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1.
将具有不同端基的硫脲基团与三苯基磷组分结合,利用所得到的配体合成了2个具有NSP(氮硫磷)鳌合位点的钴-硫脲化合物,并研究了其光解水产氢性能。配合物[Co(L2)(L2'')](BF42.5·H2O·0.5C2H5OH (2)(L2=(2-二苯基膦-苯烯基)-氨基硫脲腙-罗丹明6G,L2''=(2-二苯基膦氧-苯烯基)-氨基硫脲腙-罗丹明6G)通过引入罗丹明荧光团与光敏剂分子协同作用,其产氢TON值可以达到2 800 molH2·molcat-1,其初始TOF值可达到930 molH2·molcat-1·h-1。相同条件下,相比于配合物[Co(L1)(L1'')](BF4)·0.5H2O (1)(L1=(2-二苯基膦-苯烯基)-氨基硫脲腙-硫甲基,L1''=(2-二苯基膦氧-苯烯基)-氨基硫脲腙-硫甲基),提高了体系的催化活性,可能是由于荧光素分子与配合物2之间的分子间π-π堆积作用有利于光敏剂和光催化剂之间的光致电子转移。  相似文献   

2.
通过溶剂热和水热合成的方法制备了2个Cd(Ⅱ)配位聚合物[Cd2(L)(DMF)1.5(H2O)2]n1)和{[Cd(L)0.5(4,4''-bpy)(H2O)]·2H2O}n2)(H4L=5,5''-(己烷-1,6)-双-(氧基)-二-间苯二甲酸)。结构分析表明配合物1是一个(4,4)-连接的sql拓扑网络,拓扑符号为{44·62}2。配合物2是一个(4,4,4)-连接的三重穿插的bbf网络,拓扑符号为(66)(64·82)。配合物12都呈现出较好的热稳定性和荧光性质。  相似文献   

3.
通过溶剂热和水热合成的方法制备了2个Cd(Ⅱ)配位聚合物[Cd2(L)(DMF)1.5(H2O)2]n1)和{[Cd(L)0.5(4,4''-bpy)(H2O)]·2H2O}n2)(H4 L=5,5''-(己烷-1,6)-双-(氧基)-二-间苯二甲酸)。结构分析表明配合物1是一个(4,4)-连接的sql拓扑网络,拓扑符号为{44·62}2。配合物2是一个(4,4,4)-连接的三重穿插的bbf网络,拓扑符号为(66)(64·82)。配合物12都呈现出较好的热稳定性和荧光性质。  相似文献   

4.
将具有NN(氮氮)双齿配位点的席夫碱配体L2(L2=1,4-苯二-2''-吡啶腙)与镍构筑得到一例[2+2]型金属有机大环[Ni2(L2)2(CH3CN)4](ClO44·4CH3CN(2),并将其用于可见光条件下的光解水产氢研究。该非贵金属光催化体系由催化剂、光敏剂(荧光素,Fl)和电子牺牲剂(三乙胺)三部分组成。相比于具有相同配位环境的单核配合物[Ni(L1)2(CH3CN)2](ClO421,L1=3-甲酰基苯-2''-吡啶腙),金属有机大环2作为催化剂具有较高的光催化活性,其产氢TON值可以达到3 100 molH2·molcat-1,归因于荧光素分子可能与金属有机大环2形成超分子配合物,提高了光致电子转移效率。  相似文献   

5.
设计合成了3种新颖的金属有机配合物(MOCs):{[Pb2(HL)(phen)]·2H2O}n1),{[Ni(H3L)(4,4''-bipy)1.5(H2O)4]·6H2O}n2)和{[Ni2(HL)(1,4-bibb)(H2O)]·(CH3CN)·H2O}n3)(H5L=3,5-二(2'',5''-苯二羧酸)苯甲酸,phen=1,10-菲咯啉,4,4''-bipy=4,4''-联吡啶,1,4-bibb=1,4-二(苯并咪唑)苯),并通过单晶X射线衍射、红外光谱(IR)、热重分析(TG)和粉末衍射对它们进行结构表征。结构分析表明1是基于[Pb2μ2-COO)2μ1-COO)4]SBUs的一维链状结构;2是二维层状结构,其拓扑符号为{4.62}2{42.62.82};3是一个3D网络结构,其拓扑符号为{62.84}{64.82}2。进一步研究了配合物荧光和磁性能。荧光检测显示,配合物1在水溶液中可以高灵敏识别Fe3+和Cr2O72-离子。同时研究了配合物1对Fe3+和Cr2O72-猝灭机理。磁性分析表明配合物3中的Ni(Ⅱ)离子之间存在反铁磁相互作用。  相似文献   

6.
荣介伟  章文伟 《无机化学学报》2018,34(12):2307-2315
以柔性1,3,5-三(4-羧酸苯氧基)苯(H3TCPB)为配体,以4,4''-联吡啶(4,4''-BPY)为辅助配体,在溶剂热条件下合成了2个新颖的分别具有三核锌簇和三核钴簇的金属有机骨架化合物:{[Zn3(TCPB)2(4,4''-BPY)]·DMF·3H2O}n1)和{[Co1.5(TCPB)(DMF)(H2O)]·DMF}n2),通过单晶X射线衍射,红外光谱,元素分析,热重分析和粉末X射线衍射对其结构进行了表征。单晶X射线衍射分析表明化合物1属于三斜晶系,P1空间群,表现出三维(3,8)连接的网状结构,拓扑符号为:{43}2·{46·618·84}·{6};化合物2也属于三斜晶系,P1空间群,为二维(3,6)连接的网络层状结构,拓扑符号为:{43}4·{46·618·84}。此外,荧光性质研究表明固态化合物1在室温条件下发射出源于TCPB3-和4,4''-BPY配体的淡蓝色荧光,而化合物2在相似的条件下没有荧光发射。  相似文献   

7.
以2-(4''-羧基苯基)咪唑-4,5-二羧酸(H4CPhIDC,C12H8N2O6)为配体,用溶剂热合成了3种配位聚合物{[Cd2(CPhIDC)(bimb)]·H2O}n1)、{[Cd2(CPhIDC)(phen)2]·3H2O}n2)、{[Zn2(CPhIDC)(bpp)]·1.5H2O}n3)(bimp=1,4-双咪唑基-丁烷,phen=1,10-菲咯啉,bpp=1,3-双(4-吡啶基)-丙烷)。用元素分析、红外光谱、粉末X射线衍射和单晶X射线衍射对配合物进行了表征和结构分析。结构分析表明,主配体以完全去质子化CPhIDC4-的形式与中心金属离子形成以μ4μ5为配位模式的二维及三维聚合物。配合物13是三维网络结构,同时呈现(3,4,5)-连接的(5·6·7)(4·52·6·72)(4·52·6·74·82)拓扑结构,两者的不同之处是中心离子和辅助配体。配合物2是二维波纹状渔网结构,呈现44·62拓扑结构,在其空间填充上又类似于DNA双螺旋链的单螺旋结构。测定了产物的固体荧光光谱;用EtBr荧光探针法研究了配体及配合物与ct-DNA的相互作用。  相似文献   

8.
在水热条件下利用H4ddb配体合成了3个过渡金属配合物[Co2(ddb)(phen)2(H2O)6]·3H2O(1),[Co(ddb)0.5(bpy)0.5(H2O)3]n2)和{[Ag(dpe)]·0.5(H2ddb)·H2O}n3)(H4ddb=3,3'',4,4''-四羧基偶氮苯,bpy=4,4''-联吡啶,dpe=1,2-二(4-吡啶基乙烯)),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为双核结构,基于丰富的氢键作用扩展形成三维超分子网结构。配合物2为基于钴离子通过ddb4-配体以μ4η1,η1,η1,η1的配位模式连接而成的二维网结构。配合物3是由Ag(Ⅰ)离子与dpe配体形成的直链结构,客体分子H2ddb2-通过氢键作用将其扩展为三维超分子结构。此外还研究了配合物1~3的荧光性质和热稳定性。  相似文献   

9.
合成了2个镉(Ⅱ)金属有机骨架化合物{[Cd(L)(fma)]·0.5H2O}n1)和{[Cd(L)0.5(sdb)]·DMF}n2)(L=E,E-2,5-二己氧基-1,4-双(2-乙烯-吡啶基)苯,H2fma=延胡酸,H2sdb=4,4''-磺酰基二苯甲酸),研究了它们在金属离子和有机分子的发光传感中的应用。结果表明,Fe3+对配位聚合物12的发光强度有明显的猝灭作用。此外,聚合物12还对水杨醛具有明显的猝灭能力。  相似文献   

10.
设计、合成了2个配合物:{[Co2(pddb)2μ2-H2O)(H2O)2]·2DMA·5H2O}n1)和{[Ni2(pddb)2μ2-H2O)(H2O)2]·2DMA·5H2O}n2)(H2pddb=3,3''-(吡啶-3,5)二苯甲酸,DMA=N,N-二甲基乙酰胺),并通过红外光谱(IR),元素分析,热重分析(TG)和单晶X射线衍射确定它们的结构。结构分析表明12是异质同构的,其空间构型可简化成(3,6)连接的拓扑结构,其符号为(42·6)·(44·62·88·10)。进一步研究了配合物12的固体紫外、磁性及其催化性能。研究表明12中的中心金属离子之间存在反铁磁耦合作用,并且1可以作为C-H活化的高效非均相催化剂。  相似文献   

11.
娄太平  张乐  郭军兴 《化学学报》2010,68(6):466-470
研究了在不同温度下的NaNO3和AgNO3水溶液中Li1.3Ti1.7Al0.3(PO4)3和Na1.3Ti1.7Al0.3(PO4)3离子交换行为.实验表明Li1.3Ti1.7Al0.3(PO4)3和Na1.3Ti1.7Al0.3(PO4)3均显示出了高选择性与Na+和Ag+进行离子交换的特征,且对Ag+的选择性高于Na+.升高温度可显著提高Ag/Li和Ag/Na的交换反应速度.  相似文献   

12.
Single crystals of K3RESi2O7 (RE=Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) were grown from a potassium fluoride flux. Two different structure types were found for this series. Silicates containing the larger rare earths, RE=Gd, Tb, Dy, Ho, Er, Tm, Yb crystallize in a structure K3RESi2O7 that contains the rare-earth cation in both a slightly distorted octahedral and an ideal trigonal prismatic coordination environment, while in K3LuSi2O7, containing the smallest of the rare earths, lutetium is found solely in an octahedral coordination environment. The structure of K3LuSi2O7 crystallizes in space group P63/mmc with a=5.71160(10) Å and c=13.8883(6) Å. The structures containing the remaining rare earths crystallize in the space group P63/mcm with the lattice parameters of a=9.9359(2) Å, c=14.4295(4) Å, (K3GdSi2O7); a=9.88730(10) Å, c=14.3856(3) Å, (K3TbSi2O7); a=9.8673(2) Å, c=14.3572(4) Å, (K3DySi2O7); a=9.8408(3) Å, c=14.3206(6) Å, (K3HoSi2O7); a=9.82120(10) Å, c=14.2986(2) Å, (K3ErSi2O7); a=9.80200(10) Å, c=14.2863(4) Å, (K3TmSi2O7); a=9.78190(10) Å, c=14.2401(3) Å, (K3YbSi2O7). The optical properties of the silicates were investigated and K3TbSi2O7 was found to fluoresce in the visible.  相似文献   

13.
The near infrared spectra of aqueous solutions of the ethylsulfates of La, Nd, Gd, Tb, Er, Yb, Lu, Y, and Na have been determined from about 0.2 mol-dm–3 to nearly saturation. The extinction coefficients of water have been calculated taking into account the absorption of ethylslfate anions determined in separate experiments. Their values appeared to be nearly the same as that of pure water. The relative contents of free OH groups in 0.5 and 0.7M solutions have been estimated from the absorbances at 1160 nm. They were lower in solutions of the heavy rare-earth ethylsulfates (Tb, Er, Yb, Lu) than in equimolar solutions of the lighter ones (La, Nd), confirming our previous view that secondary hydration of the heavy trivalent rare-earth cations is distinctly stronger than that of the lighter ones. A comparison of the spectra of these aqueous ethylsulfates with those of perchlorates shows that the structure-breaking ability of the C2H5SO 4 ion is much smaller than that of perchlorate anion.  相似文献   

14.
针对银精矿样品复杂,难消解的特点,研究了不同酸溶法和碱熔法对样品的消解情况,建立了硝酸,盐酸,氢氟酸,高氯酸消解银精矿的方法。根据元素灵敏度和抗干扰性,选定各元素的测定波长。通过酸溶样和碱熔样测定结果比对,验证了方法准确性。建立了四酸消解-电感耦合等离子体光谱法测定银精矿中铜、铅、锌、砷、镉、钙、镁、锰含量的方法,元素的线性相关系数均在0.9999以上。通过共存元素干扰实验,确定了银精矿中高含量元素(铜、铅、锌、铁、锑、铋等)对测定元素结果没有影响。方法检出限:Cu 0.0063 mg/L, Pb 0.0159 mg/L ,Zn 0.0090 mg/L,As 0.0192 mg/L, Cd 0.0093 mg/L ,Ca 0.0084 mg/L, Mg 0.0075 mg/L, Mn 0.0081 mg/L。测定下限:Cu 0.0105mg/L,Pb 0.0265 mg/L, Zn 0.0150 mg/L, As 0.0320 mg/L, Cd 0.0155 mg/L, Ca 0.0140 mg/L, Mg 0.0125 mg/L,Mn 0.0135 mg/L。3个样品的相对标准偏差在0.87%~3.56%之间,加标回收率在95.00%~103.56%之间。方法流程短,操作简单,快速,灵敏度和再现性高,结果准确可靠,可以满足银精矿中铜、铅、锌、砷、镉、钙、镁、锰含量的测定。  相似文献   

15.
The room temperature structures of the five layer Aurivillius phases A2Bi4Ti5O18 (A=Ca, Sr, Ba and Pb) have been refined from powder neutron diffraction data using the Rietveld method. The structures consist of [Bi2O2]2+ layers interleaved with perovskite-like [A2Bi2Ti5O16]2− blocks. The structures were refined in the orthorhombic space group B2eb (SG. No. 41), Z=4, and the unit cell parameters of the oxides are a=5.4251(2), b=5.4034(1), c=48.486(1); a=5.4650(2), b=5.4625(3), c=48.852(1); a=5.4988(3), b=5.4980(4), c=50.352(1); a=5.4701(2), b=5.4577(2), c=49.643(1) for A=Ca, Sr, Ba and Pb, respectively. The structural features of the compounds were found similar to n=2-4 layers bismuth oxides. The strain caused by mismatch of cell parameter requirements for the [Bi2O2]2+ layers and perovskite-like [A2Bi2Ti5O16]2− blocks were relieved by tilting of the TiO6 octahedra. Variable temperature synchrotron X-ray studies for Ca and Pb compounds showed that the orthorhombic structure persisted up to 675 and 475 K, respectively. Raman spectra of the compounds are also presented.  相似文献   

16.
Tao Lin  Wei Li  Maochu Gong  Yao Yu  Bo Du  Yaoqiang Chen   《Acta Physico》2007,23(12):1851-1856
TiO2,ZrO2-TiO2,andZrO2-TiO2-CeO2 were prepared by co-precipitation method and characterized by X-ray diffraction (XRD), specific surface area measurements (BET), temperature programmed desorption (NH3-TPD), oxygen storage capacity (OSC), and temperature programmed reduction (H2-TPR). The results showed that ZrO2-TiO2-CeO2 exhibited large number of surface strong acid, possessed some oxygen storage capacity, and strong redox property. The three materials were used as supports and the monolith catalysts were prepared with 1% (w) V2O5 and 9% (w)WO3 for selective catalytic reduction (SCR) of NO with ammonia in the presence of excessive O2, and the results of catalytic activity showed that the catalyst used ZrO2-TiO2-CeO2 as support yielded nearly 100% NO conversion at 275 °C at a gas hourly space velocity (GHSV) of 10000 h−1, and it had the best catalytic activity and showed great potential for practical application.  相似文献   

17.
The crystal structures of Bi2.5Na0.5Ta2O9 and Bi2.5Nam-1.5NbmO3m+3 (m=3,4) have been investigated by the Rietveld analysis of their neutron powder diffraction patterns (λ=1.470 Å). These compounds belong to the Aurivillius phase family and are built up by (Bi2O2)2+ fluorite layers and (Am-1BmO3m+1)2- (m=2-4) pseudo-perovskite slabs. Bi2.5Na0.5Ta2O9 (m=2) and Bi2.5Na2.5Nb4O15 (m=4) crystallize in the orthorhombic space group A21am, Z=4, with lattice constants of a=5.4763(4), b=5.4478(4), c=24.9710 (15) and a=5.5095(5), b=5.4783(5), c=40.553(3) Å, respectively. Bi2.5Na1.5Nb3O12 (m=3) has been refined in the orthorhombic space group B2cb, Z=4, with the unit-cell parameters a=5.5024(7), b=5.4622(7), and c=32.735(4) Å. In comparison with its isostructural Nb analogue, the structure of Bi2.5Na0.5Ta2O9 is less distorted and bond valence sum calculations indicate that the Ta-O bonds are somewhat stronger than the Nb-O bonds. The cell parameters a and b increase with increasing m for the compounds Bi2.5Nam-1.5NbmO3m+3 (m=2-4), causing a greater strain in the structure. Electron microscopy studies verify that the intergrowth of mixed perovskite layers, caused by stacking faults, also increases with increasing m.  相似文献   

18.
K3InF6 is synthesized by a sol-gel route starting from indium and potassium acetates dissolved in isopropanol in the stoichiometry 1:3, with trifluoroacetic acid as fluorinating agent. The crystal structures of the organic precursors were solved by X-ray diffraction methods on single crystals. Three organic compounds were isolated and identified: K2InC10O10H6F9, K3InC12O14H4F18 and K3InC12O12F18. The first one, deficient in potassium in comparison with the initial stoichiometry, is unstable. In its crystal structure, acetate as well as trifluoroacetate anions are coordinated to the indium atom. The two other precursors are obtained, respectively, by quick and slow evaporation of the solution. They correspond to the final organic compounds, which give K3InF6 by decomposition at high temperature. The crystal structure of K3InC12O14H4F18 is characterized by complex anions [In(CF3COO)4(OHx)2](5−2x)− and isolated [CF3COOH2−x](x−1)− molecules with x=2 or 1, surrounded by K+ cations. The crystal structure of K3InC12O12F18 is only constituted by complex anions [In(CF3COO)6]3− and K+ cations. For all these compounds, potassium cations ensure only the electroneutrality of the structure. IR spectra of K2InC10O10H6F9 and K3InC12O12F18 were also performed at room temperature on pulverized crystals.  相似文献   

19.
通过调节B2O3‐Bi2O3‐ZnO‐Al2O3(BBZA)玻璃的添加量研究其对钛酸钡(BaTiO3)陶瓷烧结条件、晶体结构和介电性能的影响。结果表明:添加适量的BBZA玻璃能够有效地将BaTiO3陶瓷烧结温度由1350℃降至950℃,并使其致密化。同时,添加BBZA玻璃后,BaTiO3的晶体结构随着烧结温度的升高而发生转变(立方相→四方相)。另外,BBZA玻璃的引入使BaTiO3陶瓷的居里峰得到了有效的抑制和拓宽。陶瓷微观形貌显示,玻璃相均匀分布在BaTiO3晶粒表面。优化的BaTiO3陶瓷制备条件如下:BBZA添加量(质量分数)为2.0%,烧结温度为950℃。在该条件下制备的BaTiO3陶瓷介电常数达到1364,介电损耗低至1.2%。  相似文献   

20.
通过调节B2O3-Bi2O3-ZnO-Al2O3(BBZA)玻璃的添加量研究其对钛酸钡(BaTiO3)陶瓷烧结条件、晶体结构和介电性能的影响。结果表明:添加适量的BBZA玻璃能够有效地将BaTiO3陶瓷烧结温度由1 350℃降至950℃,并使其致密化。同时,添加BBZA玻璃后,BaTiO3的晶体结构随着烧结温度的升高而发生转变(立方相→四方相)。另外,BBZA玻璃的引入使BaTiO3陶瓷的居里峰得到了有效的抑制和拓宽。陶瓷微观形貌显示,玻璃相均匀分布在BaTiO3晶粒表面。优化的BaTiO3陶瓷制备条件如下:BBZA添加量(质量分数)为2.0%,烧结温度为950℃。在该条件下制备的BaTiO3陶瓷介电常数达到1 364,介电损耗低至1.2%。  相似文献   

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