铽、铕-邻啡啰啉-芳香化合物三元配合物的合成和性质研究

本文对Ln(phen)(C₆H₅COO)₃、Ln(phen)₂P-(OC₆H₄CHO)₃·3H₂O.Ln(phen)₂P-(OC₆H₄COOC₂H₅)₃(Ln=Tb、Eu)固体配合物的制备和光谱性质进行了研究。根据元素分析、红外光谱、摩尔电导测定,X射线粉末衍射、热重差热分析以及紫外可见光谱确定了其组成及配位形式,并对其发光性能进行了研究。     

Synthesis,crystal structure,and properties of a new cadmium(ΙΙ) polymer with mixed Cl−/SCN− ligands: [CdCl(SCN)] n

A 1-D chain complex, cadmium(ΙΙ) chloride thiocyanate (1), [CdCl(SCN)] _n was synthesized by evaporation and characterized by single-crystal X-ray diffraction and FT-IR techniques. The compound crystallizes in the space group Pnma of orthorhombic system with cell parameter a = 9.5967(7), b = 4.2595(3), and c = 10.1789(7) Å; V = 416.08(5) ų and Z = 4. The cadmium(ΙΙ) is five-coordinate, surrounded by one pair of (µ-1,1-NCS) bridging NCS^? and three Cl^? as a µ₃-linker coordinating three Cd(ΙΙ) centers, approximately a severely distorted square-pyramidal configuration. Cd(ΙΙ), Cl^?, and SCN^? form an infinite 1-D chain with chair-like features, a new example of mixed Cd–NCS–Cl discrete compounds. The photophysical properties of the crystals have been investigated with one emission peak at 473 nm observed for the title complex in the solid state, which exhibits blue luminescence. The mechanical properties of the crystals have been studied using Vickers microhardness tester and the hardness was 78.6 kg mm^?2.     

Synthesis,characterization and structure of oxorhenium(V) complexes with 2-methylmercaptobenzamide

The neutral, mononuclear complex [ReO(mta)₂Cl] (1) [Hmta?=?2-(methylmercapto)aniline] was prepared by reaction of trans-[ReOCl₃(PPh₃)₂] with a twofold molar excess of Hmta in methanol. The oxo-bridged dimer (μ-O)[ReO(mta)₂]₂ (2) was synthesized by reacting [ReOCl₃(PPh₃)₂] with a twofold excess of Hmta in a 9?:?1 acetone/water mixture. The compounds were characterized by spectroscopy and complex 1 also by X-ray crystallography. Complex 1 has a distorted octahedral geometry with the chloride coordinated trans to the oxo group, and with the chelating ligands in the equatorial plane in a cis-N cis-S configuration.     

Synthesis,structure, and magnetism of a ytterbium coordination polymer with 5-sulfonyl-1,2,4-benzenetricarboxylate and oxalate

[Yb₂(SBTC)(ox)(H₂O)₅] _n (1) (H₄-SBTC?=?5-sulfonyl-1,2,4-benzenetricarboxylic acid and ox?=?oxalate) has been hydrothermally synthesized by reaction of 5-sulfonyl-1,2,4-benzenetricarboxylic acid with Yb(NO₃)₃?5H₂O. In situ formation of oxalate derived from H₄-SBTC is unprecedented and adds a new oxalate formation reaction to in situ ligand syntheses. Compound 1 features a 2-D bilayered coordination network, which is further extended into a 3-D supramolecular framework through interlayered hydrogen bonds. Magnetic measurements on 1 indicate that there is an antiferromagnetic interaction between Yb(III) ions.     

Surface Organometallic Chemistry for Single-site Catalysis and Single-atom Catalysis

Although driven by different research interests, single-site catalysts and single-atom catalysts are both believed to be model systems bridging homogeneous and heterogeneous catalysis. The two concepts are similar but different. In this review, we will first explain the difference between single-atom catalysis and single-site catalysis, in terms of their goals, synthetic methods and coordination structures of corresponding catalysts. Then, we will introduce the surface organometallic chemistry method, a method traditionally used for synthesizing single-site catalyst. We will explain why it might benefit the single-atom catalysis community. At last, the choice of support to accommodate the method for synthesizing single-atom catalysts will be discussed.     

Single-atom Fe Embedded Co3S4 for Efficient Electrocatalytic Oxygen Evolution Reaction

Constructing atomically dispersed active sites with densely exposed and dispersed double metal-S_x catalytic sites for favorable OER catalytic activity remains rare and challenging. Herein, we design and construct a Fe₁S_x@Co₃S₄ electrocatalyst with Fe single atoms epitaxially confined in Co₃S₄ nanosheets for catalyzing the sluggish alkaline oxygen evolution reaction(OER). Consequently, in ultralow concentration alkaline solutions(0.1 mol/L KOH), such a catalyst is highly active and robust for OER with low overpotentials of 300 and 333 mV at current densities of 10 and 30 mA/cm², respectively, accompanying long-term stability without significant degradation even for 350 h. In addition, Fe₁S_x@Co₃S₄ shows a turnover frequency(TOF) value of 0.18 s⁻¹, nearly three times that of Co₃S₄(0.07 s⁻¹), suggesting the higher atomic utilization of Fe single atoms. Mössbauer and in-situ Raman spectra confirm that the OER activity of Fe₁S_x@Co₃S₄ origins from a thin catalytic layer of Co(Fe)OOH that interacts with trace-level Fe species in the electrolyte, creating dynamically stable active sites. Combined with experimental characterizations, it suggests that the most active S-coordinated dual-metal site configurations are 2S-bridged (Fe-Co)S₄, in which Co-S and Fe-S moieties are shared with two S atoms, which can strongly regulate the adsorption energy of reaction intermediates, accelerating the OER reaction kinetics.     

异原子配位结构碳基单原子电催化剂结构与性能相关性的研究进展

单原子催化剂是一类以相互孤立的单个金属原子作为催化活性中心的、 具有高原子经济性及高活性的负载型催化剂, 被广泛应用于能源电催化领域. 近年来, 通过使用两种或两种以上原子与活性中心金属原子配位, 构建具有异原子配位结构的单原子材料, 展现了优异的电催化性能. 研究发现, 这种不对称的配位结构有效调控了中心金属原子的电子结构, 优化了催化反应的吸附和脱附能量, 提高了电催化的性能. 本文综合评述了具有异原子配位结构碳基单原子电催化剂的合成策略、 表征技术与方法, 以及在前沿能源电催化应用中的催化剂性能与结构之间的构效关系, 并展望了异原子配位结构碳基单原子电催化剂的研究前景.