Combustion synthesis and photoluminescence of ZnS:Mn particles

An efficient process based on a solid-state combustion technique has been developed to produce high crystalline and micrometer sized particles of ZnS:Mn⁺² phosphor with sphalerite structure. The precursor mixture of 0.915Zn+S+0.05Mn+0.035ZnCl₂+kNaCl composition (where k is the mole number of NaCl) was combusted under the argon atmosphere followed by post-heat treatment procedure at 700 °C. It was shown that photoluminescence (PL) intensity of ZnS sample can be easily controlled through adjusting NaCl concentration. In the optimized reaction conditions ZnS samples have showed PL intensity almost comparable to that of a commercial one, despite the relatively low purity of precursor materials used. Many interesting phenomena such as high luminescent efficiency, pure cubic ZnS formation after the post-heat treatment and strong influence of Cl⁻ ion on PL intensity have been observed and discussed.     

Crystal and Molecular Structures of Tris(1-Methylimidazol-2-yl)Phosphine,Tris(4-Methylthiazol-2-yl)Phosphine and its Sulfide

Abstract  Two crystal structures of tris(azolyl)phosphines, PR₃ [R′ = 1-methylimidazol-2-yl (1) or R′′ = 4-methylthiazol-2-yl (2)], and the crystal structure of the sulfurisation product of 2, R′′₃PS (3), were determined. All compounds crystallise in polar space groups, 1 in the orthorhombic space group Pna2₁ with cell parameters a = 13.9779(15) ?, b = 9.2492(10) ? and c = 10.2439(11) ?; 2 in the trigonal space group, R3c, with a = 15.2383(10) ? and c = 10.5882(13) ? and 3 in the orthorhombic space group, Cmc2₁, with a = 13.466(3) ?, b = 9.308(2) ? and c = 12.207(3) ?. Graphical Abstract  This article presents two crystal structures of tris(azolyl)phosphines and one of a tris(thiazolyl)phosphine sulfide, a compound which show potential for wide application in coordination chemistry due to their multidentate nature.      

The reactions between [RuHCl(CO)(PPh3)3] and quinoline carboxylic acids

The reactions of [RuHCl(CO)(PPh₃)₃] with 8-hydroxy-2-methyl-quinoline-7-carboxylic acid and quinoline-2-carboxylic acid have been examined, and two novel ruthenium(II) complexes – [(PPh₃)₂RuH(CO)(C₁₀H₈NO₃)] and [(PPh₃)₂RuCl(CO)(C₉H₆O₂)] – have been obtained. The compounds have been studied by IR and UV–Vis spectroscopy, and X-ray crystallography. The molecular orbital diagrams of the complexes have been calculated with the density functional theory (DFT) method. The spin-allowed singlet–singlet electronic transitions of the compounds have been calculated with the time-dependent DFT method, and the UV–Vis spectra of the compounds have been discussed on this basis.     

Z-Scheme In2S3/NU-1000 Heterojunction for Boosting Photo-Oxidation of Sulfide into Sulfoxide under Ambient Conditions

Photocatalytic oxidation of sulfide into sulfoxide has attracted extensive attention as an environmentally friendly strategy for chemical transformations or toxic chemicals degradation. Herein, we construct a series of In₂S₃/NU-1000 heterojunction photocatalysts, which can efficiently catalyze the oxidation of sulfides to form sulfoxides as the sole product under LED lamp (full-spectrum) illumination in air at room temperature. Especially, the sulfur mustard simulant, 2-chloroethyl ethyl sulfide (CEES), can also be photocatalytically oxidized with In₂S₃/NU-1000 to afford nontoxic 2-chloroethyl ethyl sulfoxide (CEESO) selectively and effectively. In contrast, individual NU-1000 and In₂S₃ show very low catalytic activity on this reaction. The significantly improved photocatalytic activity is ascribed to the constructing of an efficient Z-scheme photocatalysts In₂S₃/NU-1000, which exhibits the enhancement of light harvesting, the promotion of photogenerated electron-hole separation, and the retention of high porosity of the parent MOF. Moreover, mechanism studies in photocatalytic oxidation reveal that the superoxide radical (^.O₂⁻) and singlet oxygen (¹O₂) are the main oxidative species in the oxidation system. This work exploits the opportunities for the construction of porous Z-scheme photocatalysts based on the photoactive MOFs materials and inorganic semiconductors for promoting catalytic organic transformations. More importantly, it provides a route to the rational design of efficient photocatalysts for the detoxification of mustard gas.     

ThioCORMates: Tunable and Cost-Effective Carbon Monoxide-Releasing Molecules

Carbon monoxide-releasing molecules (CORMs) can offer a safer alternative to CO delivery than the use of CO gas cylinders. Upon treatment with an amine base, S-aryl thioformates (“thioCORMates”) release CO nearly quantitatively at room temperature, a gas which can then be harnessed for carbonylative cross-coupling, biological study, or inorganic synthesis. These bench-stable molecules are easily synthesized from the corresponding thiophenol and can be electronically tuned to release CO at different rates-from less than 1 min to greater than 1 h-offering a practical alternative to existing CORM technology. Finally, isotopically labeled ¹³CO can be conveniently generated and used, with the thioCORMate synthesized from ¹³C-formic acid.     

Synthesis of size-tunable zinc blende ZnS nanocrystals

Quasi-polyhedral ZnS nanocrystals with monodisperse tunable sizes of 40, 52, 62, 73, 82, 94, 103, and 110 nm have been synthesized in aqueous solution by regulating the amounts of thioacetamide, zinc acetate, and acetic acid added. The mixture was heated to 120°C in an oven for 10–20 min to produce the nanocrystals. Structural characterization reveals the formation of cubic zinc blende ZnS with some polycrystallinity, which possibly influences their optical properties, that is, the measured band gaps do not give a continuous narrowing trend with increasing particle size. However, when particle sizes are expressed in terms of volumes, the absorption band positions show steady red shifts with increasing crystal dimensions and very small wavelength changes for nanocrystals beyond 90 nm. Thus, these ZnS nanocrystals still possess some size-dependent optical properties despite their polycrystalline nature.     

结晶／结晶共混体系PPS／PEEK中PPS组分的结晶熔融行为（Ⅱ）──熔融条件对退火样品的影响

结晶／结晶共混体系ＰＰＳ／ＰＥＥＫ中ＰＰＳ组分的结晶熔融行为（Ⅱ）──熔融条件对退火样品的影响麦堪成，许家瑞，梅震，曾汉民（广州中山大学材料科学研究所，广州，５１０２７５）关键词聚苯硫醚，聚醚醚酮，结晶熔融行为，熔融双峰聚苯硫醚（ＰＰＳ）的结晶熔融行...     

Efficient microwave syntheses of the compounds Os3(CO)11L, L = NCMe, py, PPh3

The results of simple microwave-assisted ligand substitution reactions of Os₃(CO)₁₂ are reported. In a remarkably short period of time, the labile complex Os₃(CO)₁₁(NCMe) is prepared in high yield without the need for a decarbonylation reagent such as trimethylamine oxide. Microwave irradiation of Os₃(CO)₁₂ in a relatively small amount of acetonitrile is shown to be a useful first step in two-step, one-pot syntheses of the cluster complexes Os₃(CO)₁₁(py) and Os₃(CO)₁₁(PPh₃).     

Effect of Diluent Mixture on Porous Structure of Polyphenylene Sulfide via Thermally Induced Phase Separation

Polyphenylene sulfide (PPS) microporous membranes were prepared via the thermally induced phase separation process using diluent mixtures of diphenyl ether (DPE) and diphenyl ketone (DPK). The effects of DPE ratio to DPK in the diluent mixture on the microstructure were investigated. The results showed that the pore morphology of the membranes prepared from the diluent mixture was different from those of fabricated from pure diluents. Moreover, the pore structures of the membranes were changed along with the variation of the diluent composition.