球形Bi4Ti3O12制备及其可见光催化性能

采用水热法合成球形钛酸铋复合氧化物光催化剂,利用SEM、XRD和UV-Vis DRS等表征手段对复合氧化物的晶体结构、微观形貌和光学性能进行了分析,结果表明,制备的钛酸铋复合氧化物为10 nm的球形颗粒,具有良好的晶型结构,禁带宽度为2.7 nm,有较好的可见光吸收能力。以亚甲基蓝、甲基橙及酸性品红为目标污染物,研究了复合氧化物在可见光下的光催化降解有机污染物的性能,并对光催化降解机理进行了探讨。结果表明,在可见光照射下,该复合氧化物对酸性品红降解效果明显优于亚甲基蓝和甲基橙,光照150 min下,降解率可达91%。     

全固态Z-型CdS/Au/Bi2MoO6异质结的构筑及其光催化性能

采用简单的化学还原沉积和二次水热的方法成功制备了CdS和Au共同修饰Z型CdS/Au/Bi2MoO6(CdS/Au/BMO)光催化剂。通过X射线粉末衍射(XRD)、X射线光电子能谱(XPS)、透射电子显微镜(TEM)、扫描电子显微镜(SEM)等测试技术对其组成、形貌、光吸收特性和光电化学性能等进行系统表征。实验结果表明,CdS/Au/BMO-2复合材料在可见光照射下表现出最佳的降解效率,其降解RhB的速率常数约为BMO的8.8倍和CdS的20倍。Au NPs作为固态电子媒介,为光生电子的传输和转移提供了一个通道,同时Au NPs的表面等离子体共振(SPR)效应和CdS纳米粒子显著拓宽了催化体系对可见光的响应范围;通过对催化剂的组成、结构和光电性能表征,确定了CdS/Au/BMO的能带结构,进而探讨了CdS/Au/BMO活性增强机制。     

Synthesis and Characterization of a New 2D Ca(Ⅱ) Coordination Polymer Containing 1D Calcium-oxygen Chains

A new 2D Ca(Ⅱ) coordination polymer, [Ca(H2btc)(H2O)2]n(1, H4 btc = biphenyl-3,3',5,5'-tetracarboxylic acid), has been synthesized using the hydrothermal method and characterized by single-crystal X-ray diffraction, elemental analysis, IR, thermogravimetric analysis, and photoluminescent analysis. Complex 1 crystallizes in the monoclinic system, space group C2/c with a = 17.5676(15), b = 11.4496(8), c = 7.6197(8)A, β = 102.787(2)o, V = 1494.6(2) A3, Z = 4, D3 c = 1.797 Mg·m-, μ = 0.483 mm-1, F(000) = 832, the final R = 0.0348 and wR = 0.0915 for 1521 observed reflections with I 2σ(I). Complex 1 has a 2D network containing 1D calcium-oxygen chains. These 2D networks are further connected by O–H···O hydrogen bonding interactions to generate a 3D supramolecular structure.     

基于三联苯-2,2′,4,4′-四羧酸的二维双层锌(Ⅱ)配位聚合物的水热合成、晶体结构及荧光性质(英文)

采用水热法合成了一个配合物[Zn2(tpta)0.5(H2tpta)(dpe)(H2O)2]n(1)(H4tpta=三联苯-2,2′,4,4′-四羧酸,dpe=1,2-二(4-吡啶基)乙烯),并用元素分析、红外光谱、X-射线单晶衍射、热重分析和荧光分析对其进行了表征。晶体结构分析表明:该配合物属于三斜晶系,空间群为P1,a=1.017 4(2)nm,b=1.034 1(2)nm,c=1.883 1(4)nm,α=96.147(4)°,β=96.866(4)°,γ=98.023(4)°,V=1.932 2(7)nm3,Z=2,Dc=1.640 g·cm-3,μ=1.320 mm-1,F(000)=974,R1=0.066 9,wR2=0.133 2(I2σ(I));具有环状双核锌(Ⅱ)连接的二维双层结构,双层之间又进一步通过O-H…O氢键组装成三维超分子结构。此外,该配合物具有较好的热稳定性和发光性能。     

Porous F-doped BiVO4: Synthesis and enhanced photocatalytic performance for the degradation of phenol under visible-light illumination

Fluoride-doped BiVO₄ with the F/Bi molar ratios of 0, 0.09, 0.13, and 0.29 (denoted as BiVO₄–F0, BiVO₄–F0.09, BiVO₄–F0.13, and BiVO₄–F0.29, respectively) were synthesized using the hydrothermal strategy with the hydrothermally derived BiVO₄ as the precursor and NH₄F as the fluoride source. Physicochemical properties of the materials were characterized by means of a number of analytical techniques. Photocatalytic activities of the fluoride-doped BiVO₄ samples were evaluated for the degradation of phenol under visible-light irradiation. It is shown that compared to the undoped BiVO₄–F0 sample, the fluoride-doped BiVO₄ samples retained the monoclinic structure, but possessed higher surface areas and oxygen adspecies concentration, better light-absorbing performance, and lower bandgap energies. Among the four samples, the porous spherical BiVO₄–F0.29 sample exhibited the best photocatalytic activity for the degradation of phenol in the presence of a small amount of H₂O₂ under visible-light illumination. It is concluded that the higher surface area and oxygen adspecies concentration, stronger optical absorbance performance, and lower bandgap energy were responsible for the excellent photocatalytic performance of BiVO₄–F0.29 for the photocatalytic degradation of phenol.     

Formation of oxalate induced by 4,4’-Bipyridine: Hydrothermal sheses of two erbium coordination polymers

Two different erbium(III) 5-nitroisophthalate coordination polymers were prepared based on the adjustement of 4,4’-Bipyridine. Structural analysis indicated that the production of the bridging oxalate group (C₂O₄ ²⁻) may be attributed to the reductive coupling of CO₂ molecules from the decarboxylation of the 5-Nip²⁻ ligand (5-Nip²⁻—anion of 5-nitroisophthalic acid), which is induced by 4,4’-Bipyridine.     

N-Halo succinimide-promoted one-pot three-component electrophilic cyclization: Facile access to dihalogenated heterocycles under mild conditions

An effective and concise electrophilic cyclization of 1,4-butynediols, 4-aminobut-2-yn-1-ols, pent-2-yne-1,5-diols, 2-propynolphenols and 2-propynolanilines with N-halo succinimides and trimethylsilyl halides opens a one-pot synthetic access to five- and six-membered dihalogenated heterocycles in moderate to good yields. The optimized cyclization conditions are tolerated with many functional groups.     

A Novel Self-assembled Dodecameric Water Cluster Stabilized by a Citrate-Bridged Copper(Ⅱ) Compound

The crystal structure of [Cu₂(cit)(phen)₂]·6H₂O ( 1 ) (cit?citrate anion, phen?1,10‐phenanthroline) reveals an unusual hydrogen‐bonded water dodecamer. The centrosymmetric dodecamer contains a decameric core with two pensile monomers, which is described as a chair with two handles. The structure, being predicted to be relative stable to other dodecameric structures, is stabilized by hydrogen bonding with the carboxylate groups of citrate ligands. The variable‐temperature magnetic study of 1 shows weak antiferromagnetic interaction.     

基于5-(3',4'-二(四唑-5'-基)苯氧基)间苯二甲酸构筑的镧系金属配合物的合成、晶体结构及性质

在水热条件下利用H₂btpa配体合成了2个镧系金属配合物{[Ln(btpa)(H₂O)(OH)]·bpy}_n(Ln=Tb(1),Pr(2),H₂btpa=5-(3',4'-二(四唑-5'-基)苯氧基)间苯二甲酸,bpy=4,4'-联吡啶),并用元素分析、红外光谱、X射线粉末衍射、X射线单晶衍射对其进行了表征。配合物1和2中,双核镧系金属单元通过btpa2-配体以μ₄:η¹,η²,η¹,η²的配位模式连接,形成二维网状结构,客体分子4,4'-联吡啶通过分子间的氢键作用存在于结构中。相邻的二维网通过氢键的识别作用以锁链形式拓展为三维超分子结构。室温下配合物1呈现出Tb^Ⅲ的特征荧光发射峰。     

AgI/h-MoO_3异质结的构筑及其模拟燃油光催化氧化脱硫活性

利用沉积法获得了异质结AgI/h-MoO_3光催化剂,通过X射线衍射(XRD)、扫描电子显微镜(SEM)、光电子能谱(EDS)、X射线光电子能谱(XPS)、紫外-可见漫反射吸收光谱(UV-Vis-DRS)、光致发光(PL)、电化学阻抗(EIS)等方法对其物相组成、形貌、光吸收特性、光电化学性能等进行了表征。以噻吩的正辛烷溶液模拟催化裂化(FCC)汽油为探针考察了AgI/h-MoO_3光催化氧化脱硫活性,结果表明,AgI/h-MoO_3-18异质结在催化剂浓度为1.5 g·L~(-1),可见光照射2 h后,光催化氧化脱硫活性达98%。利用XRD、XPS、UV-Vis-DRS揭示了AgI/h-MoO_3光照后生成少量的金属Ag,使其结构转变为Z型AgI/Ag/h-MoO_3,有利于光生电子(e~-)转移。利用活性物种捕获实验、循环实验研究了AgI/h-MoO_3光催化氧化脱硫机理及其稳定性,实验结果表明:AgI/h-MoO_3不仅具有较高的光催化氧化脱硫活性,而且还有良好的稳定性。