Surfactant-thermal method to prepare two novel two-dimensional Mn–Sb–S compounds for photocatalytic applications

Hydrazine-Assisted Synthesis, Structures, Photoelectricity, and Photocatalysis of Ternary Mercury-Tellurostannate Hybrids with Transition-Metal Complexes

Tellurostannates are traditionally prepared by multistep reactions using the tellurides SnTe, SnTe2, K4SnTe4, or A6SnTe6 (A = K, Rb, or Cs) as precursors, which are usually prepared by the molten reaction of alkali metals Sn and Te under harsh synthetic conditions. Differently, ternary Hg-tellurostannate hybrids [Mn(en)3]HgSnTe3(Te2) (1) (en = ethylenediamine), [Mn(dien)2]HgSnTe3(Te2) (2), and [Fe(dien)2]HgSnTe3(Te2) (3) (dien = diethylenetriamine) were synthesized by one-pot reactions using Sn and Te powders as starting materials in the presence of hydrazine under mild solvothermal conditions. In 1, HgTe3 and SnTe4 units are joined via Te-sharing to form a 1-D polymeric chain [HgSnTe3(Te2)]n2n-, while the [HgSnTe3(Te2)]n2n- chains in 2 and 3 are composed of HgTe4 and SnTe4 units. The common feature of the [HgSnTe3(Te2)2-]n chains in 1-3 is that they are constructed by both the telluride anion Te2- and the polytelluride anion Te22-. 1-3 exhibited strong photocurrent responses with current densities of 5.26, 3.38, and 3.94 μA cm-2, respectively. They showed effective photocatalytic activities for methylene blue degradation with degradation ratios in the range of 85.3-94.6% after light irradiation for 80 min. Investigation of the photocatalytic mechanism showed that •O2- radicals and h+ holes were the main active substances in the photodegradation.

Crystalline chalcogenidometalate-based compounds from uncommon reaction media

Chalcogenides are one of the most versatile inorganic materials families, further subdivided into a large variety of specific groups of compounds, ranging from neat binary or multinary solids and nanoparticles of the same formal compositions, both in crystalline or non-crystalline form, to complicated open-framework structures and cluster compounds, also including organ(ometall)ic derivates of the latter. The large variety regarding both the compositions and the structures is associated with an enormous variety of properties, ranging from simple or high-tech pigments through a multitude of opto-electronic devices and electrolytes to materials for ion separation or high-sophisticated catalysts. Naturally, this also goes hand in hand with a corrosponding breadth of synthesis strategies. Traditionally, chalcogenides have been accessed via high-temperature methods, which continuously have been replaced by lower-temperature approaches for economical and ecological reasons. Moreover, more recent methods also showed that new types of chalcogenide materials can be obtained under such milder conditions that are not accessible via traditional routes. To shed light onto one of the numerous families of chalcogenides, this feature article summarizes current achievements in the generation of multinary chalcogenidometallate-based clusters and networks via non-classical routes, using ionic liquids, surfactants, or hydrazine as reaction media at moderately elevated termperature.

A3Mn2Sb3S8 (A = K and Rb): a new type of multifunctional infrared nonlinear optical material based on unique three-dimensional open frameworks

A new type of multifunctional IR-NLO material, A₃Mn₂Sb₃S₈ (A = K and Rb), with unique 3D open frameworks has been developed using a facile surfactant–thermal method.

Synthesis and crystal structure of catena-poly[[bis[(2,2';6',2''-terpyridine)-manganese(II)]-μ4-penta-thio-dianti-monato] tetra-hydrate] showing a 1D MnSbS network

The asymmetric unit of the title compound, {[Mn2Sb2S5(C15H11N3)2]·4H2O} n , consists of two crystallographically independent MnII ions, two unique terpyridine ligands, one [Sb2S5]4- anion and four solvent water mol-ecules, all of which are located in general positions. The [Sb2S5]4- anion consists of two SbS3 units that share common corners. Each of the MnII ions is fivefold coordinated by two symmetry-related S atoms of [Sb2S5]4- anions and three N atoms of a terpyridine ligand within an irregular coordination. Each two anions are linked by two [Mn(terpyridine)]2+ cations into chains along the c-axis direction that consist of eight-membered Mn2Sb2S4 rings. These chains are further connected into a three-dimensional network by inter-molecular O-H⋯O and O-H⋯S hydrogen bonds. The crystal investigated was twinned and therefore, a twin refinement using data in HKLF-5 [Sheldrick (2015 ▸). Acta Cryst. C71, 3-8] format was performed.

Hydrazine-solvothermal methods to synthesize polymeric thioarsenates from one-dimensional chains to a three-dimensional framework

A series of polymeric Mn(ii)-thioarsenates [Mn(en)₃]_n[(N₂H₄)₂Mn₆(μ₆-S)(μ-N₂H₄)₂(μ₃-AsS₃)₄]_n (1), [N₂H₅]_n[{Mn(μ-N₂H₄)₂(μ-AsS₄)}·0.5en]_n (2), [Mn(μ-trien){Mn(μ-N₂H₄)(μ-AsS₃)}₂]_n (3), [{Mn(N₂H₄)}₂(μ-N₂H₄)₂{Mn(μ-N₂H₄)₂(μ-AsS₃)₂}]_n (4), [Mn₃(μ-N₂H₄)₆(μ₃-AsS₄)(μ₂-AsS₄)]_n (5), and [Mn(NH₃)₆]_n[{Mn(NH₃)(μ-AsS₄)}₂]_n (6) were synthesized using a hydrazine-solvothermal method. The thioarsenate units AsS₃ and AsS₄ coordinate to Mn(ii) ions with variable coordination modes, forming a Mn–As–S ternary cluster (1), chains (2, 4–6), and layers (3), respectively. The hydrazine molecules act as inter-cluster, intra-chain and intra-layer bridging ligands to join the Mn(ii) ions, resulting in hydrazine hybrid 1-D, 2-D, and 3-D Mn(ii)-thioarsenate moieties in 1–5. Compounds 1–6 exhibit tunable semiconducting band gaps varying in the range of 2.19–2.47 eV. Compound 1 displays stronger antiferromagnetic coupling interactions than that of compound 2.

Mn(ii)-thioarsenates [Mn(en)₃]_n[Mn₆S(N₂H₄)₄(AsS₃)₄]_n (1), [N₂H₅]_n[{Mn(N₂H₄)₂(AsS₄)}·0.5en]_n (2), [Mn(trien){Mn(N₂H₄)(AsS₃)}₂]_n (3), [Mn₃(N₂H₄)₆(AsS₃)₂]_n (4), [Mn₃(N₂H₄)₆(AsS₄)₂]_n (5), and [Mn(NH₃)₆]_n[{Mn(NH₃)(AsS₄)}₂]_n (6) were prepared in N₂H₄ by solvothermal methods.

Syntheses, crystal structures, and photocatalytic properties of two ammonium-directed Ag–Sb–S complexes

Two novel crystalline Ag–Sb–S complexes show better photodegradation performance on CV than RhB.

Facile Hydrazine-Hydrothermal Syntheses and Characterizations of Two Quaternary Thioarsenates(III): Two-Dimensional SrAg4 As2 S6 ⋅2 H2 O and One-Dimensional BaAgAsS3

Two new quaternary thioarsenates(III), SrAg4 As2 S6 ⋅2 H2 O (1) and BaAgAsS3 (2), have been prepared through a hydrazine-hydrothermal method at low temperature. Compound 1 possesses a two-dimensional (2D) layer network, while compound 2 features a one-dimensional (1D) column structure. The detailed structure analysis indicates that Sr(2+) and Ba(2+) cations have different directing effects on the structures of thioarsenates(III). Both experimental and theoretical studies demonstrate that compounds 1 and 2 are narrow-gap semiconductors. Our success in synthesizing these two quaternary thioarsenates(III) proves that the hydrazine-hydrothermal technique is a powerful yet facile synthetic method for exploring new complex chalcogenides with diverse crystal structures and interesting physical properties.

A surfactant-thermal method to prepare crystalline thioantimonate for high-performance lithium-ion batteries

A novel crystalline thioantimonate prepared by a surfactant-thermal strategy demonstrates high performance as an anode material for Li-ion batteries.