Two novel quadrupolar organic compounds, 3-(4-((E)-2-(9-butyl-9H-carbazol-6-yl) vinyl)styryl)-9-propyl-9H-carbazole (BCSPC) and 3-(3-(3-((1E)-2-(4-((E)-2-(3-(3,5-bis(9-butyl-9H-carbazol-6-yl)phenyl)-9-butyl-9H-carbazol-6-yl)vinyl)phenyl) vinyl)-9-butyl-9H-carbazol-6-yl)-5-(9-butyl-9H-carbazol-6-yl)phenyl)-9-butyl-9H-carbazole (BCPBC), with different conjugated arms, have been designed and synthesized. Their one-and two-photon absorption (TPA) and excited fluorescence properties have been experimentally investigated. The two-photon absorption cross-sections of two compounds were estimated by two-photon excited fluorescence technique using 200 fs, 76 MHz, Ti:sapphire laser, which are 22 and 154 GM for BCSPC and BCPBC, respectively. The optimal excitation wavelengths are 780 nm for both BCSPC and BCPBC. A data recording experiment proved the potential application of the materials.
LI Lin1, YANG JiaXiang1,2, WANG CaiXia1, HU ZhangJun1, TIAN YuPeng1,2, LI Jing3, WANG ChuanKui3, LI Ming4, CHENG GuangHua4, TANG HuoHong5, HUANG WenHao5, TAO XuTang2 & JIANG MinHua2 1Department of Chemistry, Anhui University, Hefei 230039, China
Two new metal-centered ferrocene complexes Ni(SCN)2(L)4 (1) and Cu(OAc)2(L)2 (2) (L = 1-[1-ferro- cenylmethyl]imidazole) have been synthesized and characterized by elemental analysis, single crystal X-ray diffraction analysis, spectroscopic and cyclic voltammetric measurements. The geometry of Ni(Ⅱ) in 1 is octahedral, with four ligands in the equatorial plan and two thiocyanate anions at the axial site, while that of Cu(Ⅱ) in 2 is a distorted octahedron formed by two chealted OAc- and two ligands. Single crystal X-ray diffraction studies reveal that there is partial electron delocalization from ferrocene to imidazole in the two complexes. Electrochemical measurements exhibit that complexes 1 and 2 un-dergo similar reversible one electron redox processes, suggesting that the ferrocene moieties are equivalent and there are no interactions among them.
WANG XuChunWU JieYingZHOU HongPingTIAN YuPengLI LinYANG JiaXiangJIN BaoKangZHANG ShengYi
Two new coordination polymers [ZnLI2]∞ (1) and [CdLI2]∞ (2) (L: 3,6-di-(1,2,4-triazole-1-yl)-N-hexylcarbazole) were synthesized and their crystal structures were determined by single-crystal X-ray diffraction techniques.Complexes are both constructed with the helical chains along the 21 screw axis.The coordination bond,C-H···I weak interactions and π-πinteractions play significant roles in constructing their 3D or 2D frameworks.Two different DFT calculations are performed for the weak interactions between the helical chains of the three different coordination polymers ([ZnLI2]∞,[CdLI2]∞ and the reported [HgLI2]∞).The results reveal that weak interactions play important roles in these supramolecular systems of helical configuration,namely,the trend is the shorter H···I distance and π-π stacking distance,the stronger the intermolecular interactions.The photoluminescence of the complexes measured in the solid state at room temperature indicates that the emission intensity varies extensively,which can be rationalized by the heavy atom effect.
A novel hydrogen peroxide biosensor based on the BPT/AuNPs/graphene/HRP composite was developed. Firstly, graphene was prepared under the protection of polyvinylpyrrolidone (PVP), and then the AuNPs/graphene composite was synthesized via in situ decoration. Using biphenyldimethanethiol (BPT) as a connector, the AuNPs/graphene composite was immobilized on the surface of the Au electrode, and whereafter the horseradish peroxidase (HRP) was decorated on the surface of the composite by adsorption. The morphology and structure of the products were characterized by XRD, SEM, TEM and UV-visible spectroscopy. The electrocatalytic performance of the resulting BPT/AuNPs/grapheme/HRP composite (namely, biosensor) was studied by electrochemical instrument. The results show that the biosensor has high sensitivity and fast response to H2O2. In the solution of pH 7.4 with potential -0.2V, the linear response of the biosensor to H2O2 ranges from 5.0×10-6 to 2.5×10-3M with the detection limit of 1.5×10-6M.
WANG TengZHU YiLI GaiZHANG ShengYiSONG JiMingMAO ChangJieWU JieYingJIN BaoKangTIAN YuPeng
The cantaloupe-like particles of CeOHCO_3 were synthesized in aqueous solution by using cetyltrimethylammonium bromide (CTAB) as soft template. Then, the bunchiness rods of CeO_2 were obtained by calcining CeOHCO_3 at 450 ℃. The results of thermogravimetric/differential thermal analysis reveal that an endothermic reaction with decomposition is involved in the transformation process from CeOHCO_3 to CeO_2. By scanning electron microscopy and X-ray diffraction analysis, it is found that the orthorhombic phase CeOHCO_3 particles are constituted of short nanorods with diameters ranging from several tens nm to over 100 nm, and the cubic phase CeO_2 rods are composed of small particles with diameter ca. 15 nm. From the results of UV-Vis absorption and photoluminescence analysis, it is found that the CeO_2 possess abundant defects, and the band gaps of the CeO_2 and CeOHCO_3 are ca. 2.70 eV and 3.87 eV, respectively.
Three bis-vinylpyridine compounds (4,4′-bis(2-vinylpyridine)biphenyl L1,4,4′-bis(3-vinylpyridine) biphenyl L2,and 4,4′-bis (4-vinylpyridine)biphenyl L3) were synthesized by one-step solid-state reactions at room temperature,giving nearly quantitative yields. The compounds obtained were fully characterized by IR,MS and NMR spectroscopies. The structures of L2 and L3 were determined by single crystal X-ray diffraction analysis. No noticeable solvatochromism was observed in either one-photon absorption or one-photon excited fluorescence spectra. All of the compounds have high fluorescence quantum yields and long fluorescence lifetime. The linear and nonlinear optical properties of the compounds were investigated both experimentally and theoretically. Interestingly,the position of the nitrogen atom from pyridine influences their two-photon absorption across-sections.
