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2021 Volume 40 Issue 9
2021, 40(9): 1113-1121
doi: 10.14102/j.cnki.0254–5861.2011–3143
Abstract:
The geometric and electronic structures of the derivatives of 4-nitro-5-(5-nitroimino-1, 2, 4-triazol-3-yl)-2H-1, 2, 3-triazolate (named A~J) are explored employing density functional theory (DFT) calculations at the B3LYP/6-311G** level of theory. Based on the optimized molecular structures, the heats of formation (HOF) are obtained, and the electronic properties, density and molecular sensitivity by characteristic heights (H50) are discussed. Besides, the detonation performances (detonation velocity, detonation pressure) are estimated via Kamlet-Jacobs (K-J) formula. Compounds B (H50 = 29.4 cm, ρ = 1.91 g/cm3, Q = 1563.04 cal/g, P = 36.05 GPa, D = 8.95 km/s) and H (H50 = 31.9 cm, ρ = 1.80 g/cm3, Q = 1610.09 cal/g, P = 37.31 GPa, D = 9.12 km/s) have positive HOFs and remarkable insensitivity and good detonation performance, strongly suggesting them as the acceptable new-type explosive. The initiating power surpasses conventional primary explosives, such as HMX. The outstanding detonation power of compounds B and H contributes to its future prospects as a promising green primary explosive.
The geometric and electronic structures of the derivatives of 4-nitro-5-(5-nitroimino-1, 2, 4-triazol-3-yl)-2H-1, 2, 3-triazolate (named A~J) are explored employing density functional theory (DFT) calculations at the B3LYP/6-311G** level of theory. Based on the optimized molecular structures, the heats of formation (HOF) are obtained, and the electronic properties, density and molecular sensitivity by characteristic heights (H50) are discussed. Besides, the detonation performances (detonation velocity, detonation pressure) are estimated via Kamlet-Jacobs (K-J) formula. Compounds B (H50 = 29.4 cm, ρ = 1.91 g/cm3, Q = 1563.04 cal/g, P = 36.05 GPa, D = 8.95 km/s) and H (H50 = 31.9 cm, ρ = 1.80 g/cm3, Q = 1610.09 cal/g, P = 37.31 GPa, D = 9.12 km/s) have positive HOFs and remarkable insensitivity and good detonation performance, strongly suggesting them as the acceptable new-type explosive. The initiating power surpasses conventional primary explosives, such as HMX. The outstanding detonation power of compounds B and H contributes to its future prospects as a promising green primary explosive.
2021, 40(9): 1122-1130
doi: 10.14102/j.cnki.0254–5861.2011–3206
Abstract:
Two new complexes, namely [Cd2(L)(pycy)(Cl)]·2H2O (1) and [Cu(HL)(H2btac)]·2H2O, have been synthesized by the reaction of the corresponding metal salts with mixed ligands including 1-(1H-imidazol-4-yl)-4-(4H-tetrazol-5-yl)benzene (HL), 2, 6-pyridinedicarboxylic acid (H2pycy) and 1, 2, 4, 5-benzenetetracarboxylic acid (H4btac), and characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis and powder X-ray diffraction (PXRD). Complex 1 crystallizes in triclinic, space group P\begin{document}$ \overline 1 $\end{document} \begin{document}$ \overline 1 $\end{document}
Two new complexes, namely [Cd2(L)(pycy)(Cl)]·2H2O (1) and [Cu(HL)(H2btac)]·2H2O, have been synthesized by the reaction of the corresponding metal salts with mixed ligands including 1-(1H-imidazol-4-yl)-4-(4H-tetrazol-5-yl)benzene (HL), 2, 6-pyridinedicarboxylic acid (H2pycy) and 1, 2, 4, 5-benzenetetracarboxylic acid (H4btac), and characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis and powder X-ray diffraction (PXRD). Complex 1 crystallizes in triclinic, space group P
2021, 40(9): 1131-1137
doi: 10.14102/j.cnki.0254–5861.2011–3139
Abstract:
Helix as essential molecular chiral phenomenon at supramolecular level offers an affective method to study chiral characteristic of homochiral coordination polymers (CPs). Herein, two homochiral CPs [Cd((R)-CBA)2(3, 5-DIT)]n ((R)-H2CBA = (R)-4-(1-carboxyethoxy) benzoic acid, 3, 5-DIT = 3, 5-di(1H-imidazol-1-yl)toluene, 1-R) and [Zn((R)-CBA)(3, 5-DIT)]n (2-R) were synthesized under hydrothermal conditions. In complex 1-R, only a helical chain was built by chiral ligands (R)-CBA2-, ancillary ligands 3, 5-DIT and Cd(Ⅱ) ions. After Cd(Ⅱ) ions were replaced by Zn(Ⅱ) ions under similar reaction system, Zn(Ⅱ), (R)-CBA2- and/or 3, 5-DIT formed six types of helices, resulting in complex 2-R. So, the metal ions played a key role in the construction of helical structures. Complexes 1-R and 2-R were also characterized by elemental analysis, PXRD, TGA, CD and UV-visible absorptions. In addition, complexes 1-R and 2-R exhibited different photoluminescence behaviors in solid sate compared to free ligand (R)-H2CBA.
Helix as essential molecular chiral phenomenon at supramolecular level offers an affective method to study chiral characteristic of homochiral coordination polymers (CPs). Herein, two homochiral CPs [Cd((R)-CBA)2(3, 5-DIT)]n ((R)-H2CBA = (R)-4-(1-carboxyethoxy) benzoic acid, 3, 5-DIT = 3, 5-di(1H-imidazol-1-yl)toluene, 1-R) and [Zn((R)-CBA)(3, 5-DIT)]n (2-R) were synthesized under hydrothermal conditions. In complex 1-R, only a helical chain was built by chiral ligands (R)-CBA2-, ancillary ligands 3, 5-DIT and Cd(Ⅱ) ions. After Cd(Ⅱ) ions were replaced by Zn(Ⅱ) ions under similar reaction system, Zn(Ⅱ), (R)-CBA2- and/or 3, 5-DIT formed six types of helices, resulting in complex 2-R. So, the metal ions played a key role in the construction of helical structures. Complexes 1-R and 2-R were also characterized by elemental analysis, PXRD, TGA, CD and UV-visible absorptions. In addition, complexes 1-R and 2-R exhibited different photoluminescence behaviors in solid sate compared to free ligand (R)-H2CBA.
2021, 40(9): 1138-1144
doi: 10.14102/j.cnki.0254–5861.2011–3133
Abstract:
Coordination polymers with structurally designable and energy, fluorescence, electrical etc. properties, are expected to become the next generation of multifunctional materials. A new compound, Zn(OAc)SPhNH (HSPhNH2 = 4-aminophenol), was hydrothermally synthesized using 4-aminophenol as template and balance anion. The single-crystal X-ray diffraction showed a two-dimensional (2D) structure constructed of Zn(OAc)+ and SPhNH-. This compound exhibited typical semiconductive behavior, whose conductivity increased with the raise of temperature. Moreover, the conductivity was positively correlated with humidity. The compound also showed blue light emission property, which indicates great potential applications in light-emitting diodes.
Coordination polymers with structurally designable and energy, fluorescence, electrical etc. properties, are expected to become the next generation of multifunctional materials. A new compound, Zn(OAc)SPhNH (HSPhNH2 = 4-aminophenol), was hydrothermally synthesized using 4-aminophenol as template and balance anion. The single-crystal X-ray diffraction showed a two-dimensional (2D) structure constructed of Zn(OAc)+ and SPhNH-. This compound exhibited typical semiconductive behavior, whose conductivity increased with the raise of temperature. Moreover, the conductivity was positively correlated with humidity. The compound also showed blue light emission property, which indicates great potential applications in light-emitting diodes.
2021, 40(9): 1145-1151
doi: 10.14102/j.cnki.0254–5861.2011–3130
Abstract:
A binuclear Cu(I) complex [Cu(PCNP)(mepypz)]2(BF4)2 (1, PCNP = 2, 6-bis(diphenylphosphine)-benzonitrile, mepypz = 2-(1H-pyrazol-3-yl)pyridine) was synthesized from the reaction of Cu(CH3CN)4BF4, PCNP and mepypz in CH2Cl2 at room temperature. The compound was characterized by NMR, UV-vis and X-ray single-crystal structure analysis. It crystallizes in monoclinic space group P21/c with a = 14.0139(5), b = 11.8149(3), c = 27.1248(10) Å, β = 96.686(4)°, V = 4460.6(3) Å3, Z = 2, Mr = 1561.97, Dc = 1.163 g/cm3, F(000) = 1600.0, μ = 1.774 mm–1, GOOF = 1.071, the final R = 0.0523 and wR = 0.1412 for 7919 observed reflections with I > 2σ(I). The Cu atoms in the complex are four-coordinated and adopt a distorted tetrahedral coordination geometry. In the solid state, the complex exhibits yellowish-green emission with a peak wavelength of 546 nm, a lifetime of 390 μs, and a quantum yield of 0.45 at room temperature. The temperature-dependent investigation of luminescent properties suggests that the complex emits thermally activated delayed fluorescence (TADF) at room temperature.
A binuclear Cu(I) complex [Cu(PCNP)(mepypz)]2(BF4)2 (1, PCNP = 2, 6-bis(diphenylphosphine)-benzonitrile, mepypz = 2-(1H-pyrazol-3-yl)pyridine) was synthesized from the reaction of Cu(CH3CN)4BF4, PCNP and mepypz in CH2Cl2 at room temperature. The compound was characterized by NMR, UV-vis and X-ray single-crystal structure analysis. It crystallizes in monoclinic space group P21/c with a = 14.0139(5), b = 11.8149(3), c = 27.1248(10) Å, β = 96.686(4)°, V = 4460.6(3) Å3, Z = 2, Mr = 1561.97, Dc = 1.163 g/cm3, F(000) = 1600.0, μ = 1.774 mm–1, GOOF = 1.071, the final R = 0.0523 and wR = 0.1412 for 7919 observed reflections with I > 2σ(I). The Cu atoms in the complex are four-coordinated and adopt a distorted tetrahedral coordination geometry. In the solid state, the complex exhibits yellowish-green emission with a peak wavelength of 546 nm, a lifetime of 390 μs, and a quantum yield of 0.45 at room temperature. The temperature-dependent investigation of luminescent properties suggests that the complex emits thermally activated delayed fluorescence (TADF) at room temperature.
2021, 40(9): 1152-1160
doi: 10.14102/j.cnki.0254–5861.2011–3129
Abstract:
Three novel coordination polymers, [Zn(suc)(o-bix)]n (1), [Zn(suc)(m-bix)·H2O]n (2) and [Zn2(suc)2(p-bix)2·4H2O]n (3) (H2suc = succinic acid, o-bix = 1, 2-bis(imidazol-1-ylmethyl)-benzene, m-bix = 1, 3-bis(imidazol-1-ylmethyl)-benzene, p-bix = 1, 4-bis(imidazol-1-ylmethyl)-benzene), have been synthesized and structurally characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, powder X-ray diffraction, and single-crystal X-ray diffraction. These three coordination polymers present various structures originated from auxiliary N-donor ligands with different configurations. Compound 1 shows a 2D network with 44-sql topology. Compound 2 exhibits an infinite chain, and the adjacent chains are extended into a 2D sheet by π-π stacking interactions. Changing the conformation of the N-donor ligand leads to 3 featuring a 3D framework with a novel 4-connected (65·8) topology. In addition, the solid-state photoluminescent properties of compounds 1~3 are investigated.
Three novel coordination polymers, [Zn(suc)(o-bix)]n (1), [Zn(suc)(m-bix)·H2O]n (2) and [Zn2(suc)2(p-bix)2·4H2O]n (3) (H2suc = succinic acid, o-bix = 1, 2-bis(imidazol-1-ylmethyl)-benzene, m-bix = 1, 3-bis(imidazol-1-ylmethyl)-benzene, p-bix = 1, 4-bis(imidazol-1-ylmethyl)-benzene), have been synthesized and structurally characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, powder X-ray diffraction, and single-crystal X-ray diffraction. These three coordination polymers present various structures originated from auxiliary N-donor ligands with different configurations. Compound 1 shows a 2D network with 44-sql topology. Compound 2 exhibits an infinite chain, and the adjacent chains are extended into a 2D sheet by π-π stacking interactions. Changing the conformation of the N-donor ligand leads to 3 featuring a 3D framework with a novel 4-connected (65·8) topology. In addition, the solid-state photoluminescent properties of compounds 1~3 are investigated.
2021, 40(9): 1161-1168
doi: 10.14102/j.cnki.0254–5861.2011–3123
Abstract:
Three dinuclear cyanide-bridged complexes [FeII(PY5OMe2)CNMII(PY5OMe2)](OTf)3 (M = Fe 1, M = Co 2, M = Mn 3) (PY5OMe2 = 2, 6-bis-((2-pyridyl)methoxymethane)pyridine OTf = CF3SO3-) have been synthesized and characterized. Single-crystal diffraction analyses show these three dinuclear compounds are very similar in structure. The measured ν(CN) results for compounds 1~3 suggest that Mn2+ is electron-poorer than Fe2+ and Co2+. Meanwhile, the temperature dependence of magnetic susceptibilities of complexes 1~3 reveals that in these three complexes, all the cyanide-carbon coordinated Fe(II) is low-spin, and Co(II) for 2 and Mn(II) for 3 are both in a high-spin state through 2~400 K but the cyanide-nitrogen coordinated Fe(II) for complex 1 exhibits spin crossover (SCO) behavior over 300 K and a hysteresis of 36 K in both cooling and heating modes.
Three dinuclear cyanide-bridged complexes [FeII(PY5OMe2)CNMII(PY5OMe2)](OTf)3 (M = Fe 1, M = Co 2, M = Mn 3) (PY5OMe2 = 2, 6-bis-((2-pyridyl)methoxymethane)pyridine OTf = CF3SO3-) have been synthesized and characterized. Single-crystal diffraction analyses show these three dinuclear compounds are very similar in structure. The measured ν(CN) results for compounds 1~3 suggest that Mn2+ is electron-poorer than Fe2+ and Co2+. Meanwhile, the temperature dependence of magnetic susceptibilities of complexes 1~3 reveals that in these three complexes, all the cyanide-carbon coordinated Fe(II) is low-spin, and Co(II) for 2 and Mn(II) for 3 are both in a high-spin state through 2~400 K but the cyanide-nitrogen coordinated Fe(II) for complex 1 exhibits spin crossover (SCO) behavior over 300 K and a hysteresis of 36 K in both cooling and heating modes.
2021, 40(9): 1169-1176
doi: 10.14102/j.cnki.0254–5861.2011–3119
Abstract:
A novel complex, [Mn(C6H12N4)2(H2O)4][Mn(H2O)6][SO4]2·6H2O, was synthesized and hexagonal single crystals with centimeter-scale sizes were obtained by the method of solvent evaporation. It was characterized by elemental analysis, infrared spectrum, thermogravimetric analysis and X-ray single-crystal diffraction. The complex belongs to triclinic crystal system, space group P\begin{document}$ \overline 1 $\end{document}
A novel complex, [Mn(C6H12N4)2(H2O)4][Mn(H2O)6][SO4]2·6H2O, was synthesized and hexagonal single crystals with centimeter-scale sizes were obtained by the method of solvent evaporation. It was characterized by elemental analysis, infrared spectrum, thermogravimetric analysis and X-ray single-crystal diffraction. The complex belongs to triclinic crystal system, space group P
2021, 40(9): 1177-1182
doi: 10.14102/j.cnki.0254–5861.2011–3101
Abstract:
A novel metalloviologen complex {[Cd(PhSQ)(HTBC)(H2O)2]·1.25H2O}n (1) based on N-(4-sulfo-phenyl)-4, 4΄-bipyridinium (PhSQ) and monoprotonated trimesic acid (HTBC) has been prepared and structurally characterized. Complex 1 has been characterized by elemental analysis, IR, thermogravimetric analyses, UV-Vis spectra and X-ray crystallography. The coordination geometry of Cd(II) ion is a pentagonal bipyramid. Complex 1 displays a zigzag chain along the b axis, and such chains are extended into a 2D layer supramolecular network through hydrogen bonding and π…π interactions. Moreover, complex 1 exhibits reversible photochromic and switchable luminescent behaviors via UV light irradiation at room temperature induced by the photogenerated radicals via a photo-induced electron transfer (PET) mechanism.
A novel metalloviologen complex {[Cd(PhSQ)(HTBC)(H2O)2]·1.25H2O}n (1) based on N-(4-sulfo-phenyl)-4, 4΄-bipyridinium (PhSQ) and monoprotonated trimesic acid (HTBC) has been prepared and structurally characterized. Complex 1 has been characterized by elemental analysis, IR, thermogravimetric analyses, UV-Vis spectra and X-ray crystallography. The coordination geometry of Cd(II) ion is a pentagonal bipyramid. Complex 1 displays a zigzag chain along the b axis, and such chains are extended into a 2D layer supramolecular network through hydrogen bonding and π…π interactions. Moreover, complex 1 exhibits reversible photochromic and switchable luminescent behaviors via UV light irradiation at room temperature induced by the photogenerated radicals via a photo-induced electron transfer (PET) mechanism.
2021, 40(9): 1183-1193
doi: 10.14102/j.cnki.0254–5861.2011–3099
Abstract:
Two new hybrid chloroantimonates, namely, [Prmim]3SbCl6 (1, Prmim = 1-propyl-3-methylimi-dazolium) and [Hmim]3SbCl6 (2, Hmim = 1-hexyl-3-methylimidazolium), were synthesized in ionic liquids (ILs) with the yields of 97% and 72%, respectively. Single-crystal X-ray diffraction (SCXRD) study reveals that 1 crystallizes in monoclinic, space group Pn with a = 15.2988(12), b = 13.6388(10), c = 15.6761(13) Å, β = 98.677(7)°, V = 3233.5(4) Å3, Z = 4, Dc = 1.459 g·cm-3, F(000) = 1440, μ = 1.370 mm-1, R = 0.0589 and wR = 0.1366 (I > 2σ(I)); 2 crystallizes in the hexagonal space group of P63 with a = 27.7471(6), b = 27.7471(6), c = 8.9811(2) Å, V = 5988.2(3) Å3, Z = 6, Dc = 1.391 g·cm-3, F(000) = 2592, μ = 1.121 mm-1, R = 0.0420 and wR = 0.0726 (I > 2σ(I)). The photophysical properties of the title compounds were studied by solid-state optical absorption, photoluminescent excitation/emission (PLE/PL), PL decay spectra and photoluminescent quantum yield (PLQY). 1 and 2 exhibit PL peaks at 627 and 607 nm, Stokes shifts of 257 and 242 nm, and PLQY of 32.5% and 49.2%, respectively. The distinct photo physical characteristics of 1 and 2 are highly related to the distortion extent of the [SbCl6]3- unit.
Two new hybrid chloroantimonates, namely, [Prmim]3SbCl6 (1, Prmim = 1-propyl-3-methylimi-dazolium) and [Hmim]3SbCl6 (2, Hmim = 1-hexyl-3-methylimidazolium), were synthesized in ionic liquids (ILs) with the yields of 97% and 72%, respectively. Single-crystal X-ray diffraction (SCXRD) study reveals that 1 crystallizes in monoclinic, space group Pn with a = 15.2988(12), b = 13.6388(10), c = 15.6761(13) Å, β = 98.677(7)°, V = 3233.5(4) Å3, Z = 4, Dc = 1.459 g·cm-3, F(000) = 1440, μ = 1.370 mm-1, R = 0.0589 and wR = 0.1366 (I > 2σ(I)); 2 crystallizes in the hexagonal space group of P63 with a = 27.7471(6), b = 27.7471(6), c = 8.9811(2) Å, V = 5988.2(3) Å3, Z = 6, Dc = 1.391 g·cm-3, F(000) = 2592, μ = 1.121 mm-1, R = 0.0420 and wR = 0.0726 (I > 2σ(I)). The photophysical properties of the title compounds were studied by solid-state optical absorption, photoluminescent excitation/emission (PLE/PL), PL decay spectra and photoluminescent quantum yield (PLQY). 1 and 2 exhibit PL peaks at 627 and 607 nm, Stokes shifts of 257 and 242 nm, and PLQY of 32.5% and 49.2%, respectively. The distinct photo physical characteristics of 1 and 2 are highly related to the distortion extent of the [SbCl6]3- unit.
2021, 40(9): 1194-1204
doi: 10.14102/j.cnki.0254–5861.2011–3111
Abstract:
A series of near-infrared (NIR) down-conversion phosphors of La3Ga5SiO14 (LGS): Ce3+/Yb3+ were synthesized via high-temperature solid-state reaction. Under excitation at 345 nm, the phosphors show strong NIR emission around 978 nm, which matches well with the optimal spectral response of crystalline silicon (c-Si) solar cells. The emission spectra and decay curves were used to demonstrate the energy transfer from Ce3+ to Yb3+. The energy transfer mechanism was discussed in detail, indicating that the energy transfer from Ce3+ to Yb3+ is dominated by a single photon process, and the energy transfer efficiency is up to 51%. In addition, La3Ga5-zAlzSiO14 (z = 0, 1, 2, 3): Ce3+/Yb3+ were also synthesized. The NIR emission intensity of La3Ga2Al3SiO14: 1%Ce3+/5%Yb3+ is 4.6 times that of LGS: 1%Ce3+/5%Yb3+, and the thermal relaxation was used to explain this phenomenon. The results show that La3Ga5-zAlzSiO14 (z = 0, 1, 2, 3): 1%Ce3+/5%Yb3+ phosphors have the potential to increase the conversion efficiency of c-Si solar cells.
A series of near-infrared (NIR) down-conversion phosphors of La3Ga5SiO14 (LGS): Ce3+/Yb3+ were synthesized via high-temperature solid-state reaction. Under excitation at 345 nm, the phosphors show strong NIR emission around 978 nm, which matches well with the optimal spectral response of crystalline silicon (c-Si) solar cells. The emission spectra and decay curves were used to demonstrate the energy transfer from Ce3+ to Yb3+. The energy transfer mechanism was discussed in detail, indicating that the energy transfer from Ce3+ to Yb3+ is dominated by a single photon process, and the energy transfer efficiency is up to 51%. In addition, La3Ga5-zAlzSiO14 (z = 0, 1, 2, 3): Ce3+/Yb3+ were also synthesized. The NIR emission intensity of La3Ga2Al3SiO14: 1%Ce3+/5%Yb3+ is 4.6 times that of LGS: 1%Ce3+/5%Yb3+, and the thermal relaxation was used to explain this phenomenon. The results show that La3Ga5-zAlzSiO14 (z = 0, 1, 2, 3): 1%Ce3+/5%Yb3+ phosphors have the potential to increase the conversion efficiency of c-Si solar cells.
2021, 40(9): 1205-1212
doi: 10.14102/j.cnki.0254–5861.2011–3120
Abstract:
In this paper, a β-C-pyranogalactoside (IX) was synthesized from D-galactose through a nine-step reaction with a total yield of 32% under the palladium catalyst, and its structure was characterized by nuclear magnetic resonance (NMR) and high-resolution electrospray ionization mass spectrometry (HR-ESI-MS). The absolute configuration of this pyranogalactoside was confirmed with a Flack parameter of –0.01(6) by X-ray crystallography using a Cu radiation source. Compound (IX), C12H19NO7, crystal data: monoclinic system, space group P212121, a = 8.53480(10), b = 9.4207(2), c = 18.1308(3) Å, V = 1457.79(4) Å3, Z = 4, F(000) = 616, Dc = 1.318 g/cm3, μ = 0.931 mm−1, R = 0.0294 and wR = 0.0752 for 2875 independent reflections (Rint = 0.0163) and 2857 observed ones (I > 2σ(I)).
In this paper, a β-C-pyranogalactoside (IX) was synthesized from D-galactose through a nine-step reaction with a total yield of 32% under the palladium catalyst, and its structure was characterized by nuclear magnetic resonance (NMR) and high-resolution electrospray ionization mass spectrometry (HR-ESI-MS). The absolute configuration of this pyranogalactoside was confirmed with a Flack parameter of –0.01(6) by X-ray crystallography using a Cu radiation source. Compound (IX), C12H19NO7, crystal data: monoclinic system, space group P212121, a = 8.53480(10), b = 9.4207(2), c = 18.1308(3) Å, V = 1457.79(4) Å3, Z = 4, F(000) = 616, Dc = 1.318 g/cm3, μ = 0.931 mm−1, R = 0.0294 and wR = 0.0752 for 2875 independent reflections (Rint = 0.0163) and 2857 observed ones (I > 2σ(I)).
2021, 40(9): 1213-1222
doi: 10.14102/j.cnki.0254–5861.2011–3118
Abstract:
Electroreduction of CO2 into chemicals is of great importance in the global carbon balance. Although noble-metal based catalysts and single-atom catalysts (SACs) are known to be active for CO2 electroreduction reaction (CO2RR), the high cost of noble-metal and the lack of effective synthesis approaches to prepare SACs have tremendously hindered the application. Non-metal doped carbon materials have attracted great interest because of their reasonable cost, chemical stability and excellent electrical conductivity. Nevertheless, the design and fabrication of highly efficient non-metal doped carbon electrocatalysts for CO2RR to meet industry demands still remains a big challenge. Herein, triphenylphosphine@covalent triazine framework (CTF) composites were employed as precursors to fabricate N, P dual-doped porous carbon catalysts PCTF-X-Y (X represents the carbonization temperature, and Y represents the mass ratio of CTF to triphenylphosphine) for CO2RR. Due to the high specific surface areas and synergistic effect between N and P, the obtained PCTF-1000-5 exhibited high selectivity for CO production up to 84.3% at –0.7 V versus the reversible hydrogen electrode (vs. RHE) and long-term durability over 16 h, which are better than the reported N, P dual-doped carbon catalysts in aqueous media. This work provides a new way to design and fabricate non-metal catalysts for electrocatalysis.
Electroreduction of CO2 into chemicals is of great importance in the global carbon balance. Although noble-metal based catalysts and single-atom catalysts (SACs) are known to be active for CO2 electroreduction reaction (CO2RR), the high cost of noble-metal and the lack of effective synthesis approaches to prepare SACs have tremendously hindered the application. Non-metal doped carbon materials have attracted great interest because of their reasonable cost, chemical stability and excellent electrical conductivity. Nevertheless, the design and fabrication of highly efficient non-metal doped carbon electrocatalysts for CO2RR to meet industry demands still remains a big challenge. Herein, triphenylphosphine@covalent triazine framework (CTF) composites were employed as precursors to fabricate N, P dual-doped porous carbon catalysts PCTF-X-Y (X represents the carbonization temperature, and Y represents the mass ratio of CTF to triphenylphosphine) for CO2RR. Due to the high specific surface areas and synergistic effect between N and P, the obtained PCTF-1000-5 exhibited high selectivity for CO production up to 84.3% at –0.7 V versus the reversible hydrogen electrode (vs. RHE) and long-term durability over 16 h, which are better than the reported N, P dual-doped carbon catalysts in aqueous media. This work provides a new way to design and fabricate non-metal catalysts for electrocatalysis.
2021, 40(9): 1223-1230
doi: 10.14102/j.cnki.0254–5861.2011–3144
Abstract:
Photo-assisted deposited method is often employed in the metal-organic chemical vapor deposition whose ion source is organic compounds. It has been proved to increase the deposition rate and improve the crystallinity of the films. We demonstrate a photo-assisted sputtering deposited method which is used to prepare high quality TiO2 films. The crystallinity of the films is improved by the photo assistance without changing the morphology. And the structural and optical properties remain the same. The photo-assisted deposited TiO2 film shows a H2 evolution rate of 1.62 μmol·cm-2·h-1 that is about twice more than that of the pristine TiO2 film. It is found the Mott-Schottky effect responds for the photocatalytic activity. Photo-assisted deposited films show an enhanced photocatalytic activity due to the reduction of interface recombination and the high efficiency in the transferring of photo-generated carriers.
Photo-assisted deposited method is often employed in the metal-organic chemical vapor deposition whose ion source is organic compounds. It has been proved to increase the deposition rate and improve the crystallinity of the films. We demonstrate a photo-assisted sputtering deposited method which is used to prepare high quality TiO2 films. The crystallinity of the films is improved by the photo assistance without changing the morphology. And the structural and optical properties remain the same. The photo-assisted deposited TiO2 film shows a H2 evolution rate of 1.62 μmol·cm-2·h-1 that is about twice more than that of the pristine TiO2 film. It is found the Mott-Schottky effect responds for the photocatalytic activity. Photo-assisted deposited films show an enhanced photocatalytic activity due to the reduction of interface recombination and the high efficiency in the transferring of photo-generated carriers.
2021, 40(9): 1231-1237
doi: 10.14102/j.cnki.0254–5861.2011–3142
Abstract:
Two novel substituted phenyl isoxazole benzoxazine formamide derivatives were designed and synthesized with substituted o-aminophenol, 1, 2-dibromoethane and different phenyl substituted isoxazole formyl chloride as the raw materials via microwave assistant synthesis. The target compounds were characterized by IR, 1H NMR, 13C NMR and HRMS. Both single-crystal structures were further determined by X-ray diffraction. 3-(2΄-Chloro-6΄-fluoro-phenyl)-4-(2΄, 3΄-dihydro-1΄, 4΄-benzoxazine)-5-methyl-isoxazole formamide (4a) crystallizes in orthorhombic system, P21 space group with a = 8.9414(18), b = 10.834(2), c = 17.706(4) Å, V = 1715.1(6) Å3, Dc = 1.444 Mg/m3, Z = 4, F(000) = 768, μ(MoKα) = 0.255 mm-1, R = 0.0406 and wR = 0.1171. 3-Phenyl-4-(6-methyl-2΄, 3΄-dihydro-1΄, 4΄-benzoxazine)-5-methyl-isoxazole formamide (4b) is of triclinic system, space group P\begin{document}$ \overline 1 $\end{document}
Two novel substituted phenyl isoxazole benzoxazine formamide derivatives were designed and synthesized with substituted o-aminophenol, 1, 2-dibromoethane and different phenyl substituted isoxazole formyl chloride as the raw materials via microwave assistant synthesis. The target compounds were characterized by IR, 1H NMR, 13C NMR and HRMS. Both single-crystal structures were further determined by X-ray diffraction. 3-(2΄-Chloro-6΄-fluoro-phenyl)-4-(2΄, 3΄-dihydro-1΄, 4΄-benzoxazine)-5-methyl-isoxazole formamide (4a) crystallizes in orthorhombic system, P21 space group with a = 8.9414(18), b = 10.834(2), c = 17.706(4) Å, V = 1715.1(6) Å3, Dc = 1.444 Mg/m3, Z = 4, F(000) = 768, μ(MoKα) = 0.255 mm-1, R = 0.0406 and wR = 0.1171. 3-Phenyl-4-(6-methyl-2΄, 3΄-dihydro-1΄, 4΄-benzoxazine)-5-methyl-isoxazole formamide (4b) is of triclinic system, space group P
2021, 40(9): 1238-1245
doi: 10.14102/j.cnki.0254–5861.2011–3124
Abstract:
A stereo-selective palladium-catalyzed one-pot Tsuji-Trost reaction was used to prepare four β-thiogalactosides from unsaturated D-galactal and thiol. Their structures were characterized by nuclear magnetic resonance spectra and high-resolution electrospray ionization mass spectra. The absolute configuration was confirmed with a Flack parameter of 0.019(15) by X-ray crystallography using a Cu radiation source. Compound 6a (C21H24O4S): orthorhombic system, space group P212121, a = 9.0919(4), b = 9.6313(4), c = 22.5936(11) Å, V = 1978.45(15) Å3, Z = 4, F(000) = 792, Dc = 1.250 g/cm3, μ = 1.636 mm−1, R = 0.0478 and wR = 0.1384 for 3621 independent reflections (Rint = 0.0390) and 3326 observed ones (I > 2σ(I)). 3-(4, 5)-Dimethylthiazol-2-yl-2, 5-diphenyltetrazolium bromide (MTT) cell viability assays indicated that these thiogalactosides showed anti-proliferative activities against human gastric cancer HGC-27 cells with IC50 values of 69~88 μM.
A stereo-selective palladium-catalyzed one-pot Tsuji-Trost reaction was used to prepare four β-thiogalactosides from unsaturated D-galactal and thiol. Their structures were characterized by nuclear magnetic resonance spectra and high-resolution electrospray ionization mass spectra. The absolute configuration was confirmed with a Flack parameter of 0.019(15) by X-ray crystallography using a Cu radiation source. Compound 6a (C21H24O4S): orthorhombic system, space group P212121, a = 9.0919(4), b = 9.6313(4), c = 22.5936(11) Å, V = 1978.45(15) Å3, Z = 4, F(000) = 792, Dc = 1.250 g/cm3, μ = 1.636 mm−1, R = 0.0478 and wR = 0.1384 for 3621 independent reflections (Rint = 0.0390) and 3326 observed ones (I > 2σ(I)). 3-(4, 5)-Dimethylthiazol-2-yl-2, 5-diphenyltetrazolium bromide (MTT) cell viability assays indicated that these thiogalactosides showed anti-proliferative activities against human gastric cancer HGC-27 cells with IC50 values of 69~88 μM.
