Ni/γ-Al2O3催化剂的2-MF气相加氢合成2-MTHF性能研究

2-甲基四氢呋喃(2-MTHF)是极具市场潜力的生物燃料、绿色溶剂和化学中间体.采用浸渍法制备Ni/γ-Al2O3催化剂,在固定床反应器评价其2-甲基呋喃(2-MF)气相加氢合成2-甲基四氢呋喃(2-MTHF)反应性能.通过XRD、N2等温吸附-脱附、H2-TPR、NH3-TPD、TEM、H2吸附和XPS对催化剂结构和表面性质进行表征,研究Ni负载量、焙烧温度和反应条件对催化剂性能的影响规律.结果表明:Ni/γ-Al2O3催化剂的Ni金属面积、晶粒尺寸、反应温度和压力都会影响2-MF的转化率;孔结构、酸量和反应温度是影响2-MTHF选择性的主要原因,平均孔径大、酸量大和适宜的反应温度有利于提高2-MTHF选择性. 400℃焙烧的负载量为15%的Ni/γ-Al2O3催化剂, Ni金属面积大、晶粒尺寸小、总酸量多,催化剂表面的金属活性中心与酸性中心协同作用促进了2-MF呋喃环上C=C加氢生成2-MTHF,性能较优.在2 MPa、100℃、WHSV=2.7 h-1、H2/2-MF=6.4的条件下,该催化剂上2-MF转化率为99.8%, 2-MTHF选择性为98.0%,催化剂可以稳定运行40 h.     

新型双核配位聚合物Ni2（A`B`T`C`）（phen）2（H2O）4·4H2O的合成及其晶体结构

以A`B`T`C`(2,2’,3,3’-偶氮苯四甲酸)和Phen(邻啡啰啉)为配体,采用溶剂挥发法合成了一种新型双核配位聚合物Ni2(A`B`T`C`)(phen)2(H2O)4.4H2O(1),其结构经X-射线单晶衍射和元素分析表征。1属三斜晶系,空间群P-1,晶胞参数a=9.432(11),b=10.697(12),c=10.751(12),α=87.946(17)°,β=67.756(15)°,γ=76.085(16)°,V=972.6843,Z=12,Dc=4.740 mg.cm-3,μ=4.039 mm-1,F(000)=1 364,R1=0.042 5,ωR2=0.132 9。1中Ni(Ⅱ)与A`B`T`C中的两个羧基氧原子,两个H2O中的两个氧原子和phen中的两个氮原子配位,形成一个畸变的八面体几何构型。Ni(Ⅱ)经配体A`B`T`C桥联形成一维链,链与链之间又通过氢键堆积成三维超分子结构。     

簇合物{[Ni(enMe)2][SiW12O40]}[Ni(enMe)2(H2O)2]2·3H2O的水热合成及晶体结构

用水热法合成出一种新的一维链状簇合物{[Ni(enMe)2][SiW12O40]}[Ni(enMe)2(H2O)2]2·3H2O, 并对其进行了元素分析、IR谱、TGA及X射线单晶衍射等系列表征. 该晶体属于单斜晶系, 空间群C2/c, a=1.2656 nm, b=2.20656(4) nm, c=2.26763(4) nm, β=92.078°, V=6.32852(16) nm3, Z=4, Dc=3.801 g/cm3, μ=2.271 mm-1, F(000)=6512, R1=0.0549, wR2=0.1087. 在该化合物中, 具有α-Keggin结构的聚阴离子簇[SiW12O40]6-之间通过配位阳离子[Ni(enMe)2]2+桥连成一维无限链状结构, 另一种配位阳离子[Ni(enMe)2(H2O)2]2+和水分子填充在结构中, 通过分子间的氢键作用将该化合物拓展为三维网状结构.     

新型层状磷酸铝[Al6P8O32][(C2H5)2NHCH2CH2NH3]2·[C2H5NH2CH2CH2NH2C2H5] 的合成、表征及其共模板作用

在溶剂热体系中,以N,N-二乙基乙二胺为结构导向剂,合成了Al/P为3/4的层状磷酸铝[Al6P8O32][(C2H5)2NHCH2CH2NH3]2·[C2H5NH2CH2CH2NH2C2H5]单晶,并通过X射线单晶衍射结构分析.XRD,ICP,元素分析,差热-热重分析等手段进行了表征.该化合物属单斜晶系,P2(1)/c空间群,晶胞参数:a=0.90945(2)nm,b=1.46424(4)nm,c=1.87572(5)nm,β=102.672(2)°,Z=4.其阴离子层由AlO4四面体和PO3(=O)四面体单元交替连接构成,形成四、六、八元环拓扑结构,无机层以ABAB方式堆积,两种质子化的有机胺分子N,N-二乙基乙二胺及其重排产物N,N′-二乙基乙二胺填充在层间.用分子动力学模拟方法,考察了标题化合物中有机胺与无机层间的相互作用,讨论了这两种有机胺的共模板作用.     

过渡金属氧化物(M2O5)+m=1,2(M=V, Nb, Ta)与C2H4气相反应机理的密度泛函研究

采用密度泛函理论研究了过渡金属钒族氧化物阳离子团簇(M2O5)+m=1,2(M=V, Nb, Ta)与C2H4气相反应机理. 反应为(M2O5)m++C2H4→(M2O5)m-1M2O4++C2H4O, 反应物先化合生成C—O键相连的化合物, 经过过渡态后M—O键断裂, 从而发生氧原子转移到碳氢化合物上的反应. 对于V2O5+与C2H4的反应, 存在经顺式和反式两种过渡态结构路径, 从能量上看, 经反式过渡态结构的路径更有利. 计算结果表明, 发生反应时C2H4与钒氧化物阳离子反应大量放热, 而与铌、钽氧化物阳离子反应却放热较少甚至不放热, 这与实验结果一致. 钒、铌、钽氧化物阳离子团簇发生氧转移反应活性不同的原因是金属-氧键的强弱不同所致.     

吡啶配位的夹心型杂多阴离子{[Na(H2O)2]3[Ni(C5H5N)]3(AsW9O33)2}9-的结构及磁学性质

The pyridine coordinated sandwich-type heteropolytungstate Na7[Ni（H2O）6] { [Na（H2O）2]3[Ni（C5H5N）]3（AsW9O33）2}·28H2O was obtained by the reaction of Na2WO4·2H2O, NaAsO2 and pyridine with NiCl2·6H2O at pH =7.0 and characterized by elemental analysis, IR, UV-Vis,^1H NMR spectra and magnetic measurement. The structure of this heteropolytungstate was determined by X-ray diffraction analysis, which crystallized in triclinic system, space group P1 with a= 1.3153（9） nm, b= 1.7228（12） nm, c=2.6866（19） nm, a=74.130（11）°,β=78.032（12）°, γ = 73.179（12）° and Z= 2, R1 = 0.0604, wR2 = 0.0915 [I〉 2σ（I）]. Polyanion {[Na（H2O）2]3[Ni（C5H5N）]3（AsW9O33）2}^9- has approximately C3 symmetry, and three pyridine coordinated Ni（C5H5N）^2＋ and three Na（H2O）2^＋ are encapsulated between two AsW9O33^9- . Magnetic measurements show that central Ni3 unit in the polyanion exhibits ferromagnetic Ni-Ni exchange interactions （J=6.17 cm^-1）.     

一个三羧酸配体构筑的铽金属-有机框架材料及对小分子溶剂的荧光识别

以3-羟基-5-(3,5-二甲酸-苯氧基)苯甲酸(H_3L)为配体,在溶剂热条件下与硝酸铽反应得到1个具有二维平面结构的镧系金属-有机框架材料(Tb-MOF):{[TbL(H_2O)]·3H_2O·DMF}n。单晶X射线衍射分析表明,Tb-MOF为正交晶系Ibca空间群。2个Tb(Ⅲ)离子通过6个羧基桥联形成双核[Ln_2(COO)_6]次级结构单元,晶体由[Ln_2(COO)_6]次级结构单元相互连接形成具有左手或右手螺旋结构的一维无机链,左手螺旋链与右手螺旋链通过配体L~(3-)相连形成二维层状结构。有机小分子溶剂交换荧光研究表明,TbMOF在硝基苯溶剂中表现出荧光猝灭现象,Tb-MOF材料对硝基苯等爆炸物具有潜在良好的荧光探测功能。     

[Ni(qina)2(H2O)2]·2DMSO配合物的合成、结构及其催化性能

在常温下, 通过溶剂置换法制备了[Ni(qina)2(H2O)2]·2DMSO单晶, 其中qina-为喹哪啶酸根, DMSO为二甲亚砜. 配合物属于单斜晶系, C2/m空间群. 2个qina-配体以氮原子和氧原子与Ni(Ⅱ)离子反式螯合配位, 2个H2O分子则以氧原子与Ni(Ⅱ)离子轴向配位, 形成八面体配合物. 配合物分子之间通过氢键和π-π堆积等弱相互作用构筑成三维超分子结构. 该配合物能显著提高乙酸-1-萘酯的水解反应速率, 当配合物浓度为1.0×10-4 mol/L时, 在pH=8.44的乙酸-1-奈酯体系中, 酯的水解速率提高了365倍.     

镍基彩色电沉积Cu_2O椭圆偏振光谱研究

应用电化学方法在Ni基底上沉积Cu2O彩色膜层以期提高装饰效果.X光电子能谱(XPS)、扫描电子显微镜(SEM)和能量色散谱(EDS)测试表明,膜层由Cu2O组成,沉积层光滑平整,且Cu2O层均匀覆盖Ni基底.椭圆偏振光谱表征不同沉积时间的膜层,提出膜层内存在由Ni逐渐变为Cu2O的过渡层,建立"空气—Cu2O层—过渡层—Ni基底"4层膜模型,并借助梯度有效介质近似解析椭圆偏振光谱,得到不同沉积时间的膜层厚度以及厚度随时间线性增长关系.     

高容量正极材料0.08LiCo0.75Al0.25O2-0.92LiNiO2的合成与电化学性能研究

在恒定pH值下将层状钴铝双羟基复合金属氧化物(CoAl-LDH)均匀包覆在球状Ni(OH)2表面,与LiOH.H2O混合均匀后,经高温煅烧制得钴铝酸锂包覆镍酸锂0.08LiCo0.75Al0.25O2-0.92LiNiO2正极材料.电化学测试表明,0.08LiCo0.75Al0.25O2-0.92LiNiO2正极比容量高,具有良好的倍率性能和循环寿命,其0.1C放电比容量为211 mAh·g-1,0.5C放电比容量为195.6 mAh·g-1,3C放电比容量为161 mAh·g-1,0.5C 30周期循环后容量保持率为93.2%,明显优于LiNiO2和钴酸锂包覆镍酸锂0.08LiCoO2-0.92LiNiO2正极.     

基于3，4-吡啶二羧酸的二维层状聚合物的合成和晶体结构

A metal-organic coordination polymer {[La(PDC)(N-HPDC)]·H₂O}_n (1) (H₂PDC=pyridine-3,4-dicarboxylic acid) has been hydrothermally synthesized and structurally characterized by X-ray diffraction single-crystal structure determination, elemental analyses and IR spectroscopy. The complex crystallizes in the monoclinic system, space group P2₁/c with a=1.452 8(2) nm, b=0.681 59(11) nm, c=1.464 0(2) nm, β=94.270(2)°, V=1.445 6(4) nm³, D_c=2.243 Mg·m^-3, Z=4, M_r=488.14, F(000)=944, μ(Mo Kα)=3.015 mm^-1, R=0.031 0 and wR=0.076 2 for 2 424 observed reflections (I>2σ(I)). There are La-O-C-O-C-La double chains in the complex. The chelating carboxylate O atoms and pyridyl N atoms lead the compound to 2D layers structure, which is extended to 3D supramolecular architecture through intermolecular hydrogen bonds. It is interesting that the polymer containing one-dimensional channels. CCDC: 708868.     

A 2D Lanthanide-organic Framework Based on Inorganic Lanthanum（Ⅲ） Sulfate Skeletons：Synthesis,Structure,and Luminescence and Thermal Properties

A new lanthanum coordination polymer formulated as {[La2(pyda) 2(μ4-SO4) ·5H2O]· 2H2O}n(1,H2pyda = 2,6-pyridine-dicarboxylic acid) has been synthesized from the reaction of H2pyda with lanthanide nitrate in the presence of sulfate as a counter anion. The compound was characterized by elemental analysis,IR spectroscopy and X-ray single-crystal diffraction. It crystallizes in the orthorhombic system,space group Pna21,with a = 18.8558(19) ,b = 6.5831(7) and c = 18.7543(19) . The compound is a 2D hybrid,in which the La(Ⅲ) ions were doubly connected by the carboxylic group of pyda2-ligand to form the La(Ⅲ) dimer followed by being grafted into 1D zig-zag chains which are further connected into a 2D network containing {[La(SO4) ]+}n helical chains. The interchain hydrogen bonding and π-π stacking interactions extended the 2D networks into a 3D supramolecular edifice.     

A series of chiral coordination polymers containing helicals assembled from a new chiral (R)-2-(4'-(4'-carboxybenzyloxy)phenoxy)propanoic acid: syntheses, structures and photoluminescent properties

Ten new chiral coordination polymers, namely, [Ni(L)(H(2)O)(2)] (1), [Co(L)(H(2)O)(2)] (2), [Cd(L)(H(2)O)] (3), [Cd(L)(phen)] (4), [Mn(2)(L)(2) (phen)(2)]·H(2)O (5), [Cd(2)(L)(2)(biim-4)(2)] (6), [Zn(2)(L)(2)(biim-4)(2)] (7), [Cd(L)(pbib)] (8), [Cd(L)(bbtz)] (9) and [Cd(L)(biim-6)] (10), where phen = 1,10-phenathroline, biim-4 = 1,1'-(1,4-butanediyl)bis(imidazole), pbib = 1,4-bis(imidazole-1-ylmethyl)benzene, bbtz = 1,4-bis(1,2,4-triazol-1-ylmethyl)benzene, biim-6 = 1,1'-(1,6-hexanedidyl)bis(imidazole), and H(2)L = (R)-2-(4'-(4'-carboxybenzyloxy)phenoxy)propanoic acid, have been synthesized under hydrothermal conditions. Their structures have been determined by single-crystal X-ray diffraction analyses and further characterized by infrared spectra (IR), powder X-ray diffraction (PXRD), elemental analyses and thermogravimetric (TG) analyses. Compounds 1 and 2 exhibit similar 1D left-handed helical chains, which are further extended into 3D supramolecular structures through O-H···O hydrogen-bonding interactions, respectively. Compound 3 shows a 2D double-layer architecture containing helical chains. Compound 4 features two types of 2D undulated sheets with helical chains, which are stacked in an ABAB fashion along the c direction. Compound 5 possesses a 1D double chain ribbon structure containing unusual meso-helical chains, which is linked by π-π interactions into a 2D supramolecular layer. These layers are further extended by hydrogen-bonding interactions to form a 3D supramolecular assembly. Compounds 6 and 7 are isostructural and exhibit 2D (4(4))-sql networks with helical chains. Neighboring sheets are further linked by C-H···O hydrogen-bonding interactions to generate 3D supramolecular architectures. Compounds 8-10 are isostructural and display 3D 3-fold interpenetrating diamond frameworks with helical chains. The effects of coordination modes of L anions, metal ions and N-donor ligands on the structures of the coordination polymers have been discussed. The luminescent properties of 3, 4 and 6-10 have also been investigated in detail.     

三维无机-有机杂化微孔化合物Mn3(BTC)2(DMF)4的合成与结构

传统的沸石和分子筛微孔晶体材料是指以硅酸盐、硅铝酸盐、磷铝酸盐和无机金属磷酸盐为骨架的晶体材料．近年来,利用刚性和热稳定性较好的有机分子(如芳香多酸和多碱)和金属离子作为结构单元制备出了新型的无机一有机杂化微孔晶体材料．这类晶体材料能够在去除孔道中的溶剂分     

[Zn2(C7H8O6)2(bipy)2(H2O)2]·4H2O手性配位聚合物的合成与晶体结构

采用溶剂热技术合成了一种新型手性配位聚合物[Zn2(C7H8O6)2(bipy)2(H2O)2]·4H2O(C7H8O6=2,3-氧-异丙叉基-L-酒石酸根, bipy=4,4'-联吡啶), 并通过单晶X射线衍射结构分析、元素分析、热重分析以及红外光谱进行了表征. 结构分析数据表明, 该化合物属单斜晶系, C2空间群, 晶胞参数a=2.02334(14) nm, b=1.13896(4) nm, c=1.01094(6) nm, β=117.366(3)°, V=2.0689(2) nm3. 两个晶体学独立的Zn原子均为八面体构型, 其中Zn1原子赤道配位点被2个酒石酸根中的4个羧酸根氧螯合配位, 2个酒石酸根中剩下的4个羧酸根氧中的2个分别与2个Zn2原子连接形成无限一维链, Zn2原子的另外2个反式赤道配位点被2个水分子氧占据, 同时这两种Zn原子的轴向配位点均被4,4'-联吡啶的氮原子占据, 形成具有矩形格子[0.51165(3) nm×1.13896(5) nm]的二维层状结构, 游离的2个水分子通过氢键作用形成二聚体, 并与酒石酸根中未与Zn配位的羧酸氧连接, 把二维层状结构连接成三维网状的超分子结构.     

配位聚合物[Ni(cpna)(bpy)(H2O)]n的合成、晶体结构及磁性质

通过水热方法,采用H₂cpna(H₂cpna=5-(2′-carboxylphenyl))和bpy(bpy=2,2′-bipyridine)与Ni(OAc)₂·4H₂O反应,合成了一个具有二维结构的配位聚合物[Ni(cpna)(bpy)(H₂O)]_n (1),并对其结构和磁性质进行了研究。结构分析结果表明该聚合物的晶体属于单斜晶系,P2₁/c空间群。3个镍(Ⅱ)离子、3个cpna配体、3个2,2′-bpy配体和3个配位水分子形成了一个[Ni₃(cpna)₃(bpy)₃(H₂O)₃]环,这些环通过镍(Ⅱ)离子与cpna配体的配位作用形成了一个二维层状结构。层与层之间又通过π-π堆积作用形成了一个三维的配位框架。研究表明,该聚合物中相邻镍(Ⅱ)离子之间存在很弱的反铁磁相互作用。     

两个具一维水链的镧系配位聚合物的合成与晶体结构(英文)

以Ln2O3(Ln=Nd和La),2,2′-联吡啶-3,3′-二羧酸(bpdc),4,4′-联吡啶(bpy)为原料,采用溶剂热法合成了2个具有二维骨架结构的无机-有机杂化材料[Nd2(bpdc)3(H2O)2]·bpy·4H2O(1)和[La2(bpdc)3(H2O)4]·4H2O(2),通过IR和X-射线单晶衍射分析等手段对其结构进行了表征。晶体1属于单斜晶系,C2/c空间群,晶胞参数a=3.3104(7)nm,b=0.74812(15)nm,c=1.9848(4)nm,β=104.75(3)°。晶体2属于单斜晶系,C2/c空间群,晶胞参数a=2.6749(5)nm,b=0.71165(14)nm,c=2.0542(4)nm,β=92.70(3)°。在这2个配位聚合物中,晶体中的结晶水沿着b轴呈现一维无限有序排列,将化合物中二维的金属有机骨架通过氢键相连进而形成了三维超分子结构。     

基于2,4,6-吡啶三羧酸配体桥连的铁(Ⅱ)/镍(Ⅱ)配位聚合物的水热合成及结构表征

在水热反应条件下FeCl₂·6H₂O、2,4,6-吡啶三羧酸(H₃pyta)和NaOH反应合成了1种一维链状铁配位聚合物[Fe₃(pyta)₂(H₂O)₈] (1);同样条件下Ni(OAc)₂·4H₂O、2,4,6-吡啶三羧酸(H₃pyta)、NaOH和4-氨基-3,5-二(4-吡啶基)-1,2,4-三氮唑(abpt)反应合成了1种二维网状镍配合物[Ni₃(pyta)₂(abpt)₂(H₂O)₃]·2H₂O (2)。通过元素分析和红外光谱对这2个配位聚合物进行了表征。单晶结构表明：配合物1的晶体属于单斜晶系,Cc空间群;配合物2的晶体属于单斜晶系,P2₁/c空间群。在配合物1中,pyta^3-配体采取μ₂-和μ₄-pyta^3- 2种桥连模式将Fe原子连成了沿c轴方向延伸的Fe-pyta链。而在配合物2中,pyta^3-配体仅采取μ₂-桥连模式将Ni原子连成线型三核[Ni₃(pyta)₂]单元,这些三核单元进一步通过abpt辅助配体桥连成二维 (4,4)层状结构。     

Ni（bpy）（H2O）（V2O6）和[Ni（bpy）2]2（V6O17）的水热合成与晶体结构

用NiCl2·6H2O,2,2＇-联吡啶（bpy）,NH4VO3,WO3在443K下通过水热反应法得到了两种多钒酸镍配合物Ni（bpy）（H2O）（V2O6）（1）和[Ni（bpy）2]2（V6O17）（2）．单晶X射线衍射结果表明化合物（1）属于正交晶系,空间群为Pcα2（1）,晶胞参数为0=0．91704（18）nm,b=1．0519（2）nm,c=1．4336（3）nm,V=1．3830（5）nm^3,Z=4;化合物（2）属于单斜晶系,空间群为P2（1）／c,晶胞参数为α=1．5467（3）nm,b=1．4740（3）nm,c=1．0457（2）nm,β=91．99（3）°,V=2．3826（8）nm^3,Z=4．化合物（1）由2,2’-联吡啶修饰的二维[Ni（V2O6）（H2O）]∞电中性层构成,而化合物（2）则由2,2＇-联吡啶修饰的、呈正弦波浪状的[Ni：（V6O17）]∞二维电中性层构成．     

A bridge between pillared-layer and helical structures: a series of three-dimensional pillared coordination polymers with multiform helical chains

Rational self-assembly of a long V-shaped 3,3',4,4'-benzophenonetetracarboxylate (bptc) ligand and metal salts in the presence of linear bidentate ligand yield a series of novel pillared helical-layer complexes, namely, [Cu2(bptc)(bpy)2] (1), [M3(Hbptc)2(bpy)3(H2O)4].2 H2O (M = Fe(2) and Ni(3)), [Co2(bptc)(bpy)(H2O)].0.5 bpy (4), [Cd2(bptc)(bpy)(H2O)2].H2O (5), [Mn2(bptc)(bpy)1.5(H2O)3] (6) and [M2(bptc)(bpy)0.5(H2O)5].0.5 bpy (M = Mn(7), Mg(8) and Co(9), bpy=4,4'-bipyridine). Their structures were determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectra, and thermogravimetric (TG) analyses. The structure of 1 consists of two types of chiral layers, one left-handed and the other right-handed, which are connected by bpy pillars to generate a novel 3D open framework featuring four distinct helical chains. Compounds 2 and 3 are isostructural and feature 3D structures formed from the interconnection of arm-shaped helical layers with bpy pillars. Compound 4 is a pillared helical double-layer complex containing four different types of helices, among which the nine-fold interwoven helices constructed from triple-stranded helical motifs are unprecedented. Compound 5 exhibits a novel 3D covalent framework which features nanosized tubular channels. These channels are built from helical layers pillared by bptc ligands. The structure of 6 is constructed from {Mn(bptc)(H2O)}n2n- layers, which consist of left- and right-handed helical chains, pillared by [Mn2(bpy)3(H2O)4]4+ complexes into a 3D framework. To the best of our knowledge, compounds 1-6 are the first examples of pillared helical-layer coordination polymers. Compounds 7-9 are isostructural and exhibit interesting 2D helical double-layer structures, which are constructed from {M(bptc)(H2O)2}n2n- ribbons cross-linked by [M2(bpy)(H2O)6]4+ complexes. Furthermore, the 3D supramolecular structures of 7-9 are similar to the 3D structure of 6, and the 2D structure of 7 can be transformed into the 3D structure of 6 at higher reaction temperature. By inspection of the structures of 1-9, it is believed that the V-shaped bptc ligand and V-shaped phthalic group of the bptc ligand are important for the formation of the helical structures. The magnetic behavior of compounds 1, 2, 4, 6, and 9 was studied and indicated the existence of antiferromagnetic interactions. Moreover, compound 5 shows intense photoluminescence at room temperature.