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2021 Volume 40 Issue 1
2021, 40(1): 7-22
doi: 10.14102/j.cnki.0254-5861.2011-2752
Abstract:
Photocatalytic hydrogen generation from water-splitting holds huge promise for resolving the current energy shortage and environmental issues. Nevertheless, it is still challenging so far to develop non-noble-metal photocatalysts which are efficient toward solar-powered hydrogen evolution reaction (HER). In this work, through an ultrasonic water-bath strategy combined with solvothermal and electrostatic assembly processes, we obtain homogeneous Cd1-xZnxS–Ni2P–MoS2 hybrid nano-spheres consisting of Cd1-xZnxS solid solutions decorated by Ni2P and 1T/2H MoS2 cocatalysts, which demonstrate excellent activity and stability for visible-light-responsive (λ > 420 nm) H2 production. Specifically, the Cd1-xZnxS–Ni2P–MoS2 nano-spheres with 2 wt% Ni2P and 0.2 wt% MoS2 (CZ0.7S–2N–0.2M) exhibit the optimal HER activity of 55.77 mmol∙g-1∙h-1, about 47 and 32 times more than that of CZ0.7S and Pt–CZ0.7S, respectively. The outstanding HER performance of Cd1-xZnxS–Ni2P–MoS2 can be ascribed to the presence of abundant HER active sites in Ni2P nanoparticles and 1T/2H MoS2 nanosheets as well as the effective transfer and separation of charge carriers. Moreover, the coupling sequence of cocatalysts in Cd1-xZnxS–Ni2P–MoS2 is found to be critical in the regulation of charge transfer pathways and thus the resultant photocatalytic efficiency. The results displayed here could facilitate the engineering of high-performance photocatalysts employing multi-component cocatalysts for sustainable solar-to-fuel conversion.
Photocatalytic hydrogen generation from water-splitting holds huge promise for resolving the current energy shortage and environmental issues. Nevertheless, it is still challenging so far to develop non-noble-metal photocatalysts which are efficient toward solar-powered hydrogen evolution reaction (HER). In this work, through an ultrasonic water-bath strategy combined with solvothermal and electrostatic assembly processes, we obtain homogeneous Cd1-xZnxS–Ni2P–MoS2 hybrid nano-spheres consisting of Cd1-xZnxS solid solutions decorated by Ni2P and 1T/2H MoS2 cocatalysts, which demonstrate excellent activity and stability for visible-light-responsive (λ > 420 nm) H2 production. Specifically, the Cd1-xZnxS–Ni2P–MoS2 nano-spheres with 2 wt% Ni2P and 0.2 wt% MoS2 (CZ0.7S–2N–0.2M) exhibit the optimal HER activity of 55.77 mmol∙g-1∙h-1, about 47 and 32 times more than that of CZ0.7S and Pt–CZ0.7S, respectively. The outstanding HER performance of Cd1-xZnxS–Ni2P–MoS2 can be ascribed to the presence of abundant HER active sites in Ni2P nanoparticles and 1T/2H MoS2 nanosheets as well as the effective transfer and separation of charge carriers. Moreover, the coupling sequence of cocatalysts in Cd1-xZnxS–Ni2P–MoS2 is found to be critical in the regulation of charge transfer pathways and thus the resultant photocatalytic efficiency. The results displayed here could facilitate the engineering of high-performance photocatalysts employing multi-component cocatalysts for sustainable solar-to-fuel conversion.
2021, 40(1): 23-30
doi: 10.14102/j.cnki.0254–5861.2011–2774
Abstract:
It is emergent to develop a green waste water adsorbent with high efficiency. Therefore, a type of low-cost, green and environmentally friendly konjac glucomannan (KGM) -silk fibroin (SF) composite aerogels were compounded via simple chemical grafting and vacuum freeze drying, and a study on its adsorption capacity was also conducted. The characterizations of FT-IR, SEM, XRD and DSC indicate that the modified aerogels show a porous network space structure and there is a strong hydrogen bond effect between the KGM and SF molecules, which improves the density, compressive strength and thermal stability of aerogel materials. The adsorption experiments show that KGM-SF aerogels can effectively adsorb the water pollutants Cr(Ⅲ) with a maximal adsorption capacity of 82 mg·g-1. In addition, the adsorption isotherm and dynamic model analysis are used to elaborate the adsorption mechanism of KGM-SF aerogels and explain that the composite aerogels can be single molecule chemisorption. KGM-SF aerogels have potential adsorption capacity.
It is emergent to develop a green waste water adsorbent with high efficiency. Therefore, a type of low-cost, green and environmentally friendly konjac glucomannan (KGM) -silk fibroin (SF) composite aerogels were compounded via simple chemical grafting and vacuum freeze drying, and a study on its adsorption capacity was also conducted. The characterizations of FT-IR, SEM, XRD and DSC indicate that the modified aerogels show a porous network space structure and there is a strong hydrogen bond effect between the KGM and SF molecules, which improves the density, compressive strength and thermal stability of aerogel materials. The adsorption experiments show that KGM-SF aerogels can effectively adsorb the water pollutants Cr(Ⅲ) with a maximal adsorption capacity of 82 mg·g-1. In addition, the adsorption isotherm and dynamic model analysis are used to elaborate the adsorption mechanism of KGM-SF aerogels and explain that the composite aerogels can be single molecule chemisorption. KGM-SF aerogels have potential adsorption capacity.
2021, 40(1): 31-41
doi: 10.14102/j.cnki.0254–5861.2011–2744
Abstract:
The ever-decreasing fossil fuels and the increasing greenhouse effect have caused substantial concern. Solid oxide electrolyser cell (SOEC) with La0.75Sr0.25Cr0.5Mn0.5O3-δ (LSCM) as a cathode was used for CO2 electrolysis to CO. In this work, the metal-oxide interface was constructed on the LSCM framework by in-situ exsolution and impregnation, and the uniform distribution of metal nanoparticles on the LSCM framework was confirmed by spectroscopy techniques and electron microscopy techniques. The existence of three-phase boundary promoted the absorption and electrolysis of CO2. (La0.75Sr0.25)0.9(Cr0.5Mn0.5)0.9(Ni0.5Cu0.5)0.1O3-δ (LSCMNC) showed the best electrolytic CO2 performance at 850 ℃ and exhibited excellent electrocatalytic activity after 100 hours of long-term testing and 8 redox cycles.
The ever-decreasing fossil fuels and the increasing greenhouse effect have caused substantial concern. Solid oxide electrolyser cell (SOEC) with La0.75Sr0.25Cr0.5Mn0.5O3-δ (LSCM) as a cathode was used for CO2 electrolysis to CO. In this work, the metal-oxide interface was constructed on the LSCM framework by in-situ exsolution and impregnation, and the uniform distribution of metal nanoparticles on the LSCM framework was confirmed by spectroscopy techniques and electron microscopy techniques. The existence of three-phase boundary promoted the absorption and electrolysis of CO2. (La0.75Sr0.25)0.9(Cr0.5Mn0.5)0.9(Ni0.5Cu0.5)0.1O3-δ (LSCMNC) showed the best electrolytic CO2 performance at 850 ℃ and exhibited excellent electrocatalytic activity after 100 hours of long-term testing and 8 redox cycles.
2021, 40(1): 42-46
doi: 10.14102/j.cnki.0254–5861.2011–2763
Abstract:
Nanometer blocks of amide-functionalized Fe(Ⅲ)-based metal-organic frameworks, NH2-MIL-53(Fe), were prepared via ultrasonic method without any surfactants at room temperature and atmospheric pressure. The characterization for the as-prepared nano-structured MOFs was established by XRD, SEM, TEM, XPS and N2 adsorption-desorption. The as-prepared sample with high specific surface area (179.9 m2·g-1) showed excellent adsorption for methylene blue in the liquid phase. The as-prepared NH2-MIL-53(Fe) adsorbent seems to be a promising material in practice for organic dye removal from aqueous solution.
Nanometer blocks of amide-functionalized Fe(Ⅲ)-based metal-organic frameworks, NH2-MIL-53(Fe), were prepared via ultrasonic method without any surfactants at room temperature and atmospheric pressure. The characterization for the as-prepared nano-structured MOFs was established by XRD, SEM, TEM, XPS and N2 adsorption-desorption. The as-prepared sample with high specific surface area (179.9 m2·g-1) showed excellent adsorption for methylene blue in the liquid phase. The as-prepared NH2-MIL-53(Fe) adsorbent seems to be a promising material in practice for organic dye removal from aqueous solution.
2021, 40(1): 47-54
doi: 10.14102/j.cnki.0254–5861.2011–2760
Abstract:
Three isostructural lanthanide complexes, namely [Ln(L)3·CH3OH] (Ln = Tb(1), Dy(2), Ho(3), HL = N-(pyridin-2-ylcarbamothioyl)benzamide), were successfully synthesized and characterized by IR, UV, elemental analysis, single-crystal X-ray diffraction and DNA-biding analysis. X-ray single-crystal diffractions show that the family of lanthanide complexes crystallizes in monoclinic C2/c space group. Each lanthanide atom is coordinated with three carbonyl-O atoms, three pyridyl-N atoms and three imine-N atoms from three distinct L–1 ligands, forming a distorted tricapped trigonal prism. The binding properties of complexes with ct-DNA were studied by simulating the physiological environment of human body. The results suggest that compounds could bind with ct-DNA through interaction under a spontaneous process.
Three isostructural lanthanide complexes, namely [Ln(L)3·CH3OH] (Ln = Tb(1), Dy(2), Ho(3), HL = N-(pyridin-2-ylcarbamothioyl)benzamide), were successfully synthesized and characterized by IR, UV, elemental analysis, single-crystal X-ray diffraction and DNA-biding analysis. X-ray single-crystal diffractions show that the family of lanthanide complexes crystallizes in monoclinic C2/c space group. Each lanthanide atom is coordinated with three carbonyl-O atoms, three pyridyl-N atoms and three imine-N atoms from three distinct L–1 ligands, forming a distorted tricapped trigonal prism. The binding properties of complexes with ct-DNA were studied by simulating the physiological environment of human body. The results suggest that compounds could bind with ct-DNA through interaction under a spontaneous process.
2021, 40(1): 55-60
doi: 10.14102/j.cnki.0254–5861.2011–2761
Abstract:
A non-interpenetrated anionic In-MOF (FJU-302) based on a linear H2bpdc and an angled H2cdc as dual-ligands was characterized by FT-IR, TGA and X-ray single-crystal/powder diffraction. FJU-302 crystallizes in the monoclinic system and I41/amd space group with a = 27.1274(8), b = 27.1274(8), c = 29.788(3) Å, V = 21921(2) Å3, Z = 16, Mr = 608.32, Dc = 0.737 g/cm3, F(000) = 4848, μ(CuKα) = 3.659 mm–1, R = 0.0800 and wR = 0.1911 for 5703 observed reflections (I > 2σ(I)), and R = 0.1470 and wR = 0.2342 for all data. In this work, a carbazole based anionic In-MOF (FJU-302) was designed and synthesized, and the proton conductivity from subzero temperature (–30 ℃) to 70 ℃ was measured without additional humidity. FJU-302 presents a max proton conductivity of 6.47 × 10–4 S·cm–1 at 70 ℃, and it can maintain 5.88 × 10–7 S·cm–1 at –30 ℃. This work reports a first carbazole based MOF for proton conductivity at subzero temperature conditions.
A non-interpenetrated anionic In-MOF (FJU-302) based on a linear H2bpdc and an angled H2cdc as dual-ligands was characterized by FT-IR, TGA and X-ray single-crystal/powder diffraction. FJU-302 crystallizes in the monoclinic system and I41/amd space group with a = 27.1274(8), b = 27.1274(8), c = 29.788(3) Å, V = 21921(2) Å3, Z = 16, Mr = 608.32, Dc = 0.737 g/cm3, F(000) = 4848, μ(CuKα) = 3.659 mm–1, R = 0.0800 and wR = 0.1911 for 5703 observed reflections (I > 2σ(I)), and R = 0.1470 and wR = 0.2342 for all data. In this work, a carbazole based anionic In-MOF (FJU-302) was designed and synthesized, and the proton conductivity from subzero temperature (–30 ℃) to 70 ℃ was measured without additional humidity. FJU-302 presents a max proton conductivity of 6.47 × 10–4 S·cm–1 at 70 ℃, and it can maintain 5.88 × 10–7 S·cm–1 at –30 ℃. This work reports a first carbazole based MOF for proton conductivity at subzero temperature conditions.
2021, 40(1): 61-69
doi: 10.14102/j.cnki.0254–5861.2011–2745
Abstract:
Porous single crystals have the characteristics of long-range ordering structure and large specific surface area, which will significantly enhance their electrochemical performance. Here, we report a method different from the conventional porous single crystal growth method. This method is to directly convert single crystal precursors Co3O4 and Fe3O4 into Co2N and Fe2N, and then further reduces them to porous single crystals Co and Fe particles under H2/Ar atmosphere. The removal of O2– in the lattice channel at the pressure of 25~300 torr and the temperature of 300~600 ℃ will promote nitridation of the single-crystalline Co–O and Fe–O frames, and further remove N3– in H2/Ar atmosphere and recrystallize as Co and Fe. These porous single crystals exhibit enhanced electrochemical properties due to their structural coherence and highly active surface. We demonstrated that the aminobenzene yield was up to 91% and the selectivity reached 92% in the electrochemical reduction of nitrobenzene.
Porous single crystals have the characteristics of long-range ordering structure and large specific surface area, which will significantly enhance their electrochemical performance. Here, we report a method different from the conventional porous single crystal growth method. This method is to directly convert single crystal precursors Co3O4 and Fe3O4 into Co2N and Fe2N, and then further reduces them to porous single crystals Co and Fe particles under H2/Ar atmosphere. The removal of O2– in the lattice channel at the pressure of 25~300 torr and the temperature of 300~600 ℃ will promote nitridation of the single-crystalline Co–O and Fe–O frames, and further remove N3– in H2/Ar atmosphere and recrystallize as Co and Fe. These porous single crystals exhibit enhanced electrochemical properties due to their structural coherence and highly active surface. We demonstrated that the aminobenzene yield was up to 91% and the selectivity reached 92% in the electrochemical reduction of nitrobenzene.
2021, 40(1): 70-78
doi: 10.14102/j.cnki.0254–5861.2011–2762
Abstract:
Using a hydrothermal reaction, a novel holmium-mercury compound {[Ho(IA)(HIA)2(H2O)2]2-(Hg3Br8)}n(nHgBr2)·2nNO3 (1, HIA is isonicotinc acid) was synthesized and its crystal structure was characterized by single-crystal X-ray diffraction. Compound 1 crystallizes in monoclinic system, space group P2/c with a = 13.0647(6), b = 9.4659(3), c = 26.0832(14) Å, β = 97.522(4)°, V = 3197.9(2) Å3, C36H36Br10Hg4Ho2N8O22, Mr = 2863.95, Z = 2, Dc = 2.974 g/cm3, μ(MoKα) = 18.331 mm–1 and F(000) = 2575. It displays a two-dimensional (2D) layer-like structure. A solid-state photoluminescence experiment revealed that it shows upconversion green emission. The emission peaks should come from the 5I8 → 5G6 and 5S2 → 5I8 characteristic emission of the 4f electrons of the Ho3+ ion. Compound 1 has a CIE chromaticity coordinate (0.1774, 0.526). A solid-state UV-visible diffuse reflectance spectrum unveiled that this compound has a wide optical band gap of 3.26 eV.
Using a hydrothermal reaction, a novel holmium-mercury compound {[Ho(IA)(HIA)2(H2O)2]2-(Hg3Br8)}n(nHgBr2)·2nNO3 (1, HIA is isonicotinc acid) was synthesized and its crystal structure was characterized by single-crystal X-ray diffraction. Compound 1 crystallizes in monoclinic system, space group P2/c with a = 13.0647(6), b = 9.4659(3), c = 26.0832(14) Å, β = 97.522(4)°, V = 3197.9(2) Å3, C36H36Br10Hg4Ho2N8O22, Mr = 2863.95, Z = 2, Dc = 2.974 g/cm3, μ(MoKα) = 18.331 mm–1 and F(000) = 2575. It displays a two-dimensional (2D) layer-like structure. A solid-state photoluminescence experiment revealed that it shows upconversion green emission. The emission peaks should come from the 5I8 → 5G6 and 5S2 → 5I8 characteristic emission of the 4f electrons of the Ho3+ ion. Compound 1 has a CIE chromaticity coordinate (0.1774, 0.526). A solid-state UV-visible diffuse reflectance spectrum unveiled that this compound has a wide optical band gap of 3.26 eV.
2021, 40(1): 79-84
doi: 10.14102/j.cnki.0254–5861.2011–2769
Abstract:
We have designed and synthesized a new luminescent coordination polymer [Zn2(NO3)(NCP)3(H2O)3]n·2nH2O (1, HNCP = 2-(2-carboxyphenyl) imidazo-[4, 5-f]-1, 10-phenanthroline) under hydrothermal conditions, which has been structurally characterized by single-crystal X-ray diffraction analyses. 1 crystallizes in monoclinic, space group P21/n, with a = 13.7748(3), b = 19.2651(4), c = 19.9543(4) Å, β = 95.339(2)º, V = 5272.35(19) Å3, C60H39.73N13O13.33Zn2, Mr = 1286.80, Dc = 1.621 g/cm3, Z = 4, μ(MoKa) = 2.118, F(000) = 2629, the final R = 0.0598 and wR = 0.1483. In 1, the organic ligand NCP– displays two different bridging modes to connect adjacent Zn(II) ions into a 1D chain along the c-direction. Photoluminescent analyses reveal that 1 exhibits a strong green emission with a fluorescent lifetime of 5.57 ns. The first-principle calculation results show that the luminescence mainly originates from ligand-centered charge transition.
We have designed and synthesized a new luminescent coordination polymer [Zn2(NO3)(NCP)3(H2O)3]n·2nH2O (1, HNCP = 2-(2-carboxyphenyl) imidazo-[4, 5-f]-1, 10-phenanthroline) under hydrothermal conditions, which has been structurally characterized by single-crystal X-ray diffraction analyses. 1 crystallizes in monoclinic, space group P21/n, with a = 13.7748(3), b = 19.2651(4), c = 19.9543(4) Å, β = 95.339(2)º, V = 5272.35(19) Å3, C60H39.73N13O13.33Zn2, Mr = 1286.80, Dc = 1.621 g/cm3, Z = 4, μ(MoKa) = 2.118, F(000) = 2629, the final R = 0.0598 and wR = 0.1483. In 1, the organic ligand NCP– displays two different bridging modes to connect adjacent Zn(II) ions into a 1D chain along the c-direction. Photoluminescent analyses reveal that 1 exhibits a strong green emission with a fluorescent lifetime of 5.57 ns. The first-principle calculation results show that the luminescence mainly originates from ligand-centered charge transition.
2021, 40(1): 85-90
doi: 10.14102/j.cnki.0254–5861.2011–2776
Abstract:
A porous metal-organic framework [C21H20CoF6O7] was synthesized with Co(CH3COO)2·4H2O and CPHFP (2, 2'-bis(4-carboxyphenyl)hexafluoro-propane) under hydrothermal conditions. This FMOF-Co has been characterized by elemental analysis, infrared spectroscopy, thermogravimetric analysis, single-crystal and powder X-ray diffraction. The crystal is of monoclinic space group P21/n with a = 7.8911(2), b = 29.9053(8), c = 10.5811(3) Å, β = 90.193(10)°, V = 2499.70(12) Å3, Z = 4, Mr= 557.3, Dc= 1.481 g·cm–3, F(000)= 1132, μ = 0.768 mm–1, GOOF = 1.035, the final R = 0.0722 and wR = 0.2326 for 6347 observed reflections with I > 2σ(I). The structure of FMOF-Co is constructed form the linkage of Co(II) through CPHFP, forming a 3D net framework. The Kr and Xe uptake values are 0.225 and 0.484 mmol·g–1 at 303 K (100 KPa) with their mol selectivity to be 0.46; while the Kr and Xe uptake values are 0.486 and 0.077 mmol·g–1 at 233 K (100 KPa), with their mol separation being 6.29 at this condition.
A porous metal-organic framework [C21H20CoF6O7] was synthesized with Co(CH3COO)2·4H2O and CPHFP (2, 2'-bis(4-carboxyphenyl)hexafluoro-propane) under hydrothermal conditions. This FMOF-Co has been characterized by elemental analysis, infrared spectroscopy, thermogravimetric analysis, single-crystal and powder X-ray diffraction. The crystal is of monoclinic space group P21/n with a = 7.8911(2), b = 29.9053(8), c = 10.5811(3) Å, β = 90.193(10)°, V = 2499.70(12) Å3, Z = 4, Mr= 557.3, Dc= 1.481 g·cm–3, F(000)= 1132, μ = 0.768 mm–1, GOOF = 1.035, the final R = 0.0722 and wR = 0.2326 for 6347 observed reflections with I > 2σ(I). The structure of FMOF-Co is constructed form the linkage of Co(II) through CPHFP, forming a 3D net framework. The Kr and Xe uptake values are 0.225 and 0.484 mmol·g–1 at 303 K (100 KPa) with their mol selectivity to be 0.46; while the Kr and Xe uptake values are 0.486 and 0.077 mmol·g–1 at 233 K (100 KPa), with their mol separation being 6.29 at this condition.
2021, 40(1): 91-95
doi: 10.14102/j.cnki.0254–5861.2011–2771
Abstract:
A novel nickel(II) complex [Ni(H2tpda)(NCS)2(CH3OH)] was synthesized by using tripyridyldiamine as ligand and Ni(NCS)2 as starting materials, and characterized by a variety of techniques including single-crystal X-ray diffraction, IR spectroscopy and TG-DSC. The single-crystal structure reveals that the complex exhibits as a neutral molecule and that the central atom Ni(II) is octahedrally coordinated by an H2tpda, two NCS- ions and a ligand molecule CH3OH. The 3D supramolecular network is formed through hydrogen bonds and π-π interactions. The complex can catalyze the addition reaction of carbon dioxide and propylene oxide.
A novel nickel(II) complex [Ni(H2tpda)(NCS)2(CH3OH)] was synthesized by using tripyridyldiamine as ligand and Ni(NCS)2 as starting materials, and characterized by a variety of techniques including single-crystal X-ray diffraction, IR spectroscopy and TG-DSC. The single-crystal structure reveals that the complex exhibits as a neutral molecule and that the central atom Ni(II) is octahedrally coordinated by an H2tpda, two NCS- ions and a ligand molecule CH3OH. The 3D supramolecular network is formed through hydrogen bonds and π-π interactions. The complex can catalyze the addition reaction of carbon dioxide and propylene oxide.
Synthesis, Structure and Properties of a New Molybdate-tellurite Compound with 2D Triangular Lattice
2021, 40(1): 96-102
doi: 10.14102/j.cnki.0254–5861.2011–2778
Abstract:
A new 3d transition-metal molybdate-tellurite (NH4)2Co(TeMo2O9)2 was obtained through a conventional hydrothermal method. This compound was confirmed to crystallize in the monoclinic system of space group P21/c with a = 10.5133(5), b = 10.6456(5), c = 7.6078(5) Å, β = 108.879(6)º, V = 805.66(8) Å3, Z = 2, Mr = 1021.97, Dc = 4.213 g/cm3, μ = 7.685 mm–1, F(000) = 930, the final R = 0.0399 and wR = 0.1025 for 1580 observed reflections with I > 2σ(I), showing a tunnel structure with spin triangle-lattice composed by CoO6 octahedra. Magnetic and heat capacity measurements confirmed a paramagnetic behavior down to 2 K with a negative Weiss temperature of –20 K, suggesting remarkable spin frustration in the system.
A new 3d transition-metal molybdate-tellurite (NH4)2Co(TeMo2O9)2 was obtained through a conventional hydrothermal method. This compound was confirmed to crystallize in the monoclinic system of space group P21/c with a = 10.5133(5), b = 10.6456(5), c = 7.6078(5) Å, β = 108.879(6)º, V = 805.66(8) Å3, Z = 2, Mr = 1021.97, Dc = 4.213 g/cm3, μ = 7.685 mm–1, F(000) = 930, the final R = 0.0399 and wR = 0.1025 for 1580 observed reflections with I > 2σ(I), showing a tunnel structure with spin triangle-lattice composed by CoO6 octahedra. Magnetic and heat capacity measurements confirmed a paramagnetic behavior down to 2 K with a negative Weiss temperature of –20 K, suggesting remarkable spin frustration in the system.
2021, 40(1): 103-108
doi: 10.14102/j.cnki.0254–5861.2011–2735
Abstract:
A new complex [Zn(3,4-APT)2(H2O)4]·8H2O (1, 3,4-HAPT = 4-(5-(pyridin-3-yl)-4H-1,2,4-triazol-3-yl) benzoic acid) has been prepared and characterized by elemental analysis, X-ray single-crystal diffraction analysis, thermogravimetric analysis and infrared spectrum analysis. Theoretical calculation based on density functional theory (DFT) is also employed to explicate frontier orbitals of 3,4-HAPT. X-ray single-crystal diffraction analysis reveals that 1 belongs to the triclinic system, space group P\begin{document}$ \overline 1 $\end{document}
A new complex [Zn(3,4-APT)2(H2O)4]·8H2O (1, 3,4-HAPT = 4-(5-(pyridin-3-yl)-4H-1,2,4-triazol-3-yl) benzoic acid) has been prepared and characterized by elemental analysis, X-ray single-crystal diffraction analysis, thermogravimetric analysis and infrared spectrum analysis. Theoretical calculation based on density functional theory (DFT) is also employed to explicate frontier orbitals of 3,4-HAPT. X-ray single-crystal diffraction analysis reveals that 1 belongs to the triclinic system, space group P
2021, 40(1): 109-113
doi: 10.14102/j.cnki.0254–5861.2011–2753
Abstract:
The target compound (Z)-4-[3-(4-methyl-1,2,3-thiadiazol-5-yl)-3-(4-trifluoromethylphenyl)acryloyl]morpholine was synthesized by the nucleophilic substitution, Horner-Emmons reaction, ester hydrolysis, and condensation. Its structure was characterized by NMR, H RMS and single-crystal X-ray diffraction. The crystal of the target compound belongs to monoclinic system, space group P21 with a = 11.5058(15), b = 6.6626(10), c = 23.184(3) Å, V = 1777.3(4) Å3, Z = 8, Dc = 1.496 Mg/m3, F(000) = 792 and μ = 0.229 mm–1. X-ray analysis indicated C–H⋯O intermolecular H-bonds in this crystal structure. The target compound exhibited 53% curative activity against TMV.
The target compound (Z)-4-[3-(4-methyl-1,2,3-thiadiazol-5-yl)-3-(4-trifluoromethylphenyl)acryloyl]morpholine was synthesized by the nucleophilic substitution, Horner-Emmons reaction, ester hydrolysis, and condensation. Its structure was characterized by NMR, H RMS and single-crystal X-ray diffraction. The crystal of the target compound belongs to monoclinic system, space group P21 with a = 11.5058(15), b = 6.6626(10), c = 23.184(3) Å, V = 1777.3(4) Å3, Z = 8, Dc = 1.496 Mg/m3, F(000) = 792 and μ = 0.229 mm–1. X-ray analysis indicated C–H⋯O intermolecular H-bonds in this crystal structure. The target compound exhibited 53% curative activity against TMV.
2021, 40(1): 114-124
doi: 10.14102/j.cnki.0254–5861.2011–2773
Abstract:
Two new alkali metal germanophosphates, namely, Na3[Ge(OH)(PO4)2]·2H2O and Li2Na[GeO(HPO4)(PO4)], have been prepared by solvothermal method, and their crystal structures were determined by single-crystal X-ray diffraction. The title two compounds crystalize in the same orthorhombic space group Pbcm (No. 57) and feature similar chain-like structure which is built from zig-zag GeO6 octahedral thread loop branched by PO4 tetrahedra. For Na3[Ge(OH)(PO4)2]·2H2O, a = 10.1650(9), b = 13.1975(12), c = 6.9751(7) Å, V = 935.73(15) Å3, Z = 4, R = 0.0356 and wR = 0.1109; and for Li2Na[GeO(HPO4)(PO4)], a = 6.9855(5), b = 14.5809(18), c = 6.6620(5) Å, V = 678.56(11) Å3, Z = 4, R = 0.0286, and wR = 0.0762. The partial substitution of Na ions by Li ions not only significantly influences the total structural features and the water molecule contents, but also impacts on their thermal stabilities. Li2Na[GeO(HPO4)(PO4)] is thermally stable up to 400 ℃, whereas only 150 ℃ for Na3[Ge(OH)(PO4)2]·2H2O.
Two new alkali metal germanophosphates, namely, Na3[Ge(OH)(PO4)2]·2H2O and Li2Na[GeO(HPO4)(PO4)], have been prepared by solvothermal method, and their crystal structures were determined by single-crystal X-ray diffraction. The title two compounds crystalize in the same orthorhombic space group Pbcm (No. 57) and feature similar chain-like structure which is built from zig-zag GeO6 octahedral thread loop branched by PO4 tetrahedra. For Na3[Ge(OH)(PO4)2]·2H2O, a = 10.1650(9), b = 13.1975(12), c = 6.9751(7) Å, V = 935.73(15) Å3, Z = 4, R = 0.0356 and wR = 0.1109; and for Li2Na[GeO(HPO4)(PO4)], a = 6.9855(5), b = 14.5809(18), c = 6.6620(5) Å, V = 678.56(11) Å3, Z = 4, R = 0.0286, and wR = 0.0762. The partial substitution of Na ions by Li ions not only significantly influences the total structural features and the water molecule contents, but also impacts on their thermal stabilities. Li2Na[GeO(HPO4)(PO4)] is thermally stable up to 400 ℃, whereas only 150 ℃ for Na3[Ge(OH)(PO4)2]·2H2O.
2021, 40(1): 125-135
doi: 10.14102/j.cnki.0254–5861.2011–2781
Abstract:
A high capacitance RuO2-ZrO2 coating was prepared by thermal decomposition method. Extended X-ray absorption fine structure (EXAFS), X-ray diffraction (XRD), high-resolution transmission electron microscope (HRTEM) and ab initio calculations were applied to understand the role of the microstructure in the acquisition of high specific capacitance of RuO2-based oxides. The results show that the RuO2-ZrO2 oxide prepared at critical crystallization temperature can be considered to be quasi-amorphous or microcrystalline (A short-range ordered crystal structure can be seen from the TEM image, but no diffraction peaks can be seen from the XRD diffraction patterns). And this RuO2-ZrO2 was identified as a solid solution with high solid solubility. It referred to herein as a quasi-amorphous solid solution. Such a special microstructure was conducive for "synergistic catalysis" owing to the cationic interaction and thus could gain high "active site density" and high "active surface", thus developing high specific capacitance.
A high capacitance RuO2-ZrO2 coating was prepared by thermal decomposition method. Extended X-ray absorption fine structure (EXAFS), X-ray diffraction (XRD), high-resolution transmission electron microscope (HRTEM) and ab initio calculations were applied to understand the role of the microstructure in the acquisition of high specific capacitance of RuO2-based oxides. The results show that the RuO2-ZrO2 oxide prepared at critical crystallization temperature can be considered to be quasi-amorphous or microcrystalline (A short-range ordered crystal structure can be seen from the TEM image, but no diffraction peaks can be seen from the XRD diffraction patterns). And this RuO2-ZrO2 was identified as a solid solution with high solid solubility. It referred to herein as a quasi-amorphous solid solution. Such a special microstructure was conducive for "synergistic catalysis" owing to the cationic interaction and thus could gain high "active site density" and high "active surface", thus developing high specific capacitance.
2021, 40(1): 136-144
doi: 10.14102/j.cnki.0254–5861.2011–2790
Abstract:
To search for proper alternatives to improve the magnetic properties of Nd2Fe14B, using first-principles density functional theory calculations we have systematically studied the R2M14B (R = lanthanides from La to Lu; M = Mn, Fe, Co, and Ni) compounds with the isomorphic structure of Nd2Fe14B. The results show that for rare-earth elements, Pr is the most suitable choice for considering as an alternative of Nd. As for the substitution of Fe in Nd2Fe14B by other transition-metal elements, Co is much more suitable than Mn and Ni because the latter two result in too significant reduction of the magnetic moment.
To search for proper alternatives to improve the magnetic properties of Nd2Fe14B, using first-principles density functional theory calculations we have systematically studied the R2M14B (R = lanthanides from La to Lu; M = Mn, Fe, Co, and Ni) compounds with the isomorphic structure of Nd2Fe14B. The results show that for rare-earth elements, Pr is the most suitable choice for considering as an alternative of Nd. As for the substitution of Fe in Nd2Fe14B by other transition-metal elements, Co is much more suitable than Mn and Ni because the latter two result in too significant reduction of the magnetic moment.
