Login In
2018 Volume 34 Issue 2
2018, 34(2): 217-229
doi: 10.11862/CJIC.2018.021
Abstract:
A new calix[4]arene-based ruthenium(Ⅱ) complex of[Ru2(bpy)4(H2L)](ClO4)4 (1) (bpy=2, 2'-bipyridine and H2L=11, 23-bis(2-imidazo[4, 5-f]-1, 10-phenanthroline)-25, 27-dihydroxy-26, 28-diethoxycarbonylpropyl-5, 17-di-p-t-butyl-calix[4]arene) was synthesized and characterized using an assortment of spectroscopic techniques such as IR, 1H NMR, 13C NMR, ESI-MS, and elementary analysis. The pH luminescence switching property of 1 was studied by means of spectrofluorimetric titrations in CH3CN/Britton-Robinson buffer solution (1: 100, V/V). The complex exhibited two-step separate protonation/deprotonation processes, and acting as a pH-induced "off-on-off" luminescence switch (Ion/Ioff=1.42 and 96.0). The anion sensing properties of complex 1 were thoroughly investigated in solution using absorption, emission, and 1H NMR spectral studies, which revealed that 1 acted as an efficient "turn off" emission sensor for F- and OAc-. Importantly, cellular imaging and cytotoxicity experiments demonstrated that 1 rapidly penetrate through the HeLa cells membrane, and showed low cytotoxicity at the imaging concentration.
A new calix[4]arene-based ruthenium(Ⅱ) complex of[Ru2(bpy)4(H2L)](ClO4)4 (1) (bpy=2, 2'-bipyridine and H2L=11, 23-bis(2-imidazo[4, 5-f]-1, 10-phenanthroline)-25, 27-dihydroxy-26, 28-diethoxycarbonylpropyl-5, 17-di-p-t-butyl-calix[4]arene) was synthesized and characterized using an assortment of spectroscopic techniques such as IR, 1H NMR, 13C NMR, ESI-MS, and elementary analysis. The pH luminescence switching property of 1 was studied by means of spectrofluorimetric titrations in CH3CN/Britton-Robinson buffer solution (1: 100, V/V). The complex exhibited two-step separate protonation/deprotonation processes, and acting as a pH-induced "off-on-off" luminescence switch (Ion/Ioff=1.42 and 96.0). The anion sensing properties of complex 1 were thoroughly investigated in solution using absorption, emission, and 1H NMR spectral studies, which revealed that 1 acted as an efficient "turn off" emission sensor for F- and OAc-. Importantly, cellular imaging and cytotoxicity experiments demonstrated that 1 rapidly penetrate through the HeLa cells membrane, and showed low cytotoxicity at the imaging concentration.
2018, 34(2): 263-269
doi: 10.11862/CJIC.2018.044
Abstract:
Fe2P2O7 was prepared from Fe-P waste slag and CO2 using a solid-state method, and it was furtherly used as precursor of LiFePO4. The compositions and microstructures of the as-synthesized Fe2P2O7 and LiFePO4 were characterized by TG/DSC, XRD and SEM. It is found that Fe1.5P can be oxidized to Fe2P2O7 over 700℃ in CO2 atmosphere. The optimized synthesis of Fe2P2O7 is described as:mixture of Fe1.5P and H3PO4 (extra P source) is calcined at 800℃ for 6 h, which gives the highest specific capacity of LiFePO4. The discharge capacity of the as-synthesized LiFePO4 can reach as high as 130, 126, 117, and 108 mAh·g-1 with C-rates of 0.1C, 0.2C, 0.5C and 1C, respectively.
Fe2P2O7 was prepared from Fe-P waste slag and CO2 using a solid-state method, and it was furtherly used as precursor of LiFePO4. The compositions and microstructures of the as-synthesized Fe2P2O7 and LiFePO4 were characterized by TG/DSC, XRD and SEM. It is found that Fe1.5P can be oxidized to Fe2P2O7 over 700℃ in CO2 atmosphere. The optimized synthesis of Fe2P2O7 is described as:mixture of Fe1.5P and H3PO4 (extra P source) is calcined at 800℃ for 6 h, which gives the highest specific capacity of LiFePO4. The discharge capacity of the as-synthesized LiFePO4 can reach as high as 130, 126, 117, and 108 mAh·g-1 with C-rates of 0.1C, 0.2C, 0.5C and 1C, respectively.
2018, 34(2): 277-282
doi: 10.11862/CJIC.2018.056
Abstract:
A Zintl phase compound α-BaZn2P2, was synthesized through the high-temperature Sn-flux reaction. Single-crystal X-ray diffraction was used to accurately determine its structure, which is similar to α-BaCu2S2-type structure (Pnma). The cell parameters of α-BaZn2P2 are a=0.976 78(5) nm, b=0.413 34(2) nm, c=1.060 55(5) nm. Unlike high-temperature-phase β-BaZn2P2, which has a layer structure, low-temperature-phase α-BaZn2P2 has a three-dimensional network structure, where ZnP4 tetrahedra form an anion frame by sharing sides or vertices, with Ba2+ cations residing within. The band structure and state density of the compound were calculated using density functional theory. The results indicate that the compound is a narrow-bandgap semiconductor (Eg=0.4 eV). In addition, differential scanning calorimetry and temperature-dependent XRD results show that α-BaZn2P2 decomposes into binary phases like Ba4P5 and ZnP4 at high temperatures.
A Zintl phase compound α-BaZn2P2, was synthesized through the high-temperature Sn-flux reaction. Single-crystal X-ray diffraction was used to accurately determine its structure, which is similar to α-BaCu2S2-type structure (Pnma). The cell parameters of α-BaZn2P2 are a=0.976 78(5) nm, b=0.413 34(2) nm, c=1.060 55(5) nm. Unlike high-temperature-phase β-BaZn2P2, which has a layer structure, low-temperature-phase α-BaZn2P2 has a three-dimensional network structure, where ZnP4 tetrahedra form an anion frame by sharing sides or vertices, with Ba2+ cations residing within. The band structure and state density of the compound were calculated using density functional theory. The results indicate that the compound is a narrow-bandgap semiconductor (Eg=0.4 eV). In addition, differential scanning calorimetry and temperature-dependent XRD results show that α-BaZn2P2 decomposes into binary phases like Ba4P5 and ZnP4 at high temperatures.
2018, 34(2): 283-288
doi: 10.11862/CJIC.2018.068
Abstract:
Reaction of MnCl2 and 2-dimethylaminoisopropyl chloride hydrochloride afforded one novel molecular-based material, (C5H13ClN)2[MnCl4] (1). And it is interesting to note that 1 exhibits intense greenish fluorescent emission (520 nm) at room temperature and relatively high thermal stability(stable up to 450 K). Moreover, structure and spectra analyses reveal that its excellent optical property can be attributed to the 4T1(G)→6A1 electronic transition of Mn2+ in[MnX4]2- tetrahedron.
Reaction of MnCl2 and 2-dimethylaminoisopropyl chloride hydrochloride afforded one novel molecular-based material, (C5H13ClN)2[MnCl4] (1). And it is interesting to note that 1 exhibits intense greenish fluorescent emission (520 nm) at room temperature and relatively high thermal stability(stable up to 450 K). Moreover, structure and spectra analyses reveal that its excellent optical property can be attributed to the 4T1(G)→6A1 electronic transition of Mn2+ in[MnX4]2- tetrahedron.
2018, 34(2): 230-236
doi: 10.11862/CJIC.2018.037
Abstract:
5, 5'-(1H-1, 2, 4-triazole-1, 4-diyl)diisophthalic acid (H4L) was used to synthesize two microporous three-dimension metal-organic-frameworks(MOFs) with lanthanide metal salts by intermolecular self-assembly:{[Ho3L2(H2O)6]OH·2DMF}n (1), {[Tb3L2(H2O)6]OH·2DMF}n (2). Single-crystal X-ray diffraction revealed the Ln-MOFs are isomorphous and belong to monoclinic C2/m space group. Three Ln(Ⅲ) ions are connected through eight carboxylic groups to form a trinuclear[Ln3(COO)8] SBU. The SBU polyhedrons share edges with each other generating a 1D inorganic chain, and the chains are further connected by the L4- ligands to construct a 3D framework. The luminescence intensity of 2 can be modulated by organic small molecules, and 2 exhibited the significant quenching in nitrobenzene, which indicates that 2 is potential luminescent sensing material for nitro explosives.
5, 5'-(1H-1, 2, 4-triazole-1, 4-diyl)diisophthalic acid (H4L) was used to synthesize two microporous three-dimension metal-organic-frameworks(MOFs) with lanthanide metal salts by intermolecular self-assembly:{[Ho3L2(H2O)6]OH·2DMF}n (1), {[Tb3L2(H2O)6]OH·2DMF}n (2). Single-crystal X-ray diffraction revealed the Ln-MOFs are isomorphous and belong to monoclinic C2/m space group. Three Ln(Ⅲ) ions are connected through eight carboxylic groups to form a trinuclear[Ln3(COO)8] SBU. The SBU polyhedrons share edges with each other generating a 1D inorganic chain, and the chains are further connected by the L4- ligands to construct a 3D framework. The luminescence intensity of 2 can be modulated by organic small molecules, and 2 exhibited the significant quenching in nitrobenzene, which indicates that 2 is potential luminescent sensing material for nitro explosives.
2018, 34(2): 237-246
doi: 10.11862/CJIC.2018.039
Abstract:
Four cadmium-organic coordination polymers, namely[Cd(Hncpoi)(2, 2'-bpy)(H2O)]n (1), {[Cd2(Hncpoi)2(bpyp)(H2O)4]·3H2O}n (2), {[Cd2(Hncpoi)2(azpy)(H2O)2]·2H2O}n (3), {[Cd2(Hncpoi)2(dpe)(H2O)2]·2H2O}n (4), have been solvothermally constructed from multi-carboxylic organic ligand 5-(2-Nitro-4-carboxyphenoxy)-isophthalic acid(H3ncpoi), Cd2+ ions, and different auxiliary ligands:2, 2'-bipyridyl(2, 2'-bpy), 1, 4-bis-(4-pyridylmethyl)piperazine(bpyp), 4, 4'-azopyridine (azpy) and 1, 2-di(4-pyridyl)ethylene(dpe), respectively. These complexes were further characterized by single-crystal X-ray diffraction, PXRD, elemental analysis, and TG. Single-crystal X-ray diffraction showed that complexes 1 and 2 exhibit 1D chain-like structure, and complexes 3 and 4 are 2D (4, 4) grid layered structure. 1D chains or 2D layers of these complexes further assemble to 3D supramolecular architectures via intermolecular interactions. The coordination modes and configurations of secondary ligands have a crucial influence to the crystal structures of these complexes. Meanwhile, the photoluminescent properties of these complexes were also studied. The results showed that there are close relationship between the secondary ligands and photoluminescence properties of these coordination polymers.
Four cadmium-organic coordination polymers, namely[Cd(Hncpoi)(2, 2'-bpy)(H2O)]n (1), {[Cd2(Hncpoi)2(bpyp)(H2O)4]·3H2O}n (2), {[Cd2(Hncpoi)2(azpy)(H2O)2]·2H2O}n (3), {[Cd2(Hncpoi)2(dpe)(H2O)2]·2H2O}n (4), have been solvothermally constructed from multi-carboxylic organic ligand 5-(2-Nitro-4-carboxyphenoxy)-isophthalic acid(H3ncpoi), Cd2+ ions, and different auxiliary ligands:2, 2'-bipyridyl(2, 2'-bpy), 1, 4-bis-(4-pyridylmethyl)piperazine(bpyp), 4, 4'-azopyridine (azpy) and 1, 2-di(4-pyridyl)ethylene(dpe), respectively. These complexes were further characterized by single-crystal X-ray diffraction, PXRD, elemental analysis, and TG. Single-crystal X-ray diffraction showed that complexes 1 and 2 exhibit 1D chain-like structure, and complexes 3 and 4 are 2D (4, 4) grid layered structure. 1D chains or 2D layers of these complexes further assemble to 3D supramolecular architectures via intermolecular interactions. The coordination modes and configurations of secondary ligands have a crucial influence to the crystal structures of these complexes. Meanwhile, the photoluminescent properties of these complexes were also studied. The results showed that there are close relationship between the secondary ligands and photoluminescence properties of these coordination polymers.
2018, 34(2): 247-254
doi: 10.11862/CJIC.2018.043
Abstract:
The oxide nanofiber (Pr0.9La0.1)2(Ni0.74Cu0.21Ga0.05)O4+δ (PLNCG) is prepared by electrospinning technique. The phase and morphology evolution of the oxide nanofiber are characterized by Thermo-gravimetric-Differential thermal analysis (TG-DTA), X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM), respectively. The results show that PLNCG nanofiber with an average diameter of 420 nm is produced after sintering the precursors at 950℃ for 5 h. The nanofiber cathode is formed with mesh-like morphology and keep good contact with the Ce0.9Gd0.1O2-δ (CGO) electrolyte after heat-treated at 1 000℃ for 2 h. The electrochemical impedance spectrum (EIS) results indicate that the nanofiber cathode exhibits superior performance than the powder cathode. The polarization resistance (RP) of the nanofiber cathode is 0.134 Ω·cm2 at 700℃ in air, which is 32% less than the PLNCG powder cathode (RP=0.197 Ω·cm2). The maximum power density of electrolyte-support single cell with PLNCG nanofiber cathode (Ni-CGO/CGO/PLNCG) reaches 231 mW·cm-2 at 700℃. The oxygen partial pressure measurement indicates that the charge transfer process is the reaction rate-limiting step of the nanofiber cathode.
The oxide nanofiber (Pr0.9La0.1)2(Ni0.74Cu0.21Ga0.05)O4+δ (PLNCG) is prepared by electrospinning technique. The phase and morphology evolution of the oxide nanofiber are characterized by Thermo-gravimetric-Differential thermal analysis (TG-DTA), X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM), respectively. The results show that PLNCG nanofiber with an average diameter of 420 nm is produced after sintering the precursors at 950℃ for 5 h. The nanofiber cathode is formed with mesh-like morphology and keep good contact with the Ce0.9Gd0.1O2-δ (CGO) electrolyte after heat-treated at 1 000℃ for 2 h. The electrochemical impedance spectrum (EIS) results indicate that the nanofiber cathode exhibits superior performance than the powder cathode. The polarization resistance (RP) of the nanofiber cathode is 0.134 Ω·cm2 at 700℃ in air, which is 32% less than the PLNCG powder cathode (RP=0.197 Ω·cm2). The maximum power density of electrolyte-support single cell with PLNCG nanofiber cathode (Ni-CGO/CGO/PLNCG) reaches 231 mW·cm-2 at 700℃. The oxygen partial pressure measurement indicates that the charge transfer process is the reaction rate-limiting step of the nanofiber cathode.
2018, 34(2): 255-262
doi: 10.11862/CJIC.2018.051
Abstract:
The CdTe and CdS nanocrystals were deposited on the TiO2 nanotube arrays by electrodeposition and chemical bath deposition method to obtain CdTe/CdS nanocrystals co-sensitized TiO2 photoelectrodes. The morphology, crystallinity and composition of samples were characterized by SEM, XRD and EDS. Under standard solar light irradiation, the photoelectrochemical performance of resulted photoelectrodes were investigated by means of electrochemical work station. The results show that the photoelectric conversion performance of co-sensitized CdTe/CdS/TiO2 photoelectrodes exhibit more excellent performance than that of single-sensitized CdS/TiO2 and CdTe/TiO2 based photoelectrodes. The short circuit photocurrent density and photoelectric conversion efficiency of CdTe/CdS/TiO2 could reach up to 3.1 mA·cm-2 and 1.85%, respectively. Meanwhile, the electrochemical impedance test has also been applied to further investigate the principle of enhanced performance.
The CdTe and CdS nanocrystals were deposited on the TiO2 nanotube arrays by electrodeposition and chemical bath deposition method to obtain CdTe/CdS nanocrystals co-sensitized TiO2 photoelectrodes. The morphology, crystallinity and composition of samples were characterized by SEM, XRD and EDS. Under standard solar light irradiation, the photoelectrochemical performance of resulted photoelectrodes were investigated by means of electrochemical work station. The results show that the photoelectric conversion performance of co-sensitized CdTe/CdS/TiO2 photoelectrodes exhibit more excellent performance than that of single-sensitized CdS/TiO2 and CdTe/TiO2 based photoelectrodes. The short circuit photocurrent density and photoelectric conversion efficiency of CdTe/CdS/TiO2 could reach up to 3.1 mA·cm-2 and 1.85%, respectively. Meanwhile, the electrochemical impedance test has also been applied to further investigate the principle of enhanced performance.
2018, 34(2): 270-276
doi: 10.11862/CJIC.2018.057
Abstract:
Aimed in the development of functionalized nitrogen ligands, a series of novel 2, 9-dialkoxyl-4, 7-diphenyl-1, 10-phenanthroline ligands 5a~5e were designed and synthesized from 4, 7-diphenyl-1, 10-phenanthroline under quaternization, oxidation, halogenation and etherification. Then using Xantphos as phosphorus ligands, a series of heteroleptic copper photosensitizers (CuPS A~H) were obtained by the in-situ method. In homogeneous photocatalytic water reduction system, their photosensitive activity for hydrogen production was studied. Research results show that 2, 9-diethoxy is the preferred substituent and the turnover number for hydrogen production (TON) of CuPS D is up to 270. In the analysis of photoelectric physical properties, it is found that this kind of heteroleptic copper complexes have a pair of similar redox potentials (Eoxd=-0.8 V, Ered=-1.2 V). Compared with other substituents in Cu-based complexes, CuPS D shows the weakest fluorescence, which indicates the ethoxy substituent could improve the photochemical conversion ability of CuPS by increasing the fluorescence quenching efficiency.
Aimed in the development of functionalized nitrogen ligands, a series of novel 2, 9-dialkoxyl-4, 7-diphenyl-1, 10-phenanthroline ligands 5a~5e were designed and synthesized from 4, 7-diphenyl-1, 10-phenanthroline under quaternization, oxidation, halogenation and etherification. Then using Xantphos as phosphorus ligands, a series of heteroleptic copper photosensitizers (CuPS A~H) were obtained by the in-situ method. In homogeneous photocatalytic water reduction system, their photosensitive activity for hydrogen production was studied. Research results show that 2, 9-diethoxy is the preferred substituent and the turnover number for hydrogen production (TON) of CuPS D is up to 270. In the analysis of photoelectric physical properties, it is found that this kind of heteroleptic copper complexes have a pair of similar redox potentials (Eoxd=-0.8 V, Ered=-1.2 V). Compared with other substituents in Cu-based complexes, CuPS D shows the weakest fluorescence, which indicates the ethoxy substituent could improve the photochemical conversion ability of CuPS by increasing the fluorescence quenching efficiency.
2018, 34(2): 289-294
doi: 10.11862/CJIC.2018.033
Abstract:
1D Ag-doped ZnO nanorods (NRs) have been synthesized on p-GaN films using a facile hydrothermal method, and investigated the effect of the Ag doping on the morphology and structure of the NRs and the optical performances of the n-ZnO NRs/p-GaN heterojunction. The results show that the section of ZnO nanorods is hexagon and ZnO nanorods were vertically grown on the p-GaN film. The XRD analysis shows that the (002) peak of the 1D ZnO NRs shifted toward a lower 2θ with increasing the Ag content, indicating that the substitution of the Ag ions with the Zn ions leads to expansion of the ZnO lattice. With the increase of Ag doping concentration, the near band edge emission peak of ZnO nanorods shows a redshift, the intensity of near band edge emission peak weakened gradually and the intensity of yellow band emission peak has the opposite trend, and n-ZnO nanorods/p-GaN heterojunction reveals a better transmission efficiency.
1D Ag-doped ZnO nanorods (NRs) have been synthesized on p-GaN films using a facile hydrothermal method, and investigated the effect of the Ag doping on the morphology and structure of the NRs and the optical performances of the n-ZnO NRs/p-GaN heterojunction. The results show that the section of ZnO nanorods is hexagon and ZnO nanorods were vertically grown on the p-GaN film. The XRD analysis shows that the (002) peak of the 1D ZnO NRs shifted toward a lower 2θ with increasing the Ag content, indicating that the substitution of the Ag ions with the Zn ions leads to expansion of the ZnO lattice. With the increase of Ag doping concentration, the near band edge emission peak of ZnO nanorods shows a redshift, the intensity of near band edge emission peak weakened gradually and the intensity of yellow band emission peak has the opposite trend, and n-ZnO nanorods/p-GaN heterojunction reveals a better transmission efficiency.
2018, 34(2): 295-299
doi: 10.11862/CJIC.2018.031
Abstract:
La-containing metallofullerenes were synthesized with a direct current arc-discharge method, and the experimental conditions such as helium pressure and current density were optimized to improve the yield of metallofullerenes (La@C2v-C82, La@Cs-C82 and La2@C80). The raw soot was extracted by 1, 2, 4-trichlorobenzene and was then redissolved in toluene. The yields of the La-containing metallofullerenes were discussed based on the high performance liquid chromatographic results by comparing their peak areas with that of C84. Experimental results show that the high yield of La@C82 can be attributed to a synergetic effect of current density and He pressure, i.e. (1) low current and high He pressure; (2) medium current and medium He pressure; and (3) high current and low He pressure. Furthermore, the relative ratio of La@C2v-C82 and La@Cs-C82 can be adjusted by changing the current density and He pressure. Surprisingly, it is discovered that low current density or low He pressure facilitates the formation of La2@C80, indicating that the formation process of La2@C80 may be different from that of La@C82.
La-containing metallofullerenes were synthesized with a direct current arc-discharge method, and the experimental conditions such as helium pressure and current density were optimized to improve the yield of metallofullerenes (La@C2v-C82, La@Cs-C82 and La2@C80). The raw soot was extracted by 1, 2, 4-trichlorobenzene and was then redissolved in toluene. The yields of the La-containing metallofullerenes were discussed based on the high performance liquid chromatographic results by comparing their peak areas with that of C84. Experimental results show that the high yield of La@C82 can be attributed to a synergetic effect of current density and He pressure, i.e. (1) low current and high He pressure; (2) medium current and medium He pressure; and (3) high current and low He pressure. Furthermore, the relative ratio of La@C2v-C82 and La@Cs-C82 can be adjusted by changing the current density and He pressure. Surprisingly, it is discovered that low current density or low He pressure facilitates the formation of La2@C80, indicating that the formation process of La2@C80 may be different from that of La@C82.
2018, 34(2): 300-308
doi: 10.11862/CJIC.2018.046
Abstract:
SAPO-34 is prone to losing its activity during methanol to olefins (MTO). Hierarchical SAPO-34 with different particles size was synthesized in a hydrothermal procedure. The factors controlling the size of SAPO-34 zeolite such as aluminum species and silicon species, and the effect of secondary template on the synthesis of hierarchical SAPO-34 were investigated in details. The as-synthesized samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, N2 adsorption-desorption, transmission electron microscopy (TEM), and NH3-TPD techniques. The results displayed that the different silicon species can tailor the crystalline size effectively, Secondary template can give the as-synthesized SAPO-34 a mesopore structure with crystalline walls, which contributes to enhancing the thermostability, especially the hydrothermal stability during the MTO process. The catalytic performance of the as-synthesized SAPO-34 was investigated during the MTO, as compared with the referenced SAPO-34-R, hierarchical SAPO-34 displayed an excellent catalytic performance during the MTO by giving a prolonged catalytic life and an elevated selectivity for oil while a depressed olefins selectivity because of the shortened microporous channel length caused by the nanocrystallization or the introduced mesopore system.
SAPO-34 is prone to losing its activity during methanol to olefins (MTO). Hierarchical SAPO-34 with different particles size was synthesized in a hydrothermal procedure. The factors controlling the size of SAPO-34 zeolite such as aluminum species and silicon species, and the effect of secondary template on the synthesis of hierarchical SAPO-34 were investigated in details. The as-synthesized samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, N2 adsorption-desorption, transmission electron microscopy (TEM), and NH3-TPD techniques. The results displayed that the different silicon species can tailor the crystalline size effectively, Secondary template can give the as-synthesized SAPO-34 a mesopore structure with crystalline walls, which contributes to enhancing the thermostability, especially the hydrothermal stability during the MTO process. The catalytic performance of the as-synthesized SAPO-34 was investigated during the MTO, as compared with the referenced SAPO-34-R, hierarchical SAPO-34 displayed an excellent catalytic performance during the MTO by giving a prolonged catalytic life and an elevated selectivity for oil while a depressed olefins selectivity because of the shortened microporous channel length caused by the nanocrystallization or the introduced mesopore system.
2018, 34(2): 309-316
doi: 10.11862/CJIC.2018.028
Abstract:
A five-coordinated binuclear cobalt(Ⅱ) complex with the formula[Co2(H2O)2(L1)2(4, 4'-bipy)] (1) (H2L1=2-hydroxybenzene (2-hydroxyl-5-nitro-phenyl-methyl) amine) was hydrothermally synthesized and a binuclear nickel(Ⅱ) complex of general formula[Ni2(L2)2(4, 4'-bipy)] (2) (H2L2=2-hydroxybenzene (2-hydroxyl-phenyl-methyl) amine) synthesized by using evaporation method, and the comlexes were characterized by IR, UV-Vis spectra and TGA. The X-ray diffraction analyses reveal that 1 crystallizes in the triclinic space group P1 while 2 in trigonal space group R3. The antitumor activity in vitro of ligands and complexes were measured by MTT method, and the results show that the complexes 1 and 2 possess inhibiting effects to HEPG2 and SW620 cancer cells lines. The quantum chemical calculation for 2 was performed by means of Gaussian 09 program at UB3LYP/6-31G(d) basis set. CCDC: 1440518, 1; 1432468, 2.
A five-coordinated binuclear cobalt(Ⅱ) complex with the formula[Co2(H2O)2(L1)2(4, 4'-bipy)] (1) (H2L1=2-hydroxybenzene (2-hydroxyl-5-nitro-phenyl-methyl) amine) was hydrothermally synthesized and a binuclear nickel(Ⅱ) complex of general formula[Ni2(L2)2(4, 4'-bipy)] (2) (H2L2=2-hydroxybenzene (2-hydroxyl-phenyl-methyl) amine) synthesized by using evaporation method, and the comlexes were characterized by IR, UV-Vis spectra and TGA. The X-ray diffraction analyses reveal that 1 crystallizes in the triclinic space group P1 while 2 in trigonal space group R3. The antitumor activity in vitro of ligands and complexes were measured by MTT method, and the results show that the complexes 1 and 2 possess inhibiting effects to HEPG2 and SW620 cancer cells lines. The quantum chemical calculation for 2 was performed by means of Gaussian 09 program at UB3LYP/6-31G(d) basis set. CCDC: 1440518, 1; 1432468, 2.
2018, 34(2): 317-324
doi: 10.11862/CJIC.2018.030
Abstract:
Mn4+ doped Co3O4 nanofibers with nCo:nMn=20:2 have large surface with 68 m2·g-1. Under the current density of 1 A·g-1, the 20:2 sample has a maximum capacitance of 585 F·g-1, which is obviously higher than that of pure cobalt oxide nanofiber~416 F·g-1. After 500 cycles of charging and discharging, the specific capacitance of 20:2 sample is maintained about 82.6%, but that of the pure cobalt oxide nanofiber is only 76.4%. The mechanism of performance improvement of the composite fibers was analyzed concretely.
Mn4+ doped Co3O4 nanofibers with nCo:nMn=20:2 have large surface with 68 m2·g-1. Under the current density of 1 A·g-1, the 20:2 sample has a maximum capacitance of 585 F·g-1, which is obviously higher than that of pure cobalt oxide nanofiber~416 F·g-1. After 500 cycles of charging and discharging, the specific capacitance of 20:2 sample is maintained about 82.6%, but that of the pure cobalt oxide nanofiber is only 76.4%. The mechanism of performance improvement of the composite fibers was analyzed concretely.
2018, 34(2): 325-330
doi: 10.11862/CJIC.2018.066
Abstract:
The high pure B2O3-CaO:Eu3+ phosphor is prepared by sol-gel method. The structures of samples obtained at different annealing temperatures are characterized by XRD and IR. It is found that the borate matrix with different structures can be formed with the change of annealing temperature. Based on the analysis of the excitation spectrum, emission spectrum and fluorescence decay curves of borate phosphors with different structures, the luminescent properties and luminescent mechanism of the phosphors are investigated. The result indicate that Eu3+ ions occupy no inversion symmetry site with the dominant electric dipole transition in borate matrix of the different structure, and these phosphors give off red light under ultraviolet excitation. The high pure CaB2O4 matrix obtained by annealing at 900℃ is most favorable for luminescence and the B2O3-CaO:Eu3+ phosphor have the longest fluorescence decay time. These are attributed to the fact that Eu3+ in the matrix is more likely to replace Ca2+ to form relatively large numbers of p-n junctions and traps.
The high pure B2O3-CaO:Eu3+ phosphor is prepared by sol-gel method. The structures of samples obtained at different annealing temperatures are characterized by XRD and IR. It is found that the borate matrix with different structures can be formed with the change of annealing temperature. Based on the analysis of the excitation spectrum, emission spectrum and fluorescence decay curves of borate phosphors with different structures, the luminescent properties and luminescent mechanism of the phosphors are investigated. The result indicate that Eu3+ ions occupy no inversion symmetry site with the dominant electric dipole transition in borate matrix of the different structure, and these phosphors give off red light under ultraviolet excitation. The high pure CaB2O4 matrix obtained by annealing at 900℃ is most favorable for luminescence and the B2O3-CaO:Eu3+ phosphor have the longest fluorescence decay time. These are attributed to the fact that Eu3+ in the matrix is more likely to replace Ca2+ to form relatively large numbers of p-n junctions and traps.
2018, 34(2): 331-336
doi: 10.11862/CJIC.2018.042
Abstract:
Large-scale Sb doped ZnO microwire arrays were grown by chemical vapor deposition method without using metal catalyst. The experimental results show that the length of the microwires is about 1~2.5 cm and the Sb concentration in microwires is about 3.1%(n/n). Moreover, thermoelectric generators were fabricated based on single Sb doped large-scale ZnO microwires. The influence of the length and diameter of microwires on the output characteristics of devices was investigated. Under a temperature difference of 20 K between two electrodes and the length of 1.6 cm, the devices can produce a maximum output voltage of about 36 mV, a maximum output power of about 10.8 nW. The single Sb-doped ZnO microwires show a Seebeck coefficient of about -1.80 mV·K-1. In addition, it is found that the output voltages of the thermoelectric device increase with the microwire length, and decrease with the microwire diameters.
Large-scale Sb doped ZnO microwire arrays were grown by chemical vapor deposition method without using metal catalyst. The experimental results show that the length of the microwires is about 1~2.5 cm and the Sb concentration in microwires is about 3.1%(n/n). Moreover, thermoelectric generators were fabricated based on single Sb doped large-scale ZnO microwires. The influence of the length and diameter of microwires on the output characteristics of devices was investigated. Under a temperature difference of 20 K between two electrodes and the length of 1.6 cm, the devices can produce a maximum output voltage of about 36 mV, a maximum output power of about 10.8 nW. The single Sb-doped ZnO microwires show a Seebeck coefficient of about -1.80 mV·K-1. In addition, it is found that the output voltages of the thermoelectric device increase with the microwire length, and decrease with the microwire diameters.
2018, 34(2): 337-345
doi: 10.11862/CJIC.2018.041
Abstract:
MoO3 interlayered Fe3O4@MoO3@mSiO2 core-spacer-shell structured drug nanocarrier was constructed to investigate loading and controllable release properties of ibuprofen (IBU). They possess high surface area of 222 cm2·g-1, provide large accessible pore volume of 0.14 cm3·g-1 for adsorption of drug molecules. At the same time they also have good magnetic responsiveness for drug targeting under foreigen magnetic under foreign magnetic fields, relatively good microwave heating conversion behavior for controlled release by microwave-triggered which is caused by MoO3 interlayer. The IBU release of over 86% under microwave discontinuous irradiation within 360 min outclasses the only stirring release.
MoO3 interlayered Fe3O4@MoO3@mSiO2 core-spacer-shell structured drug nanocarrier was constructed to investigate loading and controllable release properties of ibuprofen (IBU). They possess high surface area of 222 cm2·g-1, provide large accessible pore volume of 0.14 cm3·g-1 for adsorption of drug molecules. At the same time they also have good magnetic responsiveness for drug targeting under foreigen magnetic under foreign magnetic fields, relatively good microwave heating conversion behavior for controlled release by microwave-triggered which is caused by MoO3 interlayer. The IBU release of over 86% under microwave discontinuous irradiation within 360 min outclasses the only stirring release.
2018, 34(2): 346-352
doi: 10.11862/CJIC.2018.048
Abstract:
A series of cyclometalated iridium(Ⅲ) complexes:[(PPM)2Ir(bpy)]PF6 (1), [(MPPM)2Ir(bpy)]PF6 (2), [(DFPPM)2Ir(bpy)]PF6 (3), [(MDFPPM)2Ir(bpy)]PF6 (4) (PPM=2-phenylpyrimidine, MPPM=4, 6-dimethyl-2-phenyl-pyrimidine, DFPPM=2-(2, 4-difluorophenyl)pyrimidine, MDFPPM=2-(2, 4-difluorophenyl)-4, 6-dimethylpyrimidine, bpy=2, 2'-bipyridine) were synthesized with pyrimidine compounds as cyclometalated ligand and 2, 2'-bipyridine as ancillary ligand. New iridium(Ⅲ) complexes were characterized by the NMR and mass spectroscopies, and the single crystal structures of complex 4 was measured. The photophysical properties of the complexes were studied by ultraviolet-visble (UV-Vis) absorption, photoluminescence and time-dependent density functionaltheory (TD-DFT) calculation. X-ray diffraction studies have revealed that complex 4 belongs to monoclinic system with space group of P21/c. A theoretical calculation reveals that the HOMO of 3 and 4 is mainly distributed on the iridium ion and the phenyl group of the cyclometalated ligands, while the LUMO is mainly centered on the ancillary ligand bpy. In CH2Cl2 solution, the iridium(Ⅲ) complexes 1 and 2 exhibit yellow-green emissions with peak at 561 and 572 nm, respectively, while the iridium(Ⅲ) complexes 3 and 4 exhibit green emissions with peak at 501 and 513 nm, respectively. The iridium(Ⅲ) complexes had quantum efficiencies between 6.7% and 64.0%.
A series of cyclometalated iridium(Ⅲ) complexes:[(PPM)2Ir(bpy)]PF6 (1), [(MPPM)2Ir(bpy)]PF6 (2), [(DFPPM)2Ir(bpy)]PF6 (3), [(MDFPPM)2Ir(bpy)]PF6 (4) (PPM=2-phenylpyrimidine, MPPM=4, 6-dimethyl-2-phenyl-pyrimidine, DFPPM=2-(2, 4-difluorophenyl)pyrimidine, MDFPPM=2-(2, 4-difluorophenyl)-4, 6-dimethylpyrimidine, bpy=2, 2'-bipyridine) were synthesized with pyrimidine compounds as cyclometalated ligand and 2, 2'-bipyridine as ancillary ligand. New iridium(Ⅲ) complexes were characterized by the NMR and mass spectroscopies, and the single crystal structures of complex 4 was measured. The photophysical properties of the complexes were studied by ultraviolet-visble (UV-Vis) absorption, photoluminescence and time-dependent density functionaltheory (TD-DFT) calculation. X-ray diffraction studies have revealed that complex 4 belongs to monoclinic system with space group of P21/c. A theoretical calculation reveals that the HOMO of 3 and 4 is mainly distributed on the iridium ion and the phenyl group of the cyclometalated ligands, while the LUMO is mainly centered on the ancillary ligand bpy. In CH2Cl2 solution, the iridium(Ⅲ) complexes 1 and 2 exhibit yellow-green emissions with peak at 561 and 572 nm, respectively, while the iridium(Ⅲ) complexes 3 and 4 exhibit green emissions with peak at 501 and 513 nm, respectively. The iridium(Ⅲ) complexes had quantum efficiencies between 6.7% and 64.0%.
2018, 34(2): 353-358
doi: 10.11862/CJIC.2018.050
Abstract:
Taken chiral induction as the breakthrough point, the cholesterol-containing ammonium surfactant is employed to encapsulate the lacunary Keggin-type polyoxometalate, which yielding a chiral mesogenic cations modified polyoxometalate-containing hybrid supramolecular complex. The complex has optical activities which are induced by the peripheral chiral surfactants through electrostatic interactions, as demonstrated by the circular dichroism spectrum. The thermotropic behaviors of the complex are characterized by differential scanning calorimetry, polarized optical microscopy, and temperature-dependent X-ray diffraction, which indicating that the complex has liquid crystalline properties with a typical SmA* mesophase over a wide temperature range.
Taken chiral induction as the breakthrough point, the cholesterol-containing ammonium surfactant is employed to encapsulate the lacunary Keggin-type polyoxometalate, which yielding a chiral mesogenic cations modified polyoxometalate-containing hybrid supramolecular complex. The complex has optical activities which are induced by the peripheral chiral surfactants through electrostatic interactions, as demonstrated by the circular dichroism spectrum. The thermotropic behaviors of the complex are characterized by differential scanning calorimetry, polarized optical microscopy, and temperature-dependent X-ray diffraction, which indicating that the complex has liquid crystalline properties with a typical SmA* mesophase over a wide temperature range.
2018, 34(2): 359-366
doi: 10.11862/CJIC.2018.062
Abstract:
The rare earth ion Tm3+ doped Bi2WO6 photocatalyst was synthesized by hydrothermal method using Na2WO4·2H2O and Bi(NO3)3·5H2O as the main raw materials. The phase, microstructure and visible light proper-ties of Tm3+ doped Bi2WO6 were studied by XRD, SEM, TEM, Raman, PL and DRS. The results show that the photocatalytic performance of Bi2WO6 is improved by Tm3+ ion doping. When the doping amount is 6%, the photo-catalytic performance of the sample is the best, and the degradation efficiency of Rhodamine B is 91.27% after 30 minutes of visible light irradiation, After 5 hours of visible light irradiation, the degradation efficiency of the carculin was 45.25%. Compared with undoped Bi2WO6, the degradation rate is increased 27.78% and 35.22%, respectively.
The rare earth ion Tm3+ doped Bi2WO6 photocatalyst was synthesized by hydrothermal method using Na2WO4·2H2O and Bi(NO3)3·5H2O as the main raw materials. The phase, microstructure and visible light proper-ties of Tm3+ doped Bi2WO6 were studied by XRD, SEM, TEM, Raman, PL and DRS. The results show that the photocatalytic performance of Bi2WO6 is improved by Tm3+ ion doping. When the doping amount is 6%, the photo-catalytic performance of the sample is the best, and the degradation efficiency of Rhodamine B is 91.27% after 30 minutes of visible light irradiation, After 5 hours of visible light irradiation, the degradation efficiency of the carculin was 45.25%. Compared with undoped Bi2WO6, the degradation rate is increased 27.78% and 35.22%, respectively.
2018, 34(2): 367-374
doi: 10.11862/CJIC.2018.054
Abstract:
The complex Mn[(IPB)2Cl2]·4H2O (IPB=4-(1H-imidazo[4, 5-f] [1, 10]phenanthrolin-2-yl) benzaldehyde) was synthesized and characterized by elemental analysis, IR, UV-Vis, X-ray diffraction and the Z-scan technique. The X-ray diffraction results revealed that the complex crystallizes in Pnna space group of orthorhombic crystal system. The nonlinear optical properties were measured by the Z-scan technique and yielded a normalized transmittance of about 93% for the complex with a 45 μJ pulse at the focal point, and the nonlinear absorption coefficient, β, is -4.5×10-11 m·W-1, the nonlinear refractive index, γ, is 1.0×10-19 m2·W-1. The complex shows a self-focusing property. In the range of the UV-Vis spectrum, the maximum absorption wavelength is at 282 nm for the complex.
The complex Mn[(IPB)2Cl2]·4H2O (IPB=4-(1H-imidazo[4, 5-f] [1, 10]phenanthrolin-2-yl) benzaldehyde) was synthesized and characterized by elemental analysis, IR, UV-Vis, X-ray diffraction and the Z-scan technique. The X-ray diffraction results revealed that the complex crystallizes in Pnna space group of orthorhombic crystal system. The nonlinear optical properties were measured by the Z-scan technique and yielded a normalized transmittance of about 93% for the complex with a 45 μJ pulse at the focal point, and the nonlinear absorption coefficient, β, is -4.5×10-11 m·W-1, the nonlinear refractive index, γ, is 1.0×10-19 m2·W-1. The complex shows a self-focusing property. In the range of the UV-Vis spectrum, the maximum absorption wavelength is at 282 nm for the complex.
2018, 34(2): 375-380
doi: 10.11862/CJIC.2018.032
Abstract:
Three complexes, namely {[Zn(HL)(H2O)(SO4)]·H2O}n (1), [Cd(HL)Cl2] (2) and[Cd(HL)I2] (3) (HL=N-((quinolin-8-yl)methylene)acetohydrazide) have been synthesized and characterized by single crystal X-ray diffraction, elemental analysis and IR spectroscopy. X-ray diffraction analysis results show that in complex 1, the Zn(Ⅱ) ion with a distorted octahedron coordination geometry is six-coordinated, involving one coordinated water molecule, one ONN donor set of an neutral ligand HL, and two O atoms from two independent μ2-bridged sulfate anions, thus forming one dimension chain-like framework along b axis. However, the coordination geometry of the Cd(Ⅱ) ion in each of complexes 2 and 3 is a distorted square planar geometry with a tridentate acylhydrazone ligand and two halide anions (chloride for 2, while iodide for 3). In CH3CN solution, the ligand HL and complex 3 exhibit almost none fluorescence emission, whilst complexes 1 and 2 show remarkable peaks at about 428 and 408 nm, respectively.
Three complexes, namely {[Zn(HL)(H2O)(SO4)]·H2O}n (1), [Cd(HL)Cl2] (2) and[Cd(HL)I2] (3) (HL=N-((quinolin-8-yl)methylene)acetohydrazide) have been synthesized and characterized by single crystal X-ray diffraction, elemental analysis and IR spectroscopy. X-ray diffraction analysis results show that in complex 1, the Zn(Ⅱ) ion with a distorted octahedron coordination geometry is six-coordinated, involving one coordinated water molecule, one ONN donor set of an neutral ligand HL, and two O atoms from two independent μ2-bridged sulfate anions, thus forming one dimension chain-like framework along b axis. However, the coordination geometry of the Cd(Ⅱ) ion in each of complexes 2 and 3 is a distorted square planar geometry with a tridentate acylhydrazone ligand and two halide anions (chloride for 2, while iodide for 3). In CH3CN solution, the ligand HL and complex 3 exhibit almost none fluorescence emission, whilst complexes 1 and 2 show remarkable peaks at about 428 and 408 nm, respectively.
2018, 34(2): 381-386
doi: 10.11862/CJIC.2018.034
Abstract:
Two novel silver(Ⅰ) complexes[Ag(XANTphos)]BF4 (1) and [Ag2Cl2(DPEphos)2]·2CH2Cl2 (2) (XANTphos=9, 9-dimethyl-4, 5-bis(diphenylphosphanyl)xanthene, DPEphos=bis(2-(diphenylphosphino)phenyl)ether) have been synthesized in mixed solvent CH3OH and CH2Cl2 and characterized by IR, single-crystal X-ray diffraction, 1H NMR spectroscopy and fluorescence spectra. Complex 1 is of a mononuclear complex, which was generated by the reaction of AgBF4 and XANTphos with dmp (neocuproine) in 1:1:1 molar ratio. The central ion Ag(Ⅰ) forms a ring by the chelating bisphosphine ligand (XANTphos). While complex 2 is of a binuclear complex, which was obtained by the reaction of AgCl with DPEphos in 1:1 molar ratio. In the asymmetric unit of complex 2, each DPEphos ligand chelates one silver(Ⅰ) cation with a free dichloromethane. The luminescent spectra show that all the emissions of the complexes 1 and 2 are assigned to ligand centered π-π* transition.
Two novel silver(Ⅰ) complexes[Ag(XANTphos)]BF4 (1) and [Ag2Cl2(DPEphos)2]·2CH2Cl2 (2) (XANTphos=9, 9-dimethyl-4, 5-bis(diphenylphosphanyl)xanthene, DPEphos=bis(2-(diphenylphosphino)phenyl)ether) have been synthesized in mixed solvent CH3OH and CH2Cl2 and characterized by IR, single-crystal X-ray diffraction, 1H NMR spectroscopy and fluorescence spectra. Complex 1 is of a mononuclear complex, which was generated by the reaction of AgBF4 and XANTphos with dmp (neocuproine) in 1:1:1 molar ratio. The central ion Ag(Ⅰ) forms a ring by the chelating bisphosphine ligand (XANTphos). While complex 2 is of a binuclear complex, which was obtained by the reaction of AgCl with DPEphos in 1:1 molar ratio. In the asymmetric unit of complex 2, each DPEphos ligand chelates one silver(Ⅰ) cation with a free dichloromethane. The luminescent spectra show that all the emissions of the complexes 1 and 2 are assigned to ligand centered π-π* transition.
2018, 34(2): 387-396
doi: 10.11862/CJIC.2018.036
Abstract:
A series of mononuclear complexes named[(bpy)Pd(L)]NO3 (1·NO3·H2O), [(bpy)Pt(L)]NO3 (2·NO3·H2O), and[(phen)Pd(L)]NO3 (3·NO3·H2O) (where bpy=2, 2'-bipyridine, phen=1, 10-phenanthroline) have been self-assembled through a directed coordination approach that involves spontaneous deprotonation of the 1, 3-diphenylpropane-1, 3-dione (L) in aqueous solution driven by coordination effect. NO3- in these assemblies can be effectively replaced by PF6- in a solution of KPF6. All of these new mononuclear complexes have been fully characterized by 1H NMR, 13C NMR and ESI-MS analysis. X-ray diffraction analysis of 1·PF6·CH3CN clearly shows that a dimeric crystal structure is formed by the π-π stacking interactions and weak intramolecular Pd…Pd (0.322 4 nm) interactions. More importantly, all of these three assemblies can be employed as a new kind of high-efficiency catalysts for Suzuki-coupling reaction.
A series of mononuclear complexes named[(bpy)Pd(L)]NO3 (1·NO3·H2O), [(bpy)Pt(L)]NO3 (2·NO3·H2O), and[(phen)Pd(L)]NO3 (3·NO3·H2O) (where bpy=2, 2'-bipyridine, phen=1, 10-phenanthroline) have been self-assembled through a directed coordination approach that involves spontaneous deprotonation of the 1, 3-diphenylpropane-1, 3-dione (L) in aqueous solution driven by coordination effect. NO3- in these assemblies can be effectively replaced by PF6- in a solution of KPF6. All of these new mononuclear complexes have been fully characterized by 1H NMR, 13C NMR and ESI-MS analysis. X-ray diffraction analysis of 1·PF6·CH3CN clearly shows that a dimeric crystal structure is formed by the π-π stacking interactions and weak intramolecular Pd…Pd (0.322 4 nm) interactions. More importantly, all of these three assemblies can be employed as a new kind of high-efficiency catalysts for Suzuki-coupling reaction.
2018, 34(2): 397-403
doi: 10.11862/CJIC.2018.015
Abstract:
The fabrication and characterization of Ag-NaTaO3-reduced graphene oxide (RGO) composite as an effective photocatalyst are presented. The Ag-NaTaO3-RGO composites with enhanced photocatalytic efficiency were synthesized by a three-step method. The photocatalytic activity of the samples was evaluated by photocatalytic water splitting hydrogen-evolution under ultraviolet light irradiation. Compared with NaTaO3, Ag-NaTaO3, and NaTaO3-RGO, the as-prepared 0.2Ag-NaTaO3-RGO composite exhibits the highest H2 production rate which was around 5.64, 1.97 and 1.48 times higher than that of pure NaTaO3, Ag-NaTaO3 and NaTaO3-RGO. The enhancement of H2 production can be mainly attributed to the following three factors:(ⅰ) the efficient separation of electron-hole pairs originated from the excellent electron transfer property of graphene. (ⅱ) the further improvement of electron-hole separation rate due to Ag nanoparticle acted as electron traps. (ⅲ) the enhancement of light absorption over the entire range of wavelengths with the introduction of graphene. In addition, plausible mechanism for the enhanced photocatalytic hydrogen production over the Ag-NaTaO3-RGO composite was proposed. This work demonstrates that rational composite of two or more phases of semiconductor should be a good strategy to design efficient photocatalysts.
The fabrication and characterization of Ag-NaTaO3-reduced graphene oxide (RGO) composite as an effective photocatalyst are presented. The Ag-NaTaO3-RGO composites with enhanced photocatalytic efficiency were synthesized by a three-step method. The photocatalytic activity of the samples was evaluated by photocatalytic water splitting hydrogen-evolution under ultraviolet light irradiation. Compared with NaTaO3, Ag-NaTaO3, and NaTaO3-RGO, the as-prepared 0.2Ag-NaTaO3-RGO composite exhibits the highest H2 production rate which was around 5.64, 1.97 and 1.48 times higher than that of pure NaTaO3, Ag-NaTaO3 and NaTaO3-RGO. The enhancement of H2 production can be mainly attributed to the following three factors:(ⅰ) the efficient separation of electron-hole pairs originated from the excellent electron transfer property of graphene. (ⅱ) the further improvement of electron-hole separation rate due to Ag nanoparticle acted as electron traps. (ⅲ) the enhancement of light absorption over the entire range of wavelengths with the introduction of graphene. In addition, plausible mechanism for the enhanced photocatalytic hydrogen production over the Ag-NaTaO3-RGO composite was proposed. This work demonstrates that rational composite of two or more phases of semiconductor should be a good strategy to design efficient photocatalysts.
2018, 34(2): 404-408
doi: 10.11862/CJIC.2018.055
Abstract:
Two homogeneous compounds, {(4-CH3-Bz-4-Ph-Py)[PbBr3]}n (1) (4-CH3-Bz-4-Ph-Py+=4-methylbenzyl-4-phenylpyridinium) and {(4-F-Bz-4-Ph-Py)[PbBr3]}n (2) (4-F-Bz-4-Ph-Py+=4-fluorobenzyl-4-phenylpyridinium), have been synthesized and characterized by elemental analysis and single-crystal X-ray diffraction. Compounds 1 and 2 are isostructural, and crystallize in orthorhombic, space group P21212. Structure analyses reveals that haloplumbate ion exhibits octahedron topology in compounds 1 and 2, and all these octahedron topologies formed 1D polymeric chain through edge-sharing connecting modes. The flack values of 1 and 2 are 0.340(13) and 0.453(10), respectively. No chiral separation was done for both compounds.
Two homogeneous compounds, {(4-CH3-Bz-4-Ph-Py)[PbBr3]}n (1) (4-CH3-Bz-4-Ph-Py+=4-methylbenzyl-4-phenylpyridinium) and {(4-F-Bz-4-Ph-Py)[PbBr3]}n (2) (4-F-Bz-4-Ph-Py+=4-fluorobenzyl-4-phenylpyridinium), have been synthesized and characterized by elemental analysis and single-crystal X-ray diffraction. Compounds 1 and 2 are isostructural, and crystallize in orthorhombic, space group P21212. Structure analyses reveals that haloplumbate ion exhibits octahedron topology in compounds 1 and 2, and all these octahedron topologies formed 1D polymeric chain through edge-sharing connecting modes. The flack values of 1 and 2 are 0.340(13) and 0.453(10), respectively. No chiral separation was done for both compounds.
2018, 34(2): 409-414
doi: 10.11862/CJIC.2018.045
Abstract:
Platinum nanoparticles were prepared via a potentiostatic electrodeposition method on a glassy carbon electrode from N, N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium tetrafluoroborate ([DEME] [BF4]) ionic liquid. At first, the effects of different deposition potentials and deposition times on the micromorphology of platinum nanoparticles were investigated. It has been found that the mean size of Pt nanoparticles obtained at -2.5 V for 480 s was estimated to be ca. 2.38 nm from the SEM and TEM images. Its face-centered cubic (fcc) crystal structure was confirmed by high-resolution transmission electron microscopy (HRTEM) and electron diffraction (SAED). At the same time, Platinum nanoparticles exposed significant (110) and (100) planes in sulfuric acid. Further study of the deposition behavior of platinum reveals that the diffusion process and the electrochemical process controll the two-step reduction of Pt(Ⅳ) together.
Platinum nanoparticles were prepared via a potentiostatic electrodeposition method on a glassy carbon electrode from N, N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium tetrafluoroborate ([DEME] [BF4]) ionic liquid. At first, the effects of different deposition potentials and deposition times on the micromorphology of platinum nanoparticles were investigated. It has been found that the mean size of Pt nanoparticles obtained at -2.5 V for 480 s was estimated to be ca. 2.38 nm from the SEM and TEM images. Its face-centered cubic (fcc) crystal structure was confirmed by high-resolution transmission electron microscopy (HRTEM) and electron diffraction (SAED). At the same time, Platinum nanoparticles exposed significant (110) and (100) planes in sulfuric acid. Further study of the deposition behavior of platinum reveals that the diffusion process and the electrochemical process controll the two-step reduction of Pt(Ⅳ) together.
