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2021 Volume 37 Issue 9
2021, 37(9): 1529-1535
doi: 10.11862/CJIC.2021.168
Abstract:
Five lanthanide metal complexes, [La2(BTO)3(H2O)8]·2H2O (1), [Ce2(BTO)3(H2O)8]·2H2O (2), [Pr2(BTO)3(H2O)8]·2H2O (3), [Sm2(BTO)3(H2O)8]·2H2O (4) and[Nd2(BTO)3(DMF)4]·6H2O (5), were synthesized by solvothermal method with 1H, 1'H-5, 5'-bitetrazole-1, 1'-diolate (H2BTO) as ligand and lanthanide metal ions as metal centers. The structures of five complexes were characterized by single crystal X-ray diffraction and elemental analysis. The results show that all the complexes belong to monoclinic system, P21/n space group. The thermal stability of complexes 1~4 was investigated by differential scanning calorimetry. And their kinetic parameters of thermal decomposition were calculated by Kissinger method and Ozawa method, respectively.
Five lanthanide metal complexes, [La2(BTO)3(H2O)8]·2H2O (1), [Ce2(BTO)3(H2O)8]·2H2O (2), [Pr2(BTO)3(H2O)8]·2H2O (3), [Sm2(BTO)3(H2O)8]·2H2O (4) and[Nd2(BTO)3(DMF)4]·6H2O (5), were synthesized by solvothermal method with 1H, 1'H-5, 5'-bitetrazole-1, 1'-diolate (H2BTO) as ligand and lanthanide metal ions as metal centers. The structures of five complexes were characterized by single crystal X-ray diffraction and elemental analysis. The results show that all the complexes belong to monoclinic system, P21/n space group. The thermal stability of complexes 1~4 was investigated by differential scanning calorimetry. And their kinetic parameters of thermal decomposition were calculated by Kissinger method and Ozawa method, respectively.
2021, 37(9): 1536-1546
doi: 10.11862/CJIC.2021.184
Abstract:
The two-state reaction mechanism of NH3 synthesis from N2 and H2 catalyzed by Ru are theoretical studied on the singlet, triplet and quintet potential energy surface, and the density functional theory (DFT) UB3LYP methods was used, which is a typical two-state reaction. We calculated spin-orbital coupling constant (Hsoc) and intersystem crossing probability (PISC) at minimum energy crossing point (MECP) respectively, for MECP1:Hsoc=508.34 cm-1, P2ISC=0.85; for MECP9:Hsoc=269.21 cm-1, P2ISC=0.27. We used energy span model to determine that turnover frequency (TOF)-determining transition state (TDTS) of the reaction is 3TS2-3 and TOF-determining intermediate (TDI) of the reaction is 3IM9.
The two-state reaction mechanism of NH3 synthesis from N2 and H2 catalyzed by Ru are theoretical studied on the singlet, triplet and quintet potential energy surface, and the density functional theory (DFT) UB3LYP methods was used, which is a typical two-state reaction. We calculated spin-orbital coupling constant (Hsoc) and intersystem crossing probability (PISC) at minimum energy crossing point (MECP) respectively, for MECP1:Hsoc=508.34 cm-1, P2ISC=0.85; for MECP9:Hsoc=269.21 cm-1, P2ISC=0.27. We used energy span model to determine that turnover frequency (TOF)-determining transition state (TDTS) of the reaction is 3TS2-3 and TOF-determining intermediate (TDI) of the reaction is 3IM9.
2021, 37(9): 1547-1554
doi: 10.11862/CJIC.2021.186
Abstract:
The copper(Ⅱ) and silver(Ⅰ) complexes[Cu(L)(Ac)2]2 (1), [Ag(L)(NO3)]·H2O (2) (L=N, N'-dimethyl-5-nitro-2, 2'-biimidazole) has been synthesized. X-ray crystallographic study was used to determine the crystallographic structure of complex 1, which exhibits a five-coordinated dimeric copper-acetato paddle-wheel geometry. Complex 2 was characterized by elemental analysis, UV-Vis, FT-IR, solid fluorescence spectra, thermogravimetric analysis, ESI-MS and conductivity analysis. The structure of complex 2 probably was a two-coordinated mononuclear structural unit of linear configuration. The binding property of L and complexes toward calf thymus DNA (ct-DNA) was figured out via electronic absorption, fluorescence spectra and viscosity measurements. Complex 1 revealed slightly stronger DNA binding capability than 2 and ligand. The antianaerobe activities of L and its complexes were tested by two-fold agar dilution method. The results showed that L displayed favorable activity of anti-anaerobic bacteria against Actinobacillus actinomycetem (ATCC 29523) selectively with minimum inhibitory concentrations of 0.625~1.25 μg·mL-1, even better than the classical anti-anaerobic drug metronidazole.
The copper(Ⅱ) and silver(Ⅰ) complexes[Cu(L)(Ac)2]2 (1), [Ag(L)(NO3)]·H2O (2) (L=N, N'-dimethyl-5-nitro-2, 2'-biimidazole) has been synthesized. X-ray crystallographic study was used to determine the crystallographic structure of complex 1, which exhibits a five-coordinated dimeric copper-acetato paddle-wheel geometry. Complex 2 was characterized by elemental analysis, UV-Vis, FT-IR, solid fluorescence spectra, thermogravimetric analysis, ESI-MS and conductivity analysis. The structure of complex 2 probably was a two-coordinated mononuclear structural unit of linear configuration. The binding property of L and complexes toward calf thymus DNA (ct-DNA) was figured out via electronic absorption, fluorescence spectra and viscosity measurements. Complex 1 revealed slightly stronger DNA binding capability than 2 and ligand. The antianaerobe activities of L and its complexes were tested by two-fold agar dilution method. The results showed that L displayed favorable activity of anti-anaerobic bacteria against Actinobacillus actinomycetem (ATCC 29523) selectively with minimum inhibitory concentrations of 0.625~1.25 μg·mL-1, even better than the classical anti-anaerobic drug metronidazole.
2021, 37(9): 1555-1562
doi: 10.11862/CJIC.2021.181
Abstract:
Poly (ethylene glycol diamine) (NH2-PEG-NH2) modified graphene quantum dots (GODs) were conjugated with diethylenetriaminepentaacetic acid (DTPA) via an amide bond. Then the product further coordinated with Gd3+ ions, followed by the subsequent linkage of folic acid (FA) to form FA/GODs-Gd(DTPA). Next, an anticancer drug, doxorubicin (DOX), was loaded on the surface of FA/GODs-Gd(DTPA) to obtain the final fluorescence/MRI dual targeted imaging diagnostic reagents (FA/GODs-Gd(DTPA)/DOX) for lung cancer cells. The sample was characterized by transmission electron microscopy, UV-Vis absorption spectroscopy, fluorescence spectroscopy, laser confocal microscopy, and so on. Compared with normal HLF cells, the results of MRI, confocal laser scanning microscopy and MTT showed that the prepared FA/GODs-Gd(DTPA)/DOX could be targeted to detect lung cancer H460 cells, in which folate receptor was highly expressed, and also displayed significant anti-tumor activity.
Poly (ethylene glycol diamine) (NH2-PEG-NH2) modified graphene quantum dots (GODs) were conjugated with diethylenetriaminepentaacetic acid (DTPA) via an amide bond. Then the product further coordinated with Gd3+ ions, followed by the subsequent linkage of folic acid (FA) to form FA/GODs-Gd(DTPA). Next, an anticancer drug, doxorubicin (DOX), was loaded on the surface of FA/GODs-Gd(DTPA) to obtain the final fluorescence/MRI dual targeted imaging diagnostic reagents (FA/GODs-Gd(DTPA)/DOX) for lung cancer cells. The sample was characterized by transmission electron microscopy, UV-Vis absorption spectroscopy, fluorescence spectroscopy, laser confocal microscopy, and so on. Compared with normal HLF cells, the results of MRI, confocal laser scanning microscopy and MTT showed that the prepared FA/GODs-Gd(DTPA)/DOX could be targeted to detect lung cancer H460 cells, in which folate receptor was highly expressed, and also displayed significant anti-tumor activity.
2021, 37(9): 1563-1570
doi: 10.11862/CJIC.2021.191
Abstract:
The effect of treatment temperature on the specific surface area, morphology, particle size and metal content of spherical Ni0.65Co0.10Mn0.25(OH)2 precursors were systematically studied. X-ray diffraction, thermogravimetric, X-ray photoelectron spectroscopy were used to reveal the phase evolution behavior, thermal stability of the precursor and the valence state change of transition metal elements during high temperature treatment.
The effect of treatment temperature on the specific surface area, morphology, particle size and metal content of spherical Ni0.65Co0.10Mn0.25(OH)2 precursors were systematically studied. X-ray diffraction, thermogravimetric, X-ray photoelectron spectroscopy were used to reveal the phase evolution behavior, thermal stability of the precursor and the valence state change of transition metal elements during high temperature treatment.
2021, 37(9): 1571-1578
doi: 10.11862/CJIC.2021.187
Abstract:
Firstly, 1D TiO2 nanobelts were uniformly interspersed into 3D ZnIn2S4 microspheres assembled by lamellar structure by solvothermal method. The heterostructure photocatalyst can effectively suppress the re-combination of photoinduced electron-hole pairs. Secondly, 0D Ag nanoparticles were loaded onto 3D ZnIn2S4/1D TiO2 hetero-structure by photodeposition method. Owing to the plasma effect of 0D Ag nanoparticles and the action of electron co -catalyst, ternary 3D ZnIn2S4/1D TiO2/0D Ag composite photocatalyst showed excellent performance in photocatalytic hydrogen evolution. Under simulated sunlight irradiation, the hydrogen production rate of ZnIn2S4/TiO2/Ag composite photocatalyst reached 715 μmol·g-1·h-1, which was 2.7 times, 3.3 times, 3.8 times, 184 times and 518 times higher than those of ZnIn2S4/TiO2, ZnIn2S4/P25, TiO2 and P25, respectively. At the same time, by means of X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and UV-Vis diffuse reflection spectroscopy, the excellent performance of the composite catalyst was further demonstrated.
Firstly, 1D TiO2 nanobelts were uniformly interspersed into 3D ZnIn2S4 microspheres assembled by lamellar structure by solvothermal method. The heterostructure photocatalyst can effectively suppress the re-combination of photoinduced electron-hole pairs. Secondly, 0D Ag nanoparticles were loaded onto 3D ZnIn2S4/1D TiO2 hetero-structure by photodeposition method. Owing to the plasma effect of 0D Ag nanoparticles and the action of electron co -catalyst, ternary 3D ZnIn2S4/1D TiO2/0D Ag composite photocatalyst showed excellent performance in photocatalytic hydrogen evolution. Under simulated sunlight irradiation, the hydrogen production rate of ZnIn2S4/TiO2/Ag composite photocatalyst reached 715 μmol·g-1·h-1, which was 2.7 times, 3.3 times, 3.8 times, 184 times and 518 times higher than those of ZnIn2S4/TiO2, ZnIn2S4/P25, TiO2 and P25, respectively. At the same time, by means of X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and UV-Vis diffuse reflection spectroscopy, the excellent performance of the composite catalyst was further demonstrated.
2021, 37(9): 1579-1588
doi: 10.11862/CJIC.2021.180
Abstract:
Co-Co9S8/N-KB composite catalyst supported by high conductivity carbon (nitrogen doped Ketjen black) and introduced by single metal for oxygen reduction reaction (ORR) was prepared using Prussian blue analogue as precursor through high temperature annealing technology. By comparison of different annealing temperatures, it is found that the catalyst gained at the annealing temperature of 800℃ showed the best catalytic activity for ORR. The initial potential and half-wave potential were 0.93 and 0.83 V respectively, comparable to commercial Pt/C, and the limit current density reached 5.7 mA·cm-2, higher than that of Pt/C. After a long period of 10 000 s for chronoam-perometry experiment, the current density still retained at 95.6% of the initial, and the half-wave potential shifted just only 8.6 mV after 5 000 cycles subjected in a range of 0.5 to 1.0 V (vs RHE) during the accelerated durability test. In addition, in actual Al-air full battery applications, the discharge platform of Co-Co9S8/N-KB reached 1.53 V at a discharge density of 50 mA·cm-2, higher than that of Pt/C.
Co-Co9S8/N-KB composite catalyst supported by high conductivity carbon (nitrogen doped Ketjen black) and introduced by single metal for oxygen reduction reaction (ORR) was prepared using Prussian blue analogue as precursor through high temperature annealing technology. By comparison of different annealing temperatures, it is found that the catalyst gained at the annealing temperature of 800℃ showed the best catalytic activity for ORR. The initial potential and half-wave potential were 0.93 and 0.83 V respectively, comparable to commercial Pt/C, and the limit current density reached 5.7 mA·cm-2, higher than that of Pt/C. After a long period of 10 000 s for chronoam-perometry experiment, the current density still retained at 95.6% of the initial, and the half-wave potential shifted just only 8.6 mV after 5 000 cycles subjected in a range of 0.5 to 1.0 V (vs RHE) during the accelerated durability test. In addition, in actual Al-air full battery applications, the discharge platform of Co-Co9S8/N-KB reached 1.53 V at a discharge density of 50 mA·cm-2, higher than that of Pt/C.
2021, 37(9): 1589-1596
doi: 10.11862/CJIC.2021.197
Abstract:
The molten salt electrolysis method and transition metal Cu-doping were used to prepare two different of nanostructured Cu/MoS2. Two kinds of Cu/MoS2 working electrodes were prepared by coating method. X-ray diffraction, transmission electron microscope, energy dispersive X-ray spectroscopy, scanning electron microscope, selected area electron diffraction and various electrochemical methods were used to study the structure and performance. The results showed that Cu/MoS2 nanosheets exhibited excellent hydrogen evolution reaction catalytic performance in alkaline solution (1 mol·L-1 KOH): when the current density was 10 mA·cm-2, the overpotential was 199.6 mV, and the Tafel slope was 59 mV·dec-1, double layer capacitor was 26.1 mF·cm-2, equivalent charge transfer resistance was 12.4 Ω, and showed relatively good electrochemical durability and stability.
The molten salt electrolysis method and transition metal Cu-doping were used to prepare two different of nanostructured Cu/MoS2. Two kinds of Cu/MoS2 working electrodes were prepared by coating method. X-ray diffraction, transmission electron microscope, energy dispersive X-ray spectroscopy, scanning electron microscope, selected area electron diffraction and various electrochemical methods were used to study the structure and performance. The results showed that Cu/MoS2 nanosheets exhibited excellent hydrogen evolution reaction catalytic performance in alkaline solution (1 mol·L-1 KOH): when the current density was 10 mA·cm-2, the overpotential was 199.6 mV, and the Tafel slope was 59 mV·dec-1, double layer capacitor was 26.1 mF·cm-2, equivalent charge transfer resistance was 12.4 Ω, and showed relatively good electrochemical durability and stability.
2021, 37(9): 1597-1605
doi: 10.11862/CJIC.2021.188
Abstract:
A series of macrocyclic arenes derived phenanthrolines have been designed and synthesized, which could form a series of novel heteroleptic copper photosensitizers CuPS 1~CuPS 6 with Xantphos as phosphorus ligands. The photosensitive activity of CuPS 1~CuPS 6 was studied in homogeneous photocatalytic water reduction system for hydrogen production. The research results showed that 1-naphthyl was the preferred substituent and the turnover number (TON) of CuPS 3 for hydrogen production was up to 957. Through theoretical calculation and comparative analysis, a larger dihedral angle of the 1-naphthyl substituent and the phenanthroline nucleus has a better steric effect to protect the excited state of the copper complex. Thus, CuPS 3 displayed a higher fluorescence quantum yield (0.036) and a longer excited state lifetime (1.36 μs).
A series of macrocyclic arenes derived phenanthrolines have been designed and synthesized, which could form a series of novel heteroleptic copper photosensitizers CuPS 1~CuPS 6 with Xantphos as phosphorus ligands. The photosensitive activity of CuPS 1~CuPS 6 was studied in homogeneous photocatalytic water reduction system for hydrogen production. The research results showed that 1-naphthyl was the preferred substituent and the turnover number (TON) of CuPS 3 for hydrogen production was up to 957. Through theoretical calculation and comparative analysis, a larger dihedral angle of the 1-naphthyl substituent and the phenanthroline nucleus has a better steric effect to protect the excited state of the copper complex. Thus, CuPS 3 displayed a higher fluorescence quantum yield (0.036) and a longer excited state lifetime (1.36 μs).
2021, 37(9): 1606-1612
doi: 10.11862/CJIC.2021.176
Abstract:
Mesoporous carbon (MC), carbon nanotube (CNT) and MC-CNT binary counter electrodes prepared with different MC/CNT weight ratios (mMC/mCNT) were first studied on the power conversion efficiencies (PCE). Further, CuS nanomaterials pre-prepared through hydrothermal method were added into, and then MC-CNT-CuS ternary counter electrodes were synthesized. The influence of CuS content as well as film thickness on the efficiency was also probed. The experimental results showed that when mMC/mCNT=3/2, the synergistic effect of the two carbon materials reached the maximum, resulting in the highest PCE of 12.69% for the binary MC-CNT counter electrode. The PCE after incorporation of 0.4 g CuS was improved to the highest value of 13.18% when the counter electrode was screen printed five times.
Mesoporous carbon (MC), carbon nanotube (CNT) and MC-CNT binary counter electrodes prepared with different MC/CNT weight ratios (mMC/mCNT) were first studied on the power conversion efficiencies (PCE). Further, CuS nanomaterials pre-prepared through hydrothermal method were added into, and then MC-CNT-CuS ternary counter electrodes were synthesized. The influence of CuS content as well as film thickness on the efficiency was also probed. The experimental results showed that when mMC/mCNT=3/2, the synergistic effect of the two carbon materials reached the maximum, resulting in the highest PCE of 12.69% for the binary MC-CNT counter electrode. The PCE after incorporation of 0.4 g CuS was improved to the highest value of 13.18% when the counter electrode was screen printed five times.
2021, 37(9): 1613-1624
doi: 10.11862/CJIC.2021.192
Abstract:
NaP1 zeolite were synthesized by calcination-hydrothermal method using rice husk as the silicon source. The effects of different silicon-to-aluminum molar ratio (nSiO2/nAl2O3), water-to-sodium molar ratio (nH2O/nNa2O), crystallization temperature and crystallization time on the crystallinity of zeolite were investigated. The alkane isomerization catalyst of x%Ni/NaP1 (x% was the mass ratio of Ni to NaP1) was prepared with the NaP1 zeolite as the support. Xray powder diffraction, infrared spectroscopy, scanning electron microscope, transmission electron microscope-Xray energy spectrum, N2 adsorption-desorption, X-ray photoelectron energy spectrum, NH3 temperature programmed desorption and differential thermal analysis characterization methods were used to analyze the crystal structure, microscopic morphology and metal dispersion of the synthesized materials, and the effect of nickel loading on the acidity and thermal stability of NaP1 were studied. The results showed that the optimal synthesis conditions for NaP1 zeolite prepared from rice husk as silicon source were as follows: nH2O/nNa2O=35, nSiO2/nAl2O3=10, crystallization temperature was 95℃, and the crystallization time was 12 h. Under these synthesizing conditions, the crystallinity of NaP1 crystal was 99.38%. In the experiment of n-heptane isomerization as a probe, 4%Ni/NaP1 had the best catalytic performance at a reduction temperature of 400℃, reduction time of 4 h, weight hourly space velocity of 3.52 h-1, and reaction temperature of 320℃, and the maximum yield was 46.41%, with the conversion of n-heptane and selectivity of iso-heptane of 65.49% and 70.86%, respectively.
NaP1 zeolite were synthesized by calcination-hydrothermal method using rice husk as the silicon source. The effects of different silicon-to-aluminum molar ratio (nSiO2/nAl2O3), water-to-sodium molar ratio (nH2O/nNa2O), crystallization temperature and crystallization time on the crystallinity of zeolite were investigated. The alkane isomerization catalyst of x%Ni/NaP1 (x% was the mass ratio of Ni to NaP1) was prepared with the NaP1 zeolite as the support. Xray powder diffraction, infrared spectroscopy, scanning electron microscope, transmission electron microscope-Xray energy spectrum, N2 adsorption-desorption, X-ray photoelectron energy spectrum, NH3 temperature programmed desorption and differential thermal analysis characterization methods were used to analyze the crystal structure, microscopic morphology and metal dispersion of the synthesized materials, and the effect of nickel loading on the acidity and thermal stability of NaP1 were studied. The results showed that the optimal synthesis conditions for NaP1 zeolite prepared from rice husk as silicon source were as follows: nH2O/nNa2O=35, nSiO2/nAl2O3=10, crystallization temperature was 95℃, and the crystallization time was 12 h. Under these synthesizing conditions, the crystallinity of NaP1 crystal was 99.38%. In the experiment of n-heptane isomerization as a probe, 4%Ni/NaP1 had the best catalytic performance at a reduction temperature of 400℃, reduction time of 4 h, weight hourly space velocity of 3.52 h-1, and reaction temperature of 320℃, and the maximum yield was 46.41%, with the conversion of n-heptane and selectivity of iso-heptane of 65.49% and 70.86%, respectively.
2021, 37(9): 1625-1632
doi: 10.11862/CJIC.2021.185
Abstract:
Pd/H-ZSM-5 catalysts were prepared by conventional impregnation method with commercial hierarchical NH4-ZSM-5 and H-ZSM-5 (NH4-ZSM-5 calcined at 550℃ for 6 h in air atmosphere) zeolite as the supports, and H2PdCl4 as the metal precursor. The physicochemical properties and catalytic performance of the prepared samples were characterized by X-ray diffraction, scanning electron microscopy, N2 adsorption-desorption, UV-Vis spectroscopy, X-ray photoelectron spectroscopy, NH3-temperature programmed desorption, transmission electron microscopy and naphthalene hydrogenation reaction. The results showed that the coordination cations over zeolites greatly influence the dispersion of the supported metal species and catalyst acidity. The NH4+ over ZSM-5 supports was conducive to the dispersion of the supported Pd species, and the prepared Pd/H-ZSM-5(NH4) had more acid sites than Pd/H-ZSM-5(H), which resulted in that Pd/H-ZSM-5(NH4) exhibited higher catalytic activity in naphthalene hydrogenation than Pd/H-ZSM-5(H).
Pd/H-ZSM-5 catalysts were prepared by conventional impregnation method with commercial hierarchical NH4-ZSM-5 and H-ZSM-5 (NH4-ZSM-5 calcined at 550℃ for 6 h in air atmosphere) zeolite as the supports, and H2PdCl4 as the metal precursor. The physicochemical properties and catalytic performance of the prepared samples were characterized by X-ray diffraction, scanning electron microscopy, N2 adsorption-desorption, UV-Vis spectroscopy, X-ray photoelectron spectroscopy, NH3-temperature programmed desorption, transmission electron microscopy and naphthalene hydrogenation reaction. The results showed that the coordination cations over zeolites greatly influence the dispersion of the supported metal species and catalyst acidity. The NH4+ over ZSM-5 supports was conducive to the dispersion of the supported Pd species, and the prepared Pd/H-ZSM-5(NH4) had more acid sites than Pd/H-ZSM-5(H), which resulted in that Pd/H-ZSM-5(NH4) exhibited higher catalytic activity in naphthalene hydrogenation than Pd/H-ZSM-5(H).
2021, 37(9): 1633-1641
doi: 10.11862/CJIC.2021.194
Abstract:
Ni nanospheres and Ni@Co(OH)2 nano-urchin-spheres precursor were successively fabricated with hydrothermal technique, and then the latter were changed into NiO@CoO by high temperature calcination process, and Ni2P@CoP3 core-shell nanospheres were finally obtained using sodium hypophoshpite as raw material by high temperature phosphating process. The morphologies, structures and compositions of the as-obtained products were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), high angle annular dark field-scanning transmission electron microscope (HAADF-STEM), X-ray powder diffractometer (XRD), energy dispersive spectrometer (EDS) and X-ray photoelectron spectroscopy (XPS). At the same time, the electrochemical performance of the electrodes were investigated by cyclic voltammetry (CV), galvanostatic charge/discharge (GCD) and cycling stability experiments. The results showed that as-obtained Ni2P@CoP3 core-shell nanospheres with diameter of~400 nm were composed of hexagonal Ni2P nanocore and cubic CoP3 nanoshell. Compared with pure Ni2P or CoP3 nanospheres, Ni2P@CoP3 core-shell nanospheres are more conducive to the mass transfer of electrolyte and promote the pseudo capacitive reaction because of its synergistic effect of composite structure, which shows higher specific capacity, stability and longer cycle life.
Ni nanospheres and Ni@Co(OH)2 nano-urchin-spheres precursor were successively fabricated with hydrothermal technique, and then the latter were changed into NiO@CoO by high temperature calcination process, and Ni2P@CoP3 core-shell nanospheres were finally obtained using sodium hypophoshpite as raw material by high temperature phosphating process. The morphologies, structures and compositions of the as-obtained products were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), high angle annular dark field-scanning transmission electron microscope (HAADF-STEM), X-ray powder diffractometer (XRD), energy dispersive spectrometer (EDS) and X-ray photoelectron spectroscopy (XPS). At the same time, the electrochemical performance of the electrodes were investigated by cyclic voltammetry (CV), galvanostatic charge/discharge (GCD) and cycling stability experiments. The results showed that as-obtained Ni2P@CoP3 core-shell nanospheres with diameter of~400 nm were composed of hexagonal Ni2P nanocore and cubic CoP3 nanoshell. Compared with pure Ni2P or CoP3 nanospheres, Ni2P@CoP3 core-shell nanospheres are more conducive to the mass transfer of electrolyte and promote the pseudo capacitive reaction because of its synergistic effect of composite structure, which shows higher specific capacity, stability and longer cycle life.
2021, 37(9): 1642-1648
doi: 10.11862/CJIC.2021.125
Abstract:
Copper ions can be coordinated into porphyrin ligands of PCN-222 directly to form PCN-222-Cu, which is first used for lithium-sulfur batteries in this study. The crystal structure, morphology and electrochemical properties were characterized systematically by ultraviolet-visible (UV-Vis) spectra, powder X-ray diffraction (PXRD), N2 adsorption-desorption test, scanning electron microscope (SEM), cyclic voltammetry (CV) and galvanostatic charge-discharge test. UV-Vis spectra indicate Cu2+ was successfully coordinated into the porphyrin. The electrochemical test results showed that the reversible specific capacity of S-in-PCN-222-Cu electrodes could maintain 840 mAh·g-1 after 300 cycles at 1C. When the rate was increased to 3C, S-in-PCN-222-Cu electrode could still maintain a high reversible specific capacity of 430 mAh·g-1 after 800 cycles, and the capacity decay rate was only 0.042% per cycle, which was much better than that of S-in-PCN-222 electrode. This result indicates that the synergistic effect of Cu2+ and N atoms in the porphyrin rings can effectively decrease the electrochemical polarization, thus significantly improve the electrochemical performance and cycling stability of the porphyrin-based metal-organic framework as sulfur hosts.
Copper ions can be coordinated into porphyrin ligands of PCN-222 directly to form PCN-222-Cu, which is first used for lithium-sulfur batteries in this study. The crystal structure, morphology and electrochemical properties were characterized systematically by ultraviolet-visible (UV-Vis) spectra, powder X-ray diffraction (PXRD), N2 adsorption-desorption test, scanning electron microscope (SEM), cyclic voltammetry (CV) and galvanostatic charge-discharge test. UV-Vis spectra indicate Cu2+ was successfully coordinated into the porphyrin. The electrochemical test results showed that the reversible specific capacity of S-in-PCN-222-Cu electrodes could maintain 840 mAh·g-1 after 300 cycles at 1C. When the rate was increased to 3C, S-in-PCN-222-Cu electrode could still maintain a high reversible specific capacity of 430 mAh·g-1 after 800 cycles, and the capacity decay rate was only 0.042% per cycle, which was much better than that of S-in-PCN-222 electrode. This result indicates that the synergistic effect of Cu2+ and N atoms in the porphyrin rings can effectively decrease the electrochemical polarization, thus significantly improve the electrochemical performance and cycling stability of the porphyrin-based metal-organic framework as sulfur hosts.
2021, 37(9): 1649-1658
doi: 10.11862/CJIC.2021.196
Abstract:
Here, nickel cobalt hydroxide (Ni0.928Co0.072(OH)2) and aluminum isopropanol (C9H21AlO3) were used as raw material. The ternary precursor was synthesized by aluminum isopropanol hydrolysis. Then, the cathode material LiNi0.88Co0.07Al0.05O2 was obtained by mixing Ni0.928Co0.072(OH)2 with lithium salt and subsequent sintering. After washing and re-sintering, the crystal structure, microstructure and electrochemical properties of the target products were characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectronic spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS), transmission electron microscope (TEM) and electrochemical tests. The results showed that synthesized LiNi0.88Co0.07Al0.05O2 had better comprehensive electrochemical performance when the ratio of solid to liquid was 1:25, washed with deionized water for three times and calcined at 600℃ for 2 h. The specific discharge capacity of 0.2C was up to 207.6 mAh·g-1, the first charge and discharge efficiency was 84.8%, and the specific discharge capacity of 1C was 192.0 mAh·g-1. After 100 cycles, the specific discharge capacity of the material was still 148.0 mAh·g-1, and the capacity retention rate reached 77.1%.
Here, nickel cobalt hydroxide (Ni0.928Co0.072(OH)2) and aluminum isopropanol (C9H21AlO3) were used as raw material. The ternary precursor was synthesized by aluminum isopropanol hydrolysis. Then, the cathode material LiNi0.88Co0.07Al0.05O2 was obtained by mixing Ni0.928Co0.072(OH)2 with lithium salt and subsequent sintering. After washing and re-sintering, the crystal structure, microstructure and electrochemical properties of the target products were characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectronic spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS), transmission electron microscope (TEM) and electrochemical tests. The results showed that synthesized LiNi0.88Co0.07Al0.05O2 had better comprehensive electrochemical performance when the ratio of solid to liquid was 1:25, washed with deionized water for three times and calcined at 600℃ for 2 h. The specific discharge capacity of 0.2C was up to 207.6 mAh·g-1, the first charge and discharge efficiency was 84.8%, and the specific discharge capacity of 1C was 192.0 mAh·g-1. After 100 cycles, the specific discharge capacity of the material was still 148.0 mAh·g-1, and the capacity retention rate reached 77.1%.
2021, 37(9): 1665-1673
doi: 10.11862/CJIC.2021.183
Abstract:
A functional ferrocenyl ligand (L) with D-A configuration and its complex (NHEt3)[ZnL3] were synthesized. Single crystal analysis shows that the ferrocene diketone loses a proton to coordinate with Zn2+, which finally gives the negative monovalent ferrocene diketo Zn(Ⅱ) complex. The results from electrochemical cyclic voltammetry and IR in situ revealed that (NHEt3)[Zn(L)3] went through two-step oxidation and one-step reduction process. As the potential increased during the oxidation process, one ferrocene (Fc) unit was oxidized to Fc+, forming a D-A asymmetric structure mode. Along with the oxidation continued, the other Fc units were also oxidized. The three Fc+ with Zn2+ still formed the D-A structure mode, and finally the Fc+ was reduced to Fc in one step. Theoretical calculation result shows that the complex is prone to exist high degree of electron delocalization. The experiment results from nonlinear optical property determinations show that the complex has a larger two/three-photon absorption cross sections and third-order nonlinear optical susceptibility in near IR region.
A functional ferrocenyl ligand (L) with D-A configuration and its complex (NHEt3)[ZnL3] were synthesized. Single crystal analysis shows that the ferrocene diketone loses a proton to coordinate with Zn2+, which finally gives the negative monovalent ferrocene diketo Zn(Ⅱ) complex. The results from electrochemical cyclic voltammetry and IR in situ revealed that (NHEt3)[Zn(L)3] went through two-step oxidation and one-step reduction process. As the potential increased during the oxidation process, one ferrocene (Fc) unit was oxidized to Fc+, forming a D-A asymmetric structure mode. Along with the oxidation continued, the other Fc units were also oxidized. The three Fc+ with Zn2+ still formed the D-A structure mode, and finally the Fc+ was reduced to Fc in one step. Theoretical calculation result shows that the complex is prone to exist high degree of electron delocalization. The experiment results from nonlinear optical property determinations show that the complex has a larger two/three-photon absorption cross sections and third-order nonlinear optical susceptibility in near IR region.
2021, 37(9): 1674-1682
doi: 10.11862/CJIC.2021.178
Abstract:
The first-principles method based on density functional theory was performed to investigate the electronic structure and optical properties of the armchair nanoribbons (AC-g-C3N4NRs) and zigzag g-C3N4 nanoribbons (ZZ-g-C3N4Rs). The results show that the edge H atoms of AC-g-C3N4NRs and ZZ-g-C3N4NRs can exist stably. The valence band maximums (VBMs) of AC-g-C3N4NRs are mainly contributed by most of N atoms, whereas the VBMs of ZZ-g-C3N4NRs are contributed by the N atoms near the CH edge. The conduction band minimums (CBMs) of AC-g-C3N4Rs mainly belong to C and N atoms near the one edge or two edges of AC-g-C3N4NRs, while the CBMs of ZZ-g-C3N4Rs mainly belong to C and N atoms near the NH edge of ZZ-g-C3N4NRs. The absorption coefficient and the reflectivity of AC-g-C3N4NR or ZZ-g-C3N4NR increased with the increasing width of the corresponding nanoribbon. An obvious blueshift phenomenon of the absorption coefficient could be generated in the low-energy range as the width of AC-g-C3N4NR increased.
The first-principles method based on density functional theory was performed to investigate the electronic structure and optical properties of the armchair nanoribbons (AC-g-C3N4NRs) and zigzag g-C3N4 nanoribbons (ZZ-g-C3N4Rs). The results show that the edge H atoms of AC-g-C3N4NRs and ZZ-g-C3N4NRs can exist stably. The valence band maximums (VBMs) of AC-g-C3N4NRs are mainly contributed by most of N atoms, whereas the VBMs of ZZ-g-C3N4NRs are contributed by the N atoms near the CH edge. The conduction band minimums (CBMs) of AC-g-C3N4Rs mainly belong to C and N atoms near the one edge or two edges of AC-g-C3N4NRs, while the CBMs of ZZ-g-C3N4Rs mainly belong to C and N atoms near the NH edge of ZZ-g-C3N4NRs. The absorption coefficient and the reflectivity of AC-g-C3N4NR or ZZ-g-C3N4NR increased with the increasing width of the corresponding nanoribbon. An obvious blueshift phenomenon of the absorption coefficient could be generated in the low-energy range as the width of AC-g-C3N4NR increased.
2021, 37(9): 1683-1690
doi: 10.11862/CJIC.2021.195
Abstract:
SiO2@CdTe@Au nanocomposites were prepared by using SiO2 nanoparticles, CdTe quantum dots and Au nanoparticles as raw materials by layer-by-layer adsorption. The samples were tested and characterized to show the successful preparation of nanocomposites. The Z-scan technique was used to measure the nonlinear absorption optical properties of SiO2@CdTe and SiO2@CdTe@Au nanocomposite samples under nanosecond laser pulses. The analysis of the experimental results showed that SiO2@CdTe and SiO2@CdTe@Au nanocomposites all exhibited saturated absorption properties. SiO2@CdTe@Au nanocomposite presented enhanced nonlinear optical characteristics compared to SiO2@CdTe nanocomposite, and the mechanism was analyzed.
SiO2@CdTe@Au nanocomposites were prepared by using SiO2 nanoparticles, CdTe quantum dots and Au nanoparticles as raw materials by layer-by-layer adsorption. The samples were tested and characterized to show the successful preparation of nanocomposites. The Z-scan technique was used to measure the nonlinear absorption optical properties of SiO2@CdTe and SiO2@CdTe@Au nanocomposite samples under nanosecond laser pulses. The analysis of the experimental results showed that SiO2@CdTe and SiO2@CdTe@Au nanocomposites all exhibited saturated absorption properties. SiO2@CdTe@Au nanocomposite presented enhanced nonlinear optical characteristics compared to SiO2@CdTe nanocomposite, and the mechanism was analyzed.
2021, 37(9): 1691-1699
doi: 10.11862/CJIC.2021.193
Abstract:
A Nd3+ MOF, namely {[Nd(bpt)(DMF)(H2O)]·2H2O}n (1) (H3bpt=biphenyl-3, 4', 5-tricarboxylic acid, DMF=N, N-dimethylformamide), has been obtained by the self-assemble reaction of NdCl3·6H2O and H3bpt ligand under solvothermal conditions (DMF/H2O). Complex 1 was characterized by means of elemental analysis, infrared spectroscopy, powder X-ray diffraction and single-crystal X-ray diffraction analyses. Single-crystal X-ray structural analysis reveals that complex 1 displays three-dimensional frameworks featuring a (5, 5)-connected topological network with the point symbol of 44·63·83)(48 62). In addition, the thermal stability, luminescent properties, photocatalytic behaviour, and magnetic property of complex 1 were also investigated in detail in the solid state.
A Nd3+ MOF, namely {[Nd(bpt)(DMF)(H2O)]·2H2O}n (1) (H3bpt=biphenyl-3, 4', 5-tricarboxylic acid, DMF=N, N-dimethylformamide), has been obtained by the self-assemble reaction of NdCl3·6H2O and H3bpt ligand under solvothermal conditions (DMF/H2O). Complex 1 was characterized by means of elemental analysis, infrared spectroscopy, powder X-ray diffraction and single-crystal X-ray diffraction analyses. Single-crystal X-ray structural analysis reveals that complex 1 displays three-dimensional frameworks featuring a (5, 5)-connected topological network with the point symbol of 44·63·83)(48 62). In addition, the thermal stability, luminescent properties, photocatalytic behaviour, and magnetic property of complex 1 were also investigated in detail in the solid state.
2021, 37(9): 1700-1706
doi: 10.11862/CJIC.2021.189
Abstract:
Zn-doped block-shaped monoclinic WO3 composite (Zn-doped WO3) was synthesized via a facile method and the photocatalytic activity of rhodamine B (RhB) over Zn-doped WO3 was evaluated. The prepared samples were characterized by X-ray diffraction, Raman spectrum, scanning electron micrograph, UV-Vis diffuse reflection spectrum, Fourier transform infrared spectrum, and X-ray photoelectron spectrum and other techniques, and the results showed that the block-shaped monoclinic WO3 did not be changed by appropriate amount of Zn doping. The photo-catalytic results illustrated that mass ratio of 5% Zn doped WO3 performed the best photocatalytic efficiency due to the formation of more oxygen vacancy and the increase of hydroxyl groups number.
Zn-doped block-shaped monoclinic WO3 composite (Zn-doped WO3) was synthesized via a facile method and the photocatalytic activity of rhodamine B (RhB) over Zn-doped WO3 was evaluated. The prepared samples were characterized by X-ray diffraction, Raman spectrum, scanning electron micrograph, UV-Vis diffuse reflection spectrum, Fourier transform infrared spectrum, and X-ray photoelectron spectrum and other techniques, and the results showed that the block-shaped monoclinic WO3 did not be changed by appropriate amount of Zn doping. The photo-catalytic results illustrated that mass ratio of 5% Zn doped WO3 performed the best photocatalytic efficiency due to the formation of more oxygen vacancy and the increase of hydroxyl groups number.
2021, 37(9): 1707-1712
doi: 10.11862/CJIC.2021.190
Abstract:
Two new mononuclear Cu(Ⅱ) complexes, trans-[Cu(L1)2(NO3)2]0.5[Cu(L1)2(H2O)2]0.5(NO3) (1) and trans-[Cu(L2)2(NO3)2]0.5[Cu(L2)2(H2O)2]0.5(NO3)·2CH3OH (2) (L1=3-(2-pyridyl)-4-phenyl-5-(2-furanyl)-1, 2, 4-triazole, L2=3-(2-pyridyl) -4-(p-fluorophenyl)-5-(2-furanyl)-1, 2, 4-triazole), were synthesized and characterized by FT-IR, elemental analyses, thermogravimetric analyses, single-crystal X-ray crystallography and powder X-ray diffraction. Both complexes 1 and 2 crystallize in triclinic system with space group P1. The crystal structure analysis shows that there are two crys-tallographically different Cu(Ⅱ) ions in 1 and 2 and each Cu(Ⅱ) ion lies in a distorted octahedral[CuN4O2] environment. However, in the axial position one Cu(Ⅱ) ion is coordinated with two water molecules, while another Cu(Ⅱ) ion with two nitrate ions. The L1 or L2 ligand coordinates with Cu(Ⅱ) via one pyridine N atom and one triazole N atom, while the furanyl group does not participate in coordination. In 1 and 2 there are some intermolecular C-H…N, C-H…O, O-H…O hydrogen bonding and C-H…π interactions, linking the mononuclear complex (1 or 2) to form a two-dimensional network.
Two new mononuclear Cu(Ⅱ) complexes, trans-[Cu(L1)2(NO3)2]0.5[Cu(L1)2(H2O)2]0.5(NO3) (1) and trans-[Cu(L2)2(NO3)2]0.5[Cu(L2)2(H2O)2]0.5(NO3)·2CH3OH (2) (L1=3-(2-pyridyl)-4-phenyl-5-(2-furanyl)-1, 2, 4-triazole, L2=3-(2-pyridyl) -4-(p-fluorophenyl)-5-(2-furanyl)-1, 2, 4-triazole), were synthesized and characterized by FT-IR, elemental analyses, thermogravimetric analyses, single-crystal X-ray crystallography and powder X-ray diffraction. Both complexes 1 and 2 crystallize in triclinic system with space group P1. The crystal structure analysis shows that there are two crys-tallographically different Cu(Ⅱ) ions in 1 and 2 and each Cu(Ⅱ) ion lies in a distorted octahedral[CuN4O2] environment. However, in the axial position one Cu(Ⅱ) ion is coordinated with two water molecules, while another Cu(Ⅱ) ion with two nitrate ions. The L1 or L2 ligand coordinates with Cu(Ⅱ) via one pyridine N atom and one triazole N atom, while the furanyl group does not participate in coordination. In 1 and 2 there are some intermolecular C-H…N, C-H…O, O-H…O hydrogen bonding and C-H…π interactions, linking the mononuclear complex (1 or 2) to form a two-dimensional network.
