J. Hadlington. Cover produced by M. Neuwirt and L. N. Kreimer

The halogenation of diferrocenyltelluride, Fc₂Te, with XeF₂, PhICl₂ and I₂ afforded the diferrocenyltellurium dihalides Fc₂TeX₂ (X=F, Cl, I). Halide exchange of Fc₂TeCl₂ with KBr yielded Fc₂TeBr₂. The oxidation of Fc₂Te with NO[SbF₆] and K[B(C₆F₅)₄] provided the triferrocenyltelluronium salt [Fc₃Te][B(C₆F₅)₄] and the dinuclear nitrosyl iron complex Fe₂(μ-TeFc)₂(NO)₄. The new compounds were comprehensively characterized by multinuclear NMR spectroscopy (¹²⁵Te, ¹⁹F, ¹³C, ¹H), UV/vis absorption spectroscopy, cyclic voltammetry, LIFDI-TOF mass spectrometry and single crystal X-ray diffraction.

A catalyst for an electrocatalytic oxygen evolution reaction (OER) is a key component of the large-scale storage of renewable energy through the conversion of water into oxygen and hydrogen. Iron-based selenide materials are currently being considered as potential options for electrocatalytic oxygen evolution reaction (OER) because of their, widespread availability, low cost, and outstanding performance. In this study, we employed a thermal decomposition method to synthesize all stable phases of the Fe−Se system, including Fe₇Se₈, Fe₃Se₄, FeSe₂, and FeSe. Additionally, we slurry-coated these phases onto a three-dimensional (3D) nickel foam substrate. The prepared 3D electrodes of Fe₇Se₈, Fe₃Se₄, FeSe₂, and FeSe exhibit remarkably low overpotentials of 270, 276, 299, and 289 mV at a current density of 50 mA/cm² for OER. In addition, the catalytic activity for OER is also tested on glassy carbon electrodes to compare its performance with the Ni-foam 3D substrate. The Fe₇Se₈ phase in the Fe−Se system exhibits the highest catalytic activity towards OER on both substrates due to variations in the Fe²⁺/Fe³⁺ ratio and the presence of Fe vacancies (cation vacancies) within the crystal lattice. Moreover, a faradaic efficiency of 98 % was exhibited by Fe₇Se₈ for the oxygen evolution reaction (OER).

The reactions of the nitrides Mg₃N₂, Ca₃N₂, BN, Si₃N₄ and Mo₂N with anhydrous liquid HF (aHF) were investigated at 20 and 80 °C. While BN, Si₃N₄, and Mo₂N did not react under these conditions, Mg₃N₂ and Ca₃N₂ were converted to MgF₂ and CaF₂. In the reaction of Ca₃N₂ with MoF₆ in aHF, adventitious moisture that diffused through the walls of the reaction vessel led to the formation of the compound Ca[Mo₂O₂F₉]₂ ⋅ HF. We then discovered that it can also be made directly from the reaction of CaCl₂ with MoOF₄ in aHF. The compound was characterized by single crystal and powder X-ray diffraction and quantum-chemical calculations on the solid allowed for the assignment of the IR and Raman bands.

Palladium dichloride (6-10) and nickel dichloride (11-15) complexes of a series of N-substituted/functionalized bis(diphenylphosphino)amine-type ligands (1-5) were synthesized and characterized, using multinuclear NMR and FT-IR spectroscopic techniques, mass spectrometry and elemental analysis. The solid-state structures of two palladium(II) (6 and 8⋅2CHCl₃) and two nickel(II) (12 and 15) complexes could be confirmed by single-crystal X-ray diffraction studies. All the complexes were evaluated as catalysts in the Suzuki-Miyaura cross-coupling reaction. Applying what appeared, from the literature, as the optimized reaction conditions for such complexes, i. e. Cs₂CO₃ as base and 1,4-dioxane as solvent, the palladium catalysts were found very efficient for the coupling of phenylboronic acid and aryl bromides functionalized with weak and moderate electron donating groups (EDGs) and weak and moderate electron withdrawing groups (EWGs). In contrast, reduced activity was observed for aryl bromides functionalized with strong EDGs and EWGs and no activity for aryl chlorides. Under the same reaction conditions, the nickel catalysts were completely inactive. Applying different and “greener” reaction conditions, i. e. K₃PO₄ as base and tert-amyl alcohol as solvent, the nickel catalysts efficiently converted various aryl bromides and chlorides with a pool of aryl boronic acids, therefore clearly surpassing their palladium analogues at lower cost, economically and environmentally. Surprisingly, these reaction conditions could also be successfully applied to the palladium complexes, improving their performances (activity towards aryl chlorides) and offering a “greener” alternative to the common conditions.

Nine new ruthenium complexes featuring nitrogen and phosphorus donor ligands were synthesised from a Ru precursor featuring a rigid ONO-pincer ligand. The choice of nitrogen- and phosphorous-based ancillary ligands was guided by a careful evaluation of their different electronic and steric properties. This evaluation aimed to understand how these ligands, once coordinated, could influence the structural, electronic, and catalytic activity of the corresponding complexes. The range of complexes showed moderate catalytic activity in the transfer hydrogenation of alcohols, with the best performing catalyst achieving 96 % conversion in 1 hour (TON=96, TOF=96 h⁻¹). All complexes were characterised using ¹H, ¹³C, ³¹P (where applicable) NMR spectroscopy, CHN (microanalysis) and HR-MS analyses. Single crystal structures were obtained for all nine new complexes, as well two new polymorphs of the precursor complex. Complimentary electrochemical (cyclic voltammetry) and density functional theory (DFT) studies provided additional insights into the structural and electronic properties of the different complexes.

The Front Cover illustrates plutonium silicate crystals synthesized at Savannah River National Laboratory. The crystals were prepared by a flux growth method and represent a new crystal with Pu in its structure. These types of crystals are being investigated to better understand the immobilization of transuranic elements from nuclear waste. The Savannah River Site's F Area tank farm is in the background. More information can be found in the Research Article by H.-C. zur Loye and co-workers.