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2017 Volume 33 Issue 6
2017, 33(6): 913-922
doi: 10.11862/CJIC.2017.126
Abstract:
Two cobalt complexes containing NSP (nitrogen-sulphur-phosphor) chelator prepared from thiose-micarbazone ligands with different terminal functional groups and triphenylphosphine moiety have been synthesized in high yield and characterized. Their photocatalytic activity for hydrogen evolution under visible light irradiation was investigated. The photocatalyst [Co(L2)(L2')](BF4)2.5·H2O·0.5C2H5OH (2) (L2=2-(diphenylphosphino)benzylidene-2-(3, 6-bis(ethylamino)-2, 7-dimethyl-9H-xanthen-9-yl)benzothiohydrazide, L2'=2-(diphenylphosphinooxide)benzylidene-2-(3, 6-bis(ethylamino)-2, 7-dimethyl-9H-xanthen-9-yl) benzothiohydrazide) containing rhodamine groups exhibited activity in light driven hydrogen evolution with the TON and initial TOF reaching to 2 800 molH2·molcat-1 and 930 molH2·molcat-1·h-1, respectively, which is much higher than that of complex [Co(L1)(L1')](BF4)·0.5H2O (1) (L1=2-(diphenylphosphino)benzylidene hydrazinecarbodithionate, L1'=2-(diphenyl-phosphinooxide)benzylidene hydrazinecarbodithionate) under similar conditions. The higher catalytic activity was attributed to the potential intermolecular π-π stack interactions between the catalyst 2 and photosensitizer fluorescein (Fl) benefiting the photoinduced electron transfer between the photosensitizer and the photocatalyst.CCDC:1523357;1, 1523358, 2.
Two cobalt complexes containing NSP (nitrogen-sulphur-phosphor) chelator prepared from thiose-micarbazone ligands with different terminal functional groups and triphenylphosphine moiety have been synthesized in high yield and characterized. Their photocatalytic activity for hydrogen evolution under visible light irradiation was investigated. The photocatalyst [Co(L2)(L2')](BF4)2.5·H2O·0.5C2H5OH (2) (L2=2-(diphenylphosphino)benzylidene-2-(3, 6-bis(ethylamino)-2, 7-dimethyl-9H-xanthen-9-yl)benzothiohydrazide, L2'=2-(diphenylphosphinooxide)benzylidene-2-(3, 6-bis(ethylamino)-2, 7-dimethyl-9H-xanthen-9-yl) benzothiohydrazide) containing rhodamine groups exhibited activity in light driven hydrogen evolution with the TON and initial TOF reaching to 2 800 molH2·molcat-1 and 930 molH2·molcat-1·h-1, respectively, which is much higher than that of complex [Co(L1)(L1')](BF4)·0.5H2O (1) (L1=2-(diphenylphosphino)benzylidene hydrazinecarbodithionate, L1'=2-(diphenyl-phosphinooxide)benzylidene hydrazinecarbodithionate) under similar conditions. The higher catalytic activity was attributed to the potential intermolecular π-π stack interactions between the catalyst 2 and photosensitizer fluorescein (Fl) benefiting the photoinduced electron transfer between the photosensitizer and the photocatalyst.CCDC:1523357;1, 1523358, 2.
2017, 33(6): 939-946
doi: 10.11862/CJIC.2017.090
Abstract:
A series of pyrazolate-based dipalladium(Ⅱ, Ⅱ) complexes named [Pd2(bpy)2L2]2+ (1), [Pd2(dmbpy)2L2]2+ (2) and [[Pd2(phen)2L2]2+ (3) (bpy=2, 2'-bipyridine, dmbpy=4, 4'-dimethyl-2, 2'-bipyridine. phen=1, 10-phenanthroline) have been synthesized through a directed coordination approach that involves spontaneous deprotonation of the 1H-pyrazolyl ligands(HL) in aqueous solution driven by coordination effect. All of new complexes 1~3 have been fully characterized by 1H NMR, 13C NMR, ESI-MS and single-crystal X-ray diffraction analysis. A weak intramolecular Pd…Pd (0.303~0.313 nm) bonding interaction exist in the solid crystal structure, a 1D helical chain network formed by hydrogen bonds interactions between intermolecular, which can be employed as a new kind of high-efficiency catalysts for Suzuki-coupling reaction.CCDC: 1519041, 1·2PF6-; 1536149, 2·2PF6-; 1536150, 3·2PF6-.
A series of pyrazolate-based dipalladium(Ⅱ, Ⅱ) complexes named [Pd2(bpy)2L2]2+ (1), [Pd2(dmbpy)2L2]2+ (2) and [[Pd2(phen)2L2]2+ (3) (bpy=2, 2'-bipyridine, dmbpy=4, 4'-dimethyl-2, 2'-bipyridine. phen=1, 10-phenanthroline) have been synthesized through a directed coordination approach that involves spontaneous deprotonation of the 1H-pyrazolyl ligands(HL) in aqueous solution driven by coordination effect. All of new complexes 1~3 have been fully characterized by 1H NMR, 13C NMR, ESI-MS and single-crystal X-ray diffraction analysis. A weak intramolecular Pd…Pd (0.303~0.313 nm) bonding interaction exist in the solid crystal structure, a 1D helical chain network formed by hydrogen bonds interactions between intermolecular, which can be employed as a new kind of high-efficiency catalysts for Suzuki-coupling reaction.CCDC: 1519041, 1·2PF6-; 1536149, 2·2PF6-; 1536150, 3·2PF6-.
2017, 33(6): 1030-1034
doi: 10.11862/CJIC.2017.120
Abstract:
Double core-shells composite miscorsphere of PS/Au/Cu have been prepared by electrodepositing Cu on the PS-Au composite miscorsphere which is electrodeposited Au on the template of hollow polystyrene microsphere in the self-designed electrodepositing setup. Firstly, PS-Au miscorsphere keep a good spherical symmetric. And the Au electrodeposit is fine with thickness of 5.6 μm. Secondly, Cu is electrodeposited on integral PS-Au miscorsphere selected. Cu grow along crystal structure of Au because of the same face-centered cubic structure. Then the section of Au-Cu is compact. Finally, the thickness of Cu is 8.62 μm, the Au is 4.04 μm. The morphology, thickness, composition and roughness of PS/Au/Cu microsphere and double core-shells are studied by 3D-Video microscope, SEM, EDS and XRD. The results show that the complete shells of uniform deposit, good smoothness and low roughness of PS/Au/Cu microsphere and Au-Cu are synthesized on the surface of hollow polystyrene microsphere.
Double core-shells composite miscorsphere of PS/Au/Cu have been prepared by electrodepositing Cu on the PS-Au composite miscorsphere which is electrodeposited Au on the template of hollow polystyrene microsphere in the self-designed electrodepositing setup. Firstly, PS-Au miscorsphere keep a good spherical symmetric. And the Au electrodeposit is fine with thickness of 5.6 μm. Secondly, Cu is electrodeposited on integral PS-Au miscorsphere selected. Cu grow along crystal structure of Au because of the same face-centered cubic structure. Then the section of Au-Cu is compact. Finally, the thickness of Cu is 8.62 μm, the Au is 4.04 μm. The morphology, thickness, composition and roughness of PS/Au/Cu microsphere and double core-shells are studied by 3D-Video microscope, SEM, EDS and XRD. The results show that the complete shells of uniform deposit, good smoothness and low roughness of PS/Au/Cu microsphere and Au-Cu are synthesized on the surface of hollow polystyrene microsphere.
2017, 33(6): 1035-1042
doi: 10.11862/CJIC.2017.123
Abstract:
Three new mononuclear ruthenium complexes [Ru(bpy)2(paH)]PF6(1), [Ru(dmb)2(paH)]PF6(2) and [Ru(phen)2(paH)]PF6(3)(bpy=2, 2'-bipyridine, dmb=4, 4'-dimethyl-2, 2'-bipyridine, phen=phenanthroline, paH=pyridinecarboxylic acid) were synthesized and characterized using elemental analysis, infrared, nuclear magnetic spectroscopy and electrospray ionization mass spectrometry.Their photophysical and electrochemical properties were also studied. The complexes 1~3 undergo metal centered oxidation and the Ru(Ⅱ)/Ru(Ⅲ) redox couple peak are in 0.7~1.0 V versus a saturated calomel electrode. The cytotoxicity of these complexes in vitro was evaluated using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide(MTT) assay. The results indicated that 1~3 exhibited significant dose-dependent cytotoxicity to human breast cancer (MCF-7), gastric cancer (AGS) and lung cancer (A549) tumour cell lines. It is worth noting that 2 showed excellent antitumor effects in a cellular study (IC50 value of 2.85 μmol·L-1 for human breast cancer cells in vitro).
Three new mononuclear ruthenium complexes [Ru(bpy)2(paH)]PF6(1), [Ru(dmb)2(paH)]PF6(2) and [Ru(phen)2(paH)]PF6(3)(bpy=2, 2'-bipyridine, dmb=4, 4'-dimethyl-2, 2'-bipyridine, phen=phenanthroline, paH=pyridinecarboxylic acid) were synthesized and characterized using elemental analysis, infrared, nuclear magnetic spectroscopy and electrospray ionization mass spectrometry.Their photophysical and electrochemical properties were also studied. The complexes 1~3 undergo metal centered oxidation and the Ru(Ⅱ)/Ru(Ⅲ) redox couple peak are in 0.7~1.0 V versus a saturated calomel electrode. The cytotoxicity of these complexes in vitro was evaluated using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide(MTT) assay. The results indicated that 1~3 exhibited significant dose-dependent cytotoxicity to human breast cancer (MCF-7), gastric cancer (AGS) and lung cancer (A549) tumour cell lines. It is worth noting that 2 showed excellent antitumor effects in a cellular study (IC50 value of 2.85 μmol·L-1 for human breast cancer cells in vitro).
2017, 33(6): 1043-1050
doi: 10.11862/CJIC.2017.116
Abstract:
The title coordination polymers of {[M3(pyta)2(H2O)8]·4H2O}n(M=Co(1), Ni(2)) based on H3pyta (H3pyta=pyridine-2, 4, 6-tricarboxylic acid) had been synthesized under hydrothermal synthesis conditions with same temperature, molar ratio and solvent, but different metal salts. X-ray diffraction analysis shows that these two polymers are hetero-isomorphic and belong to the monoclinic system, P21/c space group. The magnetic investigation shows that polymers 1 and 2 exhibit a ferromagnetic coupling between M(Ⅱ) ions. CCDC: 1524314, 1; 1000880, 2.
The title coordination polymers of {[M3(pyta)2(H2O)8]·4H2O}n(M=Co(1), Ni(2)) based on H3pyta (H3pyta=pyridine-2, 4, 6-tricarboxylic acid) had been synthesized under hydrothermal synthesis conditions with same temperature, molar ratio and solvent, but different metal salts. X-ray diffraction analysis shows that these two polymers are hetero-isomorphic and belong to the monoclinic system, P21/c space group. The magnetic investigation shows that polymers 1 and 2 exhibit a ferromagnetic coupling between M(Ⅱ) ions. CCDC: 1524314, 1; 1000880, 2.
2017, 33(6): 1051-1058
doi: 10.11862/CJIC.2017.124
Abstract:
Two new M(Ⅱ)-Mn(Ⅲ) complexes {[Mn(Ⅲ)(salen)]4[Mn(Ⅲ)(salen)(H2O)]2[M(Ⅱ)(CN)6]}(ClO4)2·2H2O (M=Ru (1) and Os (2)) (salen2-=N, N'-ethylenebis(salicylideneaminato)dianion) have been synthesized based on [Mn(Ⅲ)(salen)]+ segment and hexacyanide-containing building blocks [M(Ⅱ)(CN)6]4-. Single crystal X-ray diffraction analyses show that both complexes are isostructurally two-dimensional (2D) structures in which cyanide-bridged heptanuclear [Mn(Ⅲ)6M(Ⅱ)]2+ units are linked together by double phenolate bridges. Magnetic studies show that they are abnormal antiferromagnetic through the double phenolate bridges with the magnetic coupling constant J=-0.340 cm-1 for 1 and -0.561 cm-1 for 2 based on the spin exchange Hamiltonian Ĥ=-2JMnMnŜMn1ŜMn2.
Two new M(Ⅱ)-Mn(Ⅲ) complexes {[Mn(Ⅲ)(salen)]4[Mn(Ⅲ)(salen)(H2O)]2[M(Ⅱ)(CN)6]}(ClO4)2·2H2O (M=Ru (1) and Os (2)) (salen2-=N, N'-ethylenebis(salicylideneaminato)dianion) have been synthesized based on [Mn(Ⅲ)(salen)]+ segment and hexacyanide-containing building blocks [M(Ⅱ)(CN)6]4-. Single crystal X-ray diffraction analyses show that both complexes are isostructurally two-dimensional (2D) structures in which cyanide-bridged heptanuclear [Mn(Ⅲ)6M(Ⅱ)]2+ units are linked together by double phenolate bridges. Magnetic studies show that they are abnormal antiferromagnetic through the double phenolate bridges with the magnetic coupling constant J=-0.340 cm-1 for 1 and -0.561 cm-1 for 2 based on the spin exchange Hamiltonian Ĥ=-2JMnMnŜMn1ŜMn2.
2017, 33(6): 1059-1064
doi: 10.11862/CJIC.2017.125
Abstract:
By using a tripodal ligand tris(3, 5-bimethyl-pyrazolylmethyl)amine (TMPzA) and a bridged ligand thiophenedicarboxylic acid (H2TPDC), two binuclear copper(Ⅱ) complexes have been synthesized and characterized. It has been found that TMPzA lost an arm and coordinated to copper with di(3, 5-bimethyl-pyrazolylmethyl)amine(DMPzA) in complex [Cu2(DMPzA)2(TPDC)2]ClO4 (1). The structure presented a microcycle with the Cu(1)…Cu(1A) distance of 0.786 84 nm. The complex [Cu2(TMPzA)2(TPDC)(H2O)2](ClO4)2 (2) is a binuclear structure and with the TMPzA completely. The investigation in Feton system shows that complex 1 has better hydroxyl radicals scavenging property than that of complex 2. CCDC: 1411232, 1; 1411233, 2.
By using a tripodal ligand tris(3, 5-bimethyl-pyrazolylmethyl)amine (TMPzA) and a bridged ligand thiophenedicarboxylic acid (H2TPDC), two binuclear copper(Ⅱ) complexes have been synthesized and characterized. It has been found that TMPzA lost an arm and coordinated to copper with di(3, 5-bimethyl-pyrazolylmethyl)amine(DMPzA) in complex [Cu2(DMPzA)2(TPDC)2]ClO4 (1). The structure presented a microcycle with the Cu(1)…Cu(1A) distance of 0.786 84 nm. The complex [Cu2(TMPzA)2(TPDC)(H2O)2](ClO4)2 (2) is a binuclear structure and with the TMPzA completely. The investigation in Feton system shows that complex 1 has better hydroxyl radicals scavenging property than that of complex 2. CCDC: 1411232, 1; 1411233, 2.
2017, 33(6): 1065-1073
doi: 10.11862/CJIC.2017.142
Abstract:
ZnO nanoparticles were synthesized by one step solid state reaction using only zinc sulfate heptahydrate and sodium hydroxide. The synthesized samples were characterized with various analysis methods including of X-ray diffraction (XRD), Fourier transform infrared absorption spectroscopy (FTIR), Thermogravimetric analysis (TG), Scanning electron microscope (SEM), Transmission electron microscopy (TEM), N2 adsorpation-desorpation, and Ultraviolet visible diffuse reflectance spectrum (UV-Vis DRS). The experimental results indicate that the dosage of NaOH is an important parameter in the process, which can affect the composition, crystallinity and morphology of the ZnO nanoparticles. Mean while, the formation scheme of ZnO nanoparticles includes that ZnSO4·7H2O and NaOH were grinded to be full contact, then ZnSO4·7H2O reacted with NaOH to form Zn4SO4(OH)6·5H2O. Subsequently, ZnO crystal nucleus would be generated and grown into a ZnO sheets by the sufficient heat of solution from NaOH. In the final, the photocatalytic property and kinetics were evaluated by the photodegradation of methyl orange. The ZnO nanoparticles exhibit excellent photocatalytic activity under ultraviolet light. The photodegradation of methyl orange by ZnO nanoparticles conforms to the pseudo first order kinetics.
ZnO nanoparticles were synthesized by one step solid state reaction using only zinc sulfate heptahydrate and sodium hydroxide. The synthesized samples were characterized with various analysis methods including of X-ray diffraction (XRD), Fourier transform infrared absorption spectroscopy (FTIR), Thermogravimetric analysis (TG), Scanning electron microscope (SEM), Transmission electron microscopy (TEM), N2 adsorpation-desorpation, and Ultraviolet visible diffuse reflectance spectrum (UV-Vis DRS). The experimental results indicate that the dosage of NaOH is an important parameter in the process, which can affect the composition, crystallinity and morphology of the ZnO nanoparticles. Mean while, the formation scheme of ZnO nanoparticles includes that ZnSO4·7H2O and NaOH were grinded to be full contact, then ZnSO4·7H2O reacted with NaOH to form Zn4SO4(OH)6·5H2O. Subsequently, ZnO crystal nucleus would be generated and grown into a ZnO sheets by the sufficient heat of solution from NaOH. In the final, the photocatalytic property and kinetics were evaluated by the photodegradation of methyl orange. The ZnO nanoparticles exhibit excellent photocatalytic activity under ultraviolet light. The photodegradation of methyl orange by ZnO nanoparticles conforms to the pseudo first order kinetics.
2017, 33(6): 1074-1080
doi: 10.11862/CJIC.2017.117
Abstract:
Cyclopentadienes C5HMe4Ar (Ar=Ph, 4-CH3Ph, 4-OCH3Ph, 4-ClPh, 4-BrPh) reacted with Re2(CO)10 in refluxing xylene to give new aryl-substituted tetramethylcyclopentadienyl mononuclear metal carbonyl complexes [(η5-C5Me4Ar)Re(CO)3] (Ar=Ph (1), 4-CH3Ph (2), 4-OCH3Ph (3), 4-ClPh (4), 4-BrPh (5)), respectively. The five new complexes were characterized by elemental analysis, IR, 1H NMR and 13C NMR spectroscopy. The crystal structures of complexes 1~5 were determined by X-ray crystal diffraction analysis. All five of these complexes have significant catalytic activity in Friedel-Crafts reactions of aromatic compounds with alkylation reagents. CCDC: 1463217, 1; 1506704, 2; 1484954, 3; 1484955, 4; 1506705, 5.
Cyclopentadienes C5HMe4Ar (Ar=Ph, 4-CH3Ph, 4-OCH3Ph, 4-ClPh, 4-BrPh) reacted with Re2(CO)10 in refluxing xylene to give new aryl-substituted tetramethylcyclopentadienyl mononuclear metal carbonyl complexes [(η5-C5Me4Ar)Re(CO)3] (Ar=Ph (1), 4-CH3Ph (2), 4-OCH3Ph (3), 4-ClPh (4), 4-BrPh (5)), respectively. The five new complexes were characterized by elemental analysis, IR, 1H NMR and 13C NMR spectroscopy. The crystal structures of complexes 1~5 were determined by X-ray crystal diffraction analysis. All five of these complexes have significant catalytic activity in Friedel-Crafts reactions of aromatic compounds with alkylation reagents. CCDC: 1463217, 1; 1506704, 2; 1484954, 3; 1484955, 4; 1506705, 5.
2017, 33(6): 1081-1089
doi: 10.11862/CJIC.2017.132
Abstract:
Pd/Fe3O4 NPs have been successfully synthesized using polyvinyl pyrrolidone as a stabilizing agent. The resultant samples were characterized by X-ray diffraction, transmission electron microscopy, inductively coupled plasma, and magnetic studies. The Pd/Fe3O4 NPs catalyst was also applied in the Heck reaction to evaluate the catalytic performance. The results show that the cubic phase of Pd coexists with the cubic phase of Fe3O4, and the catalysts have size less 20 nm and the excellent catalytic activity of Pd/Fe3O4 NPs in the Heck reaction. In addition, the catalyst can be recovered via a magnet and reused several times without significant loss of its catalytic activity.
Pd/Fe3O4 NPs have been successfully synthesized using polyvinyl pyrrolidone as a stabilizing agent. The resultant samples were characterized by X-ray diffraction, transmission electron microscopy, inductively coupled plasma, and magnetic studies. The Pd/Fe3O4 NPs catalyst was also applied in the Heck reaction to evaluate the catalytic performance. The results show that the cubic phase of Pd coexists with the cubic phase of Fe3O4, and the catalysts have size less 20 nm and the excellent catalytic activity of Pd/Fe3O4 NPs in the Heck reaction. In addition, the catalyst can be recovered via a magnet and reused several times without significant loss of its catalytic activity.
2017, 33(6): 1090-1096
doi: 10.11862/CJIC.2017.128
Abstract:
Reaction of CdCl2 or ZnCl2·4H2O, 5-hydroxyisophthalic acid (5-OHH2IP) as well as 1, 5-bis(2-ethyl-imidazolyl)pentane(BEIP) results in formation of a 1D [Cd(BEIP)(Cl)2]n (1) and 2D [Zn(BEIP)(5-OHIP)]n (2). X-ray diffraction crystal structure analysis shows that 1 crystallizes in orthorhombic system, space group Pca21, while 2 is of monoclinic, space group P21/n with β=100.542(4)°. In 1, the 1, 5-bis(2-ethyl-imidazolyl)pentane links all the Cd atoms into a 1D chain. In 2, the carboxylate group with μ2-η1:η1 coordination mode links metal atoms to give a 1D zigzag chain structure, which forming the 2D layer through Zn-N interactions by BEIP ligands. Finally the 2D layers are further assembled into 3D framework by the H-bond interaction. In addition, the properties of complexes 1 and 2 have been investigated, which exhibit good fluorescence in the solid state at room temperature. And complex 2 shows good photocatalytic activity for the degradation of methyl orange solution. CCDC:1523229, 1; 1523230, 2.
Reaction of CdCl2 or ZnCl2·4H2O, 5-hydroxyisophthalic acid (5-OHH2IP) as well as 1, 5-bis(2-ethyl-imidazolyl)pentane(BEIP) results in formation of a 1D [Cd(BEIP)(Cl)2]n (1) and 2D [Zn(BEIP)(5-OHIP)]n (2). X-ray diffraction crystal structure analysis shows that 1 crystallizes in orthorhombic system, space group Pca21, while 2 is of monoclinic, space group P21/n with β=100.542(4)°. In 1, the 1, 5-bis(2-ethyl-imidazolyl)pentane links all the Cd atoms into a 1D chain. In 2, the carboxylate group with μ2-η1:η1 coordination mode links metal atoms to give a 1D zigzag chain structure, which forming the 2D layer through Zn-N interactions by BEIP ligands. Finally the 2D layers are further assembled into 3D framework by the H-bond interaction. In addition, the properties of complexes 1 and 2 have been investigated, which exhibit good fluorescence in the solid state at room temperature. And complex 2 shows good photocatalytic activity for the degradation of methyl orange solution. CCDC:1523229, 1; 1523230, 2.
2017, 33(6): 923-931
doi: 10.11862/CJIC.2017.091
Abstract:
The electronic structures and magnetic properties of Fe3O4, Fe3O4(001) surface and transition elements -doped (001) surfaces were calculated based on the density functional theories. The results show that the half-metallicity of Fe3O4 is from Fe-ions on B-sites, and magnetic moment is from spin polarization of 3d-orbits.For the Fe3O4(001) surface, the A-layer termination is more stabilized with half-metal character. Fe-ions on A-sites of A-layer termination are substituted by doped V-ions, Cr-ions, Mn-ions, Co-ions, Cu-ions and Zn-ions so that the new surface structures are designed. All of them have half-metal character, and the Mn-doped surface is the most stabilized with greater magnetic moment.
The electronic structures and magnetic properties of Fe3O4, Fe3O4(001) surface and transition elements -doped (001) surfaces were calculated based on the density functional theories. The results show that the half-metallicity of Fe3O4 is from Fe-ions on B-sites, and magnetic moment is from spin polarization of 3d-orbits.For the Fe3O4(001) surface, the A-layer termination is more stabilized with half-metal character. Fe-ions on A-sites of A-layer termination are substituted by doped V-ions, Cr-ions, Mn-ions, Co-ions, Cu-ions and Zn-ions so that the new surface structures are designed. All of them have half-metal character, and the Mn-doped surface is the most stabilized with greater magnetic moment.
2017, 33(6): 932-938
doi: 10.11862/CJIC.2017.133
Abstract:
Lattice parameters and crystal structures of two metal-organic perovskites[C(NH2)3] [Mn(HCOO)3] (1) and [(CH2)3NH2] [Mn(HCOO)3] (2) are investigated via variable-temperature single-crystal (VT-SCRD) X-ray diffraction and transmission electron microscopy (TEM) experiments. The significant negative thermal expansion (NTE) phenomena along their c-axes are revealed. The average NTE coefficients of frameworks 1 and 2 are αc1=-1.2(1)×10-5 K-1 and αc2=-6.1(11)×10-5 K-1, respectively, obtained via linear fits using the Pascal software. A hinge-strut like structure model is used to explain the NTE mechanism of these two frameworks, the perovskite frameworks 1 and 2 can be considered as a simple hinge-strut like structure which is a prototypic motif for anisotropic thermal expansion, the formate ligand and Mn(Ⅱ) stand for the hinge and strut, respectively, the hinge angles are represented as θ and φ. The results indicate that the hydrogen bond lengths and angles between the anion framework and the A-site amine cations change slightly with increasing temperature, which induce the distortion of the perovskite frameworks and give rise to the increase of the hinge angle θ but decrease of φ with increasing temperature. These structural rearrangements result in the NTE along the diagonal of the pseudocubic perovskite framework. Furthermore, the two frameworks show significantly different thermal expansion properties due to their distinct modes of hydrogen-bonding between the framework hosts and A-site amine cations. In framework 2, each[(CH2)3NH2]+ is aligned with the ac plane and bonded to the two opposite edges within the same face of the pseudocubic unit cell by four hydrogen bonds. However in framework 1, each[C(NH2)3]+ is cross-linked to two perpendicular edges from two opposite faces of each pseudocubic unit cell by six hydrogen bonds and tilted with respect to the ac plane, which consequently gives more cross-linking constraints to the cubic unit cell along three orthogonal orientations. As a result of the constraint, the amine cation and anionic framework of 1 are bonded more tightly. Therefore, it is concluded that the number and orientation of hydrogen bonds have a marked impact on the thermal expansion properties of these two frameworks.
Lattice parameters and crystal structures of two metal-organic perovskites[C(NH2)3] [Mn(HCOO)3] (1) and [(CH2)3NH2] [Mn(HCOO)3] (2) are investigated via variable-temperature single-crystal (VT-SCRD) X-ray diffraction and transmission electron microscopy (TEM) experiments. The significant negative thermal expansion (NTE) phenomena along their c-axes are revealed. The average NTE coefficients of frameworks 1 and 2 are αc1=-1.2(1)×10-5 K-1 and αc2=-6.1(11)×10-5 K-1, respectively, obtained via linear fits using the Pascal software. A hinge-strut like structure model is used to explain the NTE mechanism of these two frameworks, the perovskite frameworks 1 and 2 can be considered as a simple hinge-strut like structure which is a prototypic motif for anisotropic thermal expansion, the formate ligand and Mn(Ⅱ) stand for the hinge and strut, respectively, the hinge angles are represented as θ and φ. The results indicate that the hydrogen bond lengths and angles between the anion framework and the A-site amine cations change slightly with increasing temperature, which induce the distortion of the perovskite frameworks and give rise to the increase of the hinge angle θ but decrease of φ with increasing temperature. These structural rearrangements result in the NTE along the diagonal of the pseudocubic perovskite framework. Furthermore, the two frameworks show significantly different thermal expansion properties due to their distinct modes of hydrogen-bonding between the framework hosts and A-site amine cations. In framework 2, each[(CH2)3NH2]+ is aligned with the ac plane and bonded to the two opposite edges within the same face of the pseudocubic unit cell by four hydrogen bonds. However in framework 1, each[C(NH2)3]+ is cross-linked to two perpendicular edges from two opposite faces of each pseudocubic unit cell by six hydrogen bonds and tilted with respect to the ac plane, which consequently gives more cross-linking constraints to the cubic unit cell along three orthogonal orientations. As a result of the constraint, the amine cation and anionic framework of 1 are bonded more tightly. Therefore, it is concluded that the number and orientation of hydrogen bonds have a marked impact on the thermal expansion properties of these two frameworks.
2017, 33(6): 947-953
doi: 10.11862/CJIC.2017.092
Abstract:
Mesoporous bioactive glass microtubes were successfully prepared through a surface sol-gel process followed by a calcination treatment and using filter paper as the biotemplate. The tubular structures of rapid filter paper were replicated with the walls containing highly ordered mesoporous bioactive glasses as well. This simple biotemplate method provided a cost-effective and eco-friendly route to obtain advanced self-assembling mesoporous bioactive glass microtubes. By introducing FeCl3, mesoporous bioactive glass microtubes had not only delicate multichannel tubular structures, but also magnetic properties. As-synthesized mesoporous bioactive glass microtubes were characterized by scanning electron microscope (SEM), powder X-ray diffraction (XRD), transmission electron microscope (TEM) and nitrogen adsorption/desorption, fourier transform IR (FTIR) spectroscopy, and magnetization curves. The in vitro mineralization ability of mesoporous bioactive glass microtubes was tested in SBF to monitor the formation of hydroxycarbonate apatite (HCA). Dexamethasone (DEX) was employed as a model drug and the release profiles showed that the porous materials had a sustained drug delivery capability. The one-dimensional hollow tubular structure of the materials allowed the shorter release time of the DEX. The materials of three-day release time could also be used as carriers for oral drug. The biocompatibilities were also evaluated by culturing the MC3T3-E1 cells on mesoporous bioactive glass microtubes. The results showed that the materials had excellent potential applications in the field of sustained drug delivery.
Mesoporous bioactive glass microtubes were successfully prepared through a surface sol-gel process followed by a calcination treatment and using filter paper as the biotemplate. The tubular structures of rapid filter paper were replicated with the walls containing highly ordered mesoporous bioactive glasses as well. This simple biotemplate method provided a cost-effective and eco-friendly route to obtain advanced self-assembling mesoporous bioactive glass microtubes. By introducing FeCl3, mesoporous bioactive glass microtubes had not only delicate multichannel tubular structures, but also magnetic properties. As-synthesized mesoporous bioactive glass microtubes were characterized by scanning electron microscope (SEM), powder X-ray diffraction (XRD), transmission electron microscope (TEM) and nitrogen adsorption/desorption, fourier transform IR (FTIR) spectroscopy, and magnetization curves. The in vitro mineralization ability of mesoporous bioactive glass microtubes was tested in SBF to monitor the formation of hydroxycarbonate apatite (HCA). Dexamethasone (DEX) was employed as a model drug and the release profiles showed that the porous materials had a sustained drug delivery capability. The one-dimensional hollow tubular structure of the materials allowed the shorter release time of the DEX. The materials of three-day release time could also be used as carriers for oral drug. The biocompatibilities were also evaluated by culturing the MC3T3-E1 cells on mesoporous bioactive glass microtubes. The results showed that the materials had excellent potential applications in the field of sustained drug delivery.
2017, 33(6): 954-962
doi: 10.11862/CJIC.2017.093
Abstract:
Br- ions doped Bi2WO6 was prepared using bismuth nitrate Bi(NO3)3·5H2O and sodium tungstate Na2WO4·2H2O as raw materials by hydrothermal synthesis method. The effect of Br- doping on the phase structure, morphology and visible light catalytic properties of Bi2WO6 was investigated using XRD, SEM, TEM, XPS, Raman, PL and DRS. The results indicated that the visible-light-driven photocatalytic performance of Bi2WO6 was greatly enhanced after Br- doping. When Br- was doped with 8% of the amount (percentage of amount of substance), the Bi2WO6 photocatalyst displayed the best photocatalytic performance. It could decompose 96.73% RhB after 40 minutes irradiation, which was 36.32% higher than that of the pristine one.
Br- ions doped Bi2WO6 was prepared using bismuth nitrate Bi(NO3)3·5H2O and sodium tungstate Na2WO4·2H2O as raw materials by hydrothermal synthesis method. The effect of Br- doping on the phase structure, morphology and visible light catalytic properties of Bi2WO6 was investigated using XRD, SEM, TEM, XPS, Raman, PL and DRS. The results indicated that the visible-light-driven photocatalytic performance of Bi2WO6 was greatly enhanced after Br- doping. When Br- was doped with 8% of the amount (percentage of amount of substance), the Bi2WO6 photocatalyst displayed the best photocatalytic performance. It could decompose 96.73% RhB after 40 minutes irradiation, which was 36.32% higher than that of the pristine one.
2017, 33(6): 963-969
doi: 10.11862/CJIC.2017.114
Abstract:
A Li-rich Mn-based Li1.5Ni0.25Mn0.75O2.5 cathode material with excellent electrochemical performance is prepared using a combination of hydroxide co-precipitation and molten salt method. Powder X-ray diffraction (XRD), scanning electron microscopy (SEM), inductively coupled plasma-atomic emission spectrometer (ICP-AES), X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectroscopy (EIS) and galvanostatic charge-discharge tests are employed to analyze the particle morphology, crystal structure, and electrochemical properties of the as-prepared material. XRD results indicate that this sample has a more ordered α-NaFeO2 structure (space group R3m), and reduced Li+/Ni2+ cation mixing. Electrochemical results confirm that this sample has a dramatically decreased initial irreversible capacity loss, and excellent rate performance and cycling stability. Specifically, it delivers a small initial irreversible capacity loss of 50 mAh·g-1 (the first coulombic efficiency is 84%) between 2.0 and 4.8 V at 0.1C. At 10C rate, it can still exhibit a high discharge capacity of 102 mAh·g-1. After 100 cycles at 0.5C, the cathode also shows a discharge capacity of 205 mAh·g-1 with capacity retention of 90%.
A Li-rich Mn-based Li1.5Ni0.25Mn0.75O2.5 cathode material with excellent electrochemical performance is prepared using a combination of hydroxide co-precipitation and molten salt method. Powder X-ray diffraction (XRD), scanning electron microscopy (SEM), inductively coupled plasma-atomic emission spectrometer (ICP-AES), X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectroscopy (EIS) and galvanostatic charge-discharge tests are employed to analyze the particle morphology, crystal structure, and electrochemical properties of the as-prepared material. XRD results indicate that this sample has a more ordered α-NaFeO2 structure (space group R3m), and reduced Li+/Ni2+ cation mixing. Electrochemical results confirm that this sample has a dramatically decreased initial irreversible capacity loss, and excellent rate performance and cycling stability. Specifically, it delivers a small initial irreversible capacity loss of 50 mAh·g-1 (the first coulombic efficiency is 84%) between 2.0 and 4.8 V at 0.1C. At 10C rate, it can still exhibit a high discharge capacity of 102 mAh·g-1. After 100 cycles at 0.5C, the cathode also shows a discharge capacity of 205 mAh·g-1 with capacity retention of 90%.
2017, 33(6): 970-976
doi: 10.11862/CJIC.2017.113
Abstract:
Visible light-active boron doped TiO2 nanotube arrays (B/TNTs) were synthesized by adding NaBF4 in anodic oxidation electrolyte. The photocatalytic properties to methylene blue(MB) solution were investigated under visible light irradiation. FE-SEM analysis showed that the morphology of B/TNTs was obviously different. EDS, XPS and FTIR analysis indicated that boron was incorporated into the TNTs lattice to form B-O-Ti bond. B doping could effectively promote the formation of active group Ti-OH on the surface of TiO2, decrease the band gap energy and make the absorption edges of the samples red-shifting. Such effect became stronger with the increase of the B doping concentration. XRD analysis indicated that B doping promoted the growth of anatase grains. The doped TiO2 nanotubes can form anatase phase as pure one when calcined at 550 ℃. The B/TNTs with an optimal photocatalytic activity were fabricated with the NaBF4 concentration of 0.6%(w/w). The photocatalytic degradation rate of MB in 4 h increased from 39.90% for TNTs without NaBF4 addition to 69% for B/TNTs, and their photocatalytic degradation ability is basically unchanged after using 10 times. The total organic carbon(TOC) removal rates indicated that the MB can be efficiently mineralized under visible light illumination.
Visible light-active boron doped TiO2 nanotube arrays (B/TNTs) were synthesized by adding NaBF4 in anodic oxidation electrolyte. The photocatalytic properties to methylene blue(MB) solution were investigated under visible light irradiation. FE-SEM analysis showed that the morphology of B/TNTs was obviously different. EDS, XPS and FTIR analysis indicated that boron was incorporated into the TNTs lattice to form B-O-Ti bond. B doping could effectively promote the formation of active group Ti-OH on the surface of TiO2, decrease the band gap energy and make the absorption edges of the samples red-shifting. Such effect became stronger with the increase of the B doping concentration. XRD analysis indicated that B doping promoted the growth of anatase grains. The doped TiO2 nanotubes can form anatase phase as pure one when calcined at 550 ℃. The B/TNTs with an optimal photocatalytic activity were fabricated with the NaBF4 concentration of 0.6%(w/w). The photocatalytic degradation rate of MB in 4 h increased from 39.90% for TNTs without NaBF4 addition to 69% for B/TNTs, and their photocatalytic degradation ability is basically unchanged after using 10 times. The total organic carbon(TOC) removal rates indicated that the MB can be efficiently mineralized under visible light illumination.
2017, 33(6): 977-984
doi: 10.11862/CJIC.2017.130
Abstract:
Three-dimensionally ordered macroporous SiO2 (3DOM SiO2) with pore size of 250 nm was fabricated using the polystyrene colloidal crystal as template. The poly (glycidyl methacrylate) (PGMA) chains were grafted from the pore wall of 3DOM SiO2 by surface-initiated atom transfer radical polymerization technique (SI-ATRP). SEM micrographs indicated that the hybrid 3DOM materials were arranged in highly ordered fashion. TGA and GPC results revealed the grafted amount/molecular weight could be controlled by simply changing the SI-ATRP reaction time. Moreover, epoxy groups which introduced onto the pore wall of 3DOM SiO2 were carried out ring-opening reaction by nucleophile reagent. Subsequently, the epoxy groups were opened via further reactions. 3DOM hybrid SiO2 with different functional groups were prepared, which were confirmed by FT-IR. Furthermore, the 3DOM hybrid SiO2 functionalized with different functional groups were used as a adsorbent to removal salicylic acid from water. 3DOM SiO2-g-PGMA-DETA gained by ring-opening reaction of diethylenetriamine presented high adsorption capacity.
Three-dimensionally ordered macroporous SiO2 (3DOM SiO2) with pore size of 250 nm was fabricated using the polystyrene colloidal crystal as template. The poly (glycidyl methacrylate) (PGMA) chains were grafted from the pore wall of 3DOM SiO2 by surface-initiated atom transfer radical polymerization technique (SI-ATRP). SEM micrographs indicated that the hybrid 3DOM materials were arranged in highly ordered fashion. TGA and GPC results revealed the grafted amount/molecular weight could be controlled by simply changing the SI-ATRP reaction time. Moreover, epoxy groups which introduced onto the pore wall of 3DOM SiO2 were carried out ring-opening reaction by nucleophile reagent. Subsequently, the epoxy groups were opened via further reactions. 3DOM hybrid SiO2 with different functional groups were prepared, which were confirmed by FT-IR. Furthermore, the 3DOM hybrid SiO2 functionalized with different functional groups were used as a adsorbent to removal salicylic acid from water. 3DOM SiO2-g-PGMA-DETA gained by ring-opening reaction of diethylenetriamine presented high adsorption capacity.
2017, 33(6): 985-992
doi: 10.11862/CJIC.2017.115
Abstract:
CoAl2O4/ceramic honeycomb catalyst was prepared by coated method and was characterized by X-ray diffraction, N2 adsorption-desorption and transmission electron microscope. Catalytic ozonation of hydroquinone was conducted to evaluate its catalytic activity. The results showed that the crystal phase of CoAl2O4/ceramic honeycomb belonged to a typical spinel structure with a large specific surface area of 77 m2·g-1, pore volume of 0.001 7 cm3·g-1 and pore size of 3.9 nm. The removal efficiencies of hydroquinone and COD during ozonation of O3-CoAl2O4/ceramic honeycomb were 81.2% and 47.7%, respectively. The degradation efficiency of hydroquinone decreased significantly after the addition of tert-butanol, and the ozonation of CoAl2O4/ceramic honeycomb catalyst should follow a hydroxyl radical mechanism.
CoAl2O4/ceramic honeycomb catalyst was prepared by coated method and was characterized by X-ray diffraction, N2 adsorption-desorption and transmission electron microscope. Catalytic ozonation of hydroquinone was conducted to evaluate its catalytic activity. The results showed that the crystal phase of CoAl2O4/ceramic honeycomb belonged to a typical spinel structure with a large specific surface area of 77 m2·g-1, pore volume of 0.001 7 cm3·g-1 and pore size of 3.9 nm. The removal efficiencies of hydroquinone and COD during ozonation of O3-CoAl2O4/ceramic honeycomb were 81.2% and 47.7%, respectively. The degradation efficiency of hydroquinone decreased significantly after the addition of tert-butanol, and the ozonation of CoAl2O4/ceramic honeycomb catalyst should follow a hydroxyl radical mechanism.
2017, 33(6): 993-999
doi: 10.11862/CJIC.2017.119
Abstract:
Pt/g-C3N4/KB was prepared by a facile method, Pt nanoparticles were prepared through solution plasma process, g-C3N4 was exfoliated by thermal oxidation to obtain g-C3N4 nanosheets (g-C3N4 NS), and g-C3N4 NS was treated further by hydrothermal method. The obtained Pt/g-C3N4/KB was characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The activity of samples for methanol electrocatalytic oxidation reaction was evaluated by cyclic voltammetry, respectively. The Pt/g-C3N4/KB exhibits much better activity than that of Pt/KB. The improvement may be attributed the excellent chemical stability of g-C3N4, high activity of Pt atoms owing to the N element of g-C3N4, and methanol molecule may be adsorbed to g-C3N4 owing to the hydrogen bond.
Pt/g-C3N4/KB was prepared by a facile method, Pt nanoparticles were prepared through solution plasma process, g-C3N4 was exfoliated by thermal oxidation to obtain g-C3N4 nanosheets (g-C3N4 NS), and g-C3N4 NS was treated further by hydrothermal method. The obtained Pt/g-C3N4/KB was characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The activity of samples for methanol electrocatalytic oxidation reaction was evaluated by cyclic voltammetry, respectively. The Pt/g-C3N4/KB exhibits much better activity than that of Pt/KB. The improvement may be attributed the excellent chemical stability of g-C3N4, high activity of Pt atoms owing to the N element of g-C3N4, and methanol molecule may be adsorbed to g-C3N4 owing to the hydrogen bond.
2017, 33(6): 1000-1006
doi: 10.11862/CJIC.2017.129
Abstract:
LiMnPO4 was synthesized by solvothermal method. LiMnPO4/carbon/graphene composites with different amount of pyrolytic carbon and graphene were prepared using sucrose and graphene as carbon sources. The effect of pyrolytic carbon and graphene on the performance of material was investigated. The morphology of the material was characterized by scanning electron microscope (SEM) and transmission electron microscope (TEM). Pyrolytic carbon coating can enhance the surface electronic conductivity of LiMnPO4 nanoplates, which plays a major role in improving the performances of the material. Graphene can enhance the electronic and ionic conductivity between nanoplates, and then improve the electrochemical properties of the material. Electrochemical measurements indicate that LiMnPO4 electrode with 4% pyrolytic carbon and 2% graphene exhibits better electrochemical performances. The specific capacity is 139.1 mAh·g-1 at 0.5C and the capacity retention is 93.6% after 100 cycles. Compared with single carbon and single graphene LiMnPO4 electrode, the specific capacity at 0.5C of LMP-C(4)-G(2) electrode is increased by 35.0% and 48.6%.
LiMnPO4 was synthesized by solvothermal method. LiMnPO4/carbon/graphene composites with different amount of pyrolytic carbon and graphene were prepared using sucrose and graphene as carbon sources. The effect of pyrolytic carbon and graphene on the performance of material was investigated. The morphology of the material was characterized by scanning electron microscope (SEM) and transmission electron microscope (TEM). Pyrolytic carbon coating can enhance the surface electronic conductivity of LiMnPO4 nanoplates, which plays a major role in improving the performances of the material. Graphene can enhance the electronic and ionic conductivity between nanoplates, and then improve the electrochemical properties of the material. Electrochemical measurements indicate that LiMnPO4 electrode with 4% pyrolytic carbon and 2% graphene exhibits better electrochemical performances. The specific capacity is 139.1 mAh·g-1 at 0.5C and the capacity retention is 93.6% after 100 cycles. Compared with single carbon and single graphene LiMnPO4 electrode, the specific capacity at 0.5C of LMP-C(4)-G(2) electrode is increased by 35.0% and 48.6%.
2017, 33(6): 1007-1014
doi: 10.11862/CJIC.2017.110
Abstract:
Two Cu(Ⅰ)/Cu(Ⅱ) complexes, formulated as [Cu2(TTB)0.5(PPh3)]n(1) and {[Cu(TTB)0.5(H2O)2]·H2O}n(2) (H4TTB=1, 2, 4, 5-tetra-(2H-tetrazole-5-yl)-benzene, PPh3=triphenyl phosphine) have been obtained by solvothermal/hydrothermal reactions for the exploration of efficient photocatalytic degradation of organic dye pollutants. The two complexes were characterized by IR, TG, PXRD and X-ray single crystal determination. Complex 1 exhibits a novel 2D structure with 12 coordination atoms in a TTB4-, and complex 2 features an irregular 1D double chain structure. Moreover, under visible light, both complexes 1 and 2 display higher activation for the photocatalytic decomposition of rhodamine B (RhB) and methylene blue (MB). The degradation efficiency can reach 88% (RhB) and 93% (MB) for 1, and 78% (RhB) and 93% (MB) for 2. Clearly, the photocatalytic degradation efficiency of complex 1 is similar to that of complex 2.
Two Cu(Ⅰ)/Cu(Ⅱ) complexes, formulated as [Cu2(TTB)0.5(PPh3)]n(1) and {[Cu(TTB)0.5(H2O)2]·H2O}n(2) (H4TTB=1, 2, 4, 5-tetra-(2H-tetrazole-5-yl)-benzene, PPh3=triphenyl phosphine) have been obtained by solvothermal/hydrothermal reactions for the exploration of efficient photocatalytic degradation of organic dye pollutants. The two complexes were characterized by IR, TG, PXRD and X-ray single crystal determination. Complex 1 exhibits a novel 2D structure with 12 coordination atoms in a TTB4-, and complex 2 features an irregular 1D double chain structure. Moreover, under visible light, both complexes 1 and 2 display higher activation for the photocatalytic decomposition of rhodamine B (RhB) and methylene blue (MB). The degradation efficiency can reach 88% (RhB) and 93% (MB) for 1, and 78% (RhB) and 93% (MB) for 2. Clearly, the photocatalytic degradation efficiency of complex 1 is similar to that of complex 2.
2017, 33(6): 1015-1022
doi: 10.11862/CJIC.2017.121
Abstract:
Using Ti and Ta powders as raw materials, carbon black as the reactive template, the nanosized carbide coating of TaTiC2 were grown in situ on the surface of carbon black by molten salt reaction. And using the as-prepared TaTiC2/C composites as the carbide precursors, the hollow Ta2O5/TiO2 composite photocatalysts were prepared by the controllable oxidation. The morphology, microstructure and pore structure of as-synthesized photocatalyst were characterized by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, UV-Vis diffuse reflectance spectroscopy (DRS) and N2 physical adsorption measurements. With methylene blue as the aimed degradation pollutant and mercury lamp as light source, The photocatalytic activities of hollow Ta2O5/TiO2 composite photocatalysts were evaluated by the photocatalytic degradation of methylene blue solution. Results indicated that the carbide coatings synthesized by molten salt reaction have uniform thickness (20~30 nm). TaTiC2 was the main crystalline phase of carbide and had nanosized particle size. The hollow Ta2O5/TiO2 composite photocatalysts have hollow macroporous structure of about 200 nm and mesoporous structure of about 10 nm in the shell. The existence of hollow macropores and mesopores can improve the adsorption of as-prepared photocatalysts for methylene blue. In addition, the coupling of electronic energy band structures of TiO2 and Ta2O5 can enhance the separation efficiency of photogenerated electrons and holes remarkably. Furthermore, the photocatalytic activity was improved observably. When the nTi:nTa is 2.5:1.5, the corresponding hollow Ta2O5/TiO2 composite photocatalyst exhibits the highest photocatalytic activity, and the ultraviolet light photocatalytic degradation rate for methylene blue is up to 97%.
Using Ti and Ta powders as raw materials, carbon black as the reactive template, the nanosized carbide coating of TaTiC2 were grown in situ on the surface of carbon black by molten salt reaction. And using the as-prepared TaTiC2/C composites as the carbide precursors, the hollow Ta2O5/TiO2 composite photocatalysts were prepared by the controllable oxidation. The morphology, microstructure and pore structure of as-synthesized photocatalyst were characterized by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, UV-Vis diffuse reflectance spectroscopy (DRS) and N2 physical adsorption measurements. With methylene blue as the aimed degradation pollutant and mercury lamp as light source, The photocatalytic activities of hollow Ta2O5/TiO2 composite photocatalysts were evaluated by the photocatalytic degradation of methylene blue solution. Results indicated that the carbide coatings synthesized by molten salt reaction have uniform thickness (20~30 nm). TaTiC2 was the main crystalline phase of carbide and had nanosized particle size. The hollow Ta2O5/TiO2 composite photocatalysts have hollow macroporous structure of about 200 nm and mesoporous structure of about 10 nm in the shell. The existence of hollow macropores and mesopores can improve the adsorption of as-prepared photocatalysts for methylene blue. In addition, the coupling of electronic energy band structures of TiO2 and Ta2O5 can enhance the separation efficiency of photogenerated electrons and holes remarkably. Furthermore, the photocatalytic activity was improved observably. When the nTi:nTa is 2.5:1.5, the corresponding hollow Ta2O5/TiO2 composite photocatalyst exhibits the highest photocatalytic activity, and the ultraviolet light photocatalytic degradation rate for methylene blue is up to 97%.
2017, 33(6): 1023-1029
doi: 10.11862/CJIC.2017.122
Abstract:
A tridentate Schiff base ligand (H2Brsth), derived from the condensation of 5-bromosalicylaldehyde and 2-acetylthiophene, hydrothermally reacted with Cu(Ⅱ) acetate in mixed-solvent of ethanol and water to yield tetranuclear complexes [Cu4(H2O)2(μ-Brsth)2(μ3-Brsth)2] (1) and [Cu4(H2O)2(Brsth)2(μ-Brsth)2(μ2-4, 4'-bipy)2] (2), which were characterized by elemental analyses, IR, electronic spectra, thermogravimetric analysis and single crystal X-ray diffraction. The X-ray diffraction analyses reveal that 1 crystallizes in the monoclinic space group P21/c with Z=2 while 2 in monoclinic space group C2/c with Z=4. In 1 and 2 each Cu(Ⅱ) atoms are five-coordinated with both distorted square pyramidal geometries. In 1 four Cu(Ⅱ) atoms are held together by four μ-O and/or μ3-O type phenoxo oxygen atoms from four individual Schiff base ligands to form a chair-shaped {Cu4O4} unit. In 2 two pairs of Cu(Ⅱ) atoms join two μ2-4, 4'-bipy molecules and two μ-phenoxo oxygen atoms from two Schiff base, respectively, to form a cyclic tetranuclear structure. The in vitro antitumor activities of ligand and complexes were tested by MTT method, which results show that the complexes have strong in vitro antitumor activity against HEPG2 cancer cells lines.CCDC: 1058056, 1; 1048382, 2.
A tridentate Schiff base ligand (H2Brsth), derived from the condensation of 5-bromosalicylaldehyde and 2-acetylthiophene, hydrothermally reacted with Cu(Ⅱ) acetate in mixed-solvent of ethanol and water to yield tetranuclear complexes [Cu4(H2O)2(μ-Brsth)2(μ3-Brsth)2] (1) and [Cu4(H2O)2(Brsth)2(μ-Brsth)2(μ2-4, 4'-bipy)2] (2), which were characterized by elemental analyses, IR, electronic spectra, thermogravimetric analysis and single crystal X-ray diffraction. The X-ray diffraction analyses reveal that 1 crystallizes in the monoclinic space group P21/c with Z=2 while 2 in monoclinic space group C2/c with Z=4. In 1 and 2 each Cu(Ⅱ) atoms are five-coordinated with both distorted square pyramidal geometries. In 1 four Cu(Ⅱ) atoms are held together by four μ-O and/or μ3-O type phenoxo oxygen atoms from four individual Schiff base ligands to form a chair-shaped {Cu4O4} unit. In 2 two pairs of Cu(Ⅱ) atoms join two μ2-4, 4'-bipy molecules and two μ-phenoxo oxygen atoms from two Schiff base, respectively, to form a cyclic tetranuclear structure. The in vitro antitumor activities of ligand and complexes were tested by MTT method, which results show that the complexes have strong in vitro antitumor activity against HEPG2 cancer cells lines.CCDC: 1058056, 1; 1048382, 2.
