Five new quaternary isostructural rare-earth sulfides, Al0.57Gd3(Si0.27Al0.73)S7 (1), Al0.55Dy3(Si0.34Al0.66)S7 (2), Al0.50Y3(Si0.50Al0.50)S7 (3), Al0.44Gd3(Si0.70Al0.30)S7 (4) and In0.33Sm3SiS7 (5), have been synthesized by facile solid-state reactions. They crystallize in the 3-D ALn3EQ7 structure type in the hexagonal chiral space group P63. The structures feature a 3-D host framework constructed by Ln-S bicapped trigonal prisms, in which the octahedral and tetrahedral interspaces are occupied by A and E atoms, respectively. The investigation of optical and magnetic properties of 4 indicates that it is a semiconductor and behaves antiferromagnetic-like interaction.
GUO ShengPing, GUO GuoCong & HUANG JinShun State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China
The reaction of CdCl2 with 6,7-dicyanodipyridoquinoxaline （DICNQ） by solvothermal reaction gives rise to a coordination polymer [CdCl2（DICNQ）]n 1. Single-crystal X-ray diffraction analysis reveals that the compound in space group Pbcn creates 1-D chloro-bridging chains. Crystal data for 1： a = 6.756（1）, b = 35.371（6）, c = 7.027（1）A , V = 1679.1（5） A^3, Z = 4.00, C16H6CdCl2N6, Mr = 465.57, Dc = 1.842 g/cm^3, μ = 1.630 mm-1, F（000） = 904, S = 1.005 and T = 293（2） K. The final R = 0.0376 and wR = 0.1029 for 1291 observed reflections with I 〉 2σ（I）, and R = 0.0499 and wR = 0.1125 for all data. The 1-D chloro-bridging chains are parallel-stacked in the a and b directions, and further stabilized through π-stacking interactions, hydrogen-bonding interactions and C≡N···π interactions to generate a 3-D structure. Compound 1 displays intense bluish-green photoluminescence from the intraligand charge-transfer of the DICNQ ligand and the Cl--to-DICNQ charge-transfer mechanism which is probed by the density of states （DOS） calculations.
Two new quaternary sulfides,La3Sn0.25GeS71 and Sm3 Sn0.25GeS72,have been synthesized by a facile solid-state reaction,and their crystal structures were determined by singlecrystal X-ray diffraction analysis.The two compounds crystallize in the P6 3 space group,and the crystal data are as follows-La3Sn0.25GeS7：a=10.3335（7）,c=5.8455（7）,Z=2;Sm3Sn0.25GeS7：a=9.999（3）,c=5.787（2）,Z=2.Single-crystal analysis indicated that the two compounds consist of three types of building blocks：LnS 8 anti-tetragonal prism,SnS 6 octahedron,and GeS 4 tetrahedron.
Nanoscale tetragonal BiOCl samples have been synthesized using Bi[SC12H25]3 and CHCl3 as bismuth and chlorine sources by solvothermal reactions. The structure, morphology, and formation process have been investigated by SEM, TEM, HRTEM, XRD, and EDX analyses. The layered crystal structure feature of BiOCl may induce the growth of nano plates, which can subsequently aggregate into 3D spherical or flower-like microstructures under the presence of ethanol. The reaction temperature and the identity of secondary solvent influence the morphology. The yield of BiOCl depends on the completeness of the reaction and the degree of a competition reduction of BiOCl to Bi by ethanol. The as-synthesized 3D quasi-spherical BiOCl sample has an optical band gap of 3.15 eV, and shows much better photocatalytic performance on the degradation of methyl orange than that of commercial P25.
A series of Li4Ti5O12 materials were prepared by three different methods： solvothermal, sol-gel, and solid-state reaction methods. Phase composition, morphology, and particle sizes of the samples were studied by powder X-ray diffraction （XRD） and scanning electron microscopy （SEM）. Electrochemical properties of the samples were investigated by charge-discharge tests. It is demonstrated that both sol-gel and solid-state reaction methods provided good control over the chemical composition and microstructure of the active material, in which sol-gel method yielded a fine Li4Ti5O12 spinel having an initial specific capacity of 146 mAh g-1 and low capacity fade during cycling. Comparatively, the solid-state method is simple and promising to prepare Li4Ti5O12 for commercial applications.
Well defined BiOI nanolamellas and BiSI nanorods have been synthesized by a solventless method. The phase identity, morphology, growth orientation, and conversion from lamella to rod have been investigated. Several experimental facts suggest that the growth orientations of BiOI nanolamellas and BiSI nanorods are guided by their corresponding crystal structure motifs. The optical band gaps of BiOI and BiSI are measured to be 1.97 and 1.61 eV, and the visible light photocatalytic activity of BiOI lamellas is primarily measured.
A new quaternary sulfide, Al0.36Sm3Ge0.98S7 1, has been prepared by a facile solidstate reaction, and its crystal structure was determined by single-crystal X-ray diffraction analysis. It crystallizes in the hexagonal space group P63 with a = 9.964（1）, c = 5.768（2）A, V = 495.9（1）A^3 and Z = 2. In the crystal structure of 1, Al^3＋ and Ge^4＋ occupy the octahedral and tetrahedral interspaces of the 3-D main-framework constructed by SmS8 bicapped trigonal prisms, respectively. The investigation of optical and magnetic properties of 1 indicates that its optical band gap is 2.18 eV and it shows antiferromagnetic-like interaction.
A series of Bi2O3 were prepared by a facile hydrothermal method using NaOH and ammonia as the mineralizers. The products were characterized by XRD, IR, UV-vis diffuse reflectance spectra, and photodegradation of Rhodamine B dye. Simply using NaOH to supply a strong base condition, single phase α-Bi2O3 was formed. When changing the amount of NaOH and ammonia, mixed phases of α-Bi2O3, （BiO）4CO3（OH）2 and Bi2O2CO3 were obtained. All samples were found to show photocatalytic activities towards the degradation of Rhodamine B dye under UV light irradiation, in which mixed phase samples showed higher activities than single phase α-Bi2O3 possibly owing to the synergistic effect of the mixed phases.
