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2023 Volume 39 Issue 9
2023, 39(9): 1649-1660
doi: 10.11862/CJIC.2023.139
Abstract:
Anthraquinone-based metal-organic cages 1-Zn, 2-Zn and 2-Fe were constructed from ligands L1 and L2 (L1=N2, N7-di((2, 2'-bipyridin)-5-yl)-9, 10-dioxo-9, 10-dihydroanthracene-2, 7-dicarboxamide, L2=N2, N7-bis(4-((2, 2'-bipyridin)-5-yl) phenyl)-9, 10-dioxo-9, 10-dihydroanthracene-2, 7-dicarboxamide) with Zn(Ⅱ) and Fe(Ⅱ) by coordination self-assembly. Single crystal X-ray diffraction and electrospray mass spectrometry showed that this series of complexes were M2L3-type metal-organic structures. The 1-Zn and 2-Zn supramolecular systems were successfully applied to explore the oxidation of toluene into benzaldehyde, and the experiments suggested that the formation of supramolecular host-guest compounds between anthraquinone-based metal-organic cages and toluene was the key to effective oxidation of toluene. The photooxidation performance of 1-Zn and 2-Zn was further investigated by the photooxidation reaction of aromatic alcohols, and the results indicated that the catalytic yields are affected by the electronic effects of the substituents and the size of the substrate molecules.
Anthraquinone-based metal-organic cages 1-Zn, 2-Zn and 2-Fe were constructed from ligands L1 and L2 (L1=N2, N7-di((2, 2'-bipyridin)-5-yl)-9, 10-dioxo-9, 10-dihydroanthracene-2, 7-dicarboxamide, L2=N2, N7-bis(4-((2, 2'-bipyridin)-5-yl) phenyl)-9, 10-dioxo-9, 10-dihydroanthracene-2, 7-dicarboxamide) with Zn(Ⅱ) and Fe(Ⅱ) by coordination self-assembly. Single crystal X-ray diffraction and electrospray mass spectrometry showed that this series of complexes were M2L3-type metal-organic structures. The 1-Zn and 2-Zn supramolecular systems were successfully applied to explore the oxidation of toluene into benzaldehyde, and the experiments suggested that the formation of supramolecular host-guest compounds between anthraquinone-based metal-organic cages and toluene was the key to effective oxidation of toluene. The photooxidation performance of 1-Zn and 2-Zn was further investigated by the photooxidation reaction of aromatic alcohols, and the results indicated that the catalytic yields are affected by the electronic effects of the substituents and the size of the substrate molecules.
2023, 39(9): 1766-1774
doi: 10.11862/CJIC.2023.144
Abstract:
This work reports a simple method to prepare a Si-O-C anode material with a reinforced concrete-like structure, in which carbon nanotubes (CNTs) were embedded and acted like steel bars to provide stress support, and the silicon atoms were wrapped with atomically dispersed carbon and oxygen concrete matrix. An outermost carbon layer was plated via chemical vapor deposition to further inhibit the volume change of the material. Thanks to the unique structural design, the prepared CNTs/SiOx-C/C anode showed excellent electrochemical performance with a high-capacity retention rate of 80% after 970 cycles at 0.5 A·g-1.
This work reports a simple method to prepare a Si-O-C anode material with a reinforced concrete-like structure, in which carbon nanotubes (CNTs) were embedded and acted like steel bars to provide stress support, and the silicon atoms were wrapped with atomically dispersed carbon and oxygen concrete matrix. An outermost carbon layer was plated via chemical vapor deposition to further inhibit the volume change of the material. Thanks to the unique structural design, the prepared CNTs/SiOx-C/C anode showed excellent electrochemical performance with a high-capacity retention rate of 80% after 970 cycles at 0.5 A·g-1.
2023, 39(9): 1775-1781
doi: 10.11862/CJIC.2023.136
Abstract:
Herein, two compounds[NiⅡ (L1)] [FeⅢ (Tp)(CN)3]2·3.5H2O (1) and[NiⅡ (L2)] [FeⅢ (Tp)(CN)3]2·3H2O (2), where Tp=hydrotris(pyrazolyl) borate, L1=3,4-bis(1H-imidazol-1-yl) thiophen, L2=1,2-bis(1H-imidazol-1-yl) thiophen, were successfully synthesized by using isomers with different symmetries to change the intermolecular hydrogen bonding network and manipulate the single-chain magnet behavior. The magnetic performance showed that 1 and 2 displayed single-chain magnet behavior with huge coercive fields of 8.41 and 3.84 kOe, respectively.
Herein, two compounds[NiⅡ (L1)] [FeⅢ (Tp)(CN)3]2·3.5H2O (1) and[NiⅡ (L2)] [FeⅢ (Tp)(CN)3]2·3H2O (2), where Tp=hydrotris(pyrazolyl) borate, L1=3,4-bis(1H-imidazol-1-yl) thiophen, L2=1,2-bis(1H-imidazol-1-yl) thiophen, were successfully synthesized by using isomers with different symmetries to change the intermolecular hydrogen bonding network and manipulate the single-chain magnet behavior. The magnetic performance showed that 1 and 2 displayed single-chain magnet behavior with huge coercive fields of 8.41 and 3.84 kOe, respectively.
2023, 39(9): 1782-1790
doi: 10.11862/CJIC.2023.146
Abstract:
The (1-methyl-1H-benzimidazol-2-yl) methanol (HL) reacted with Zn(NO3)2·6H2O and ZnCl2 in a mixture of methanol and acetonitrile to generate three Zn(Ⅱ) complexes: [Zn(HL)2Cl2] (1), [Zn(HL)2(H2O)2](NO3)2 (2), and [Zn4(L)4Cl4] (3). Their structures were analyzed by elemental analysis, IR, thermogravimetry, and single-crystal X-ray diffraction. The results show that 1 and 2 are mononuclear complexes, and 3 is a tetranuclear complex. The thermogravimetric analysis results show that these complexes had good thermal stability and the structure began to decompose when the temperature exceeded 180 ℃. The fluorescence analysis shows that complexes 1 and 2 had a red shift phenomenon, and when the ligand lost proton H, complex 3 had a significant blue shift phenomenon. The quantum yields of complexes 1, 2, and 3 were 1.00%, 0.78%, and 2.04%, respectively. And the fluorescence lifetimes were 2.306 0, 2.283 6, and 3.039 9 ns, respectively. Therefore, it is possible to enhance the fluorescence lifetime by causing the ligand to lose proton H and form a polynuclear complex.
The (1-methyl-1H-benzimidazol-2-yl) methanol (HL) reacted with Zn(NO3)2·6H2O and ZnCl2 in a mixture of methanol and acetonitrile to generate three Zn(Ⅱ) complexes: [Zn(HL)2Cl2] (1), [Zn(HL)2(H2O)2](NO3)2 (2), and [Zn4(L)4Cl4] (3). Their structures were analyzed by elemental analysis, IR, thermogravimetry, and single-crystal X-ray diffraction. The results show that 1 and 2 are mononuclear complexes, and 3 is a tetranuclear complex. The thermogravimetric analysis results show that these complexes had good thermal stability and the structure began to decompose when the temperature exceeded 180 ℃. The fluorescence analysis shows that complexes 1 and 2 had a red shift phenomenon, and when the ligand lost proton H, complex 3 had a significant blue shift phenomenon. The quantum yields of complexes 1, 2, and 3 were 1.00%, 0.78%, and 2.04%, respectively. And the fluorescence lifetimes were 2.306 0, 2.283 6, and 3.039 9 ns, respectively. Therefore, it is possible to enhance the fluorescence lifetime by causing the ligand to lose proton H and form a polynuclear complex.
2023, 39(9): 1791-1799
doi: 10.11862/CJIC.2023.143
Abstract:
Polyoxometalate(POM)-based supramolecular coordination cages have aroused wide interest in terms of their design and fabrication, however, it still be challenging. Herein, we report a POM-calixarene-based giant[Co8] coordination cage, [Co8(MTR4A)6Cl8](α-SiW12O40)2·30DMF·74EtOH (cage-1), assembled with six bowl-shaped calix[4]resorcinarene(MTR4A) molecules, eight Co (Ⅱ) cations, two α-SiW12O404- counter anions, and eight Cl- anions. Remarkably, α-SiW12O404- anions were sandwiched between layers via hydrogen-bonded to form a 3D supramolecular architecture. Moreover, cage-1 showed a good lithium-ion storage capacity as an anode material in lithium-ion batteries (LIBs). Furthermore, it was shown to be a highly active bifunctional electrocatalytic performance for reducing nitrite (NO2-) and oxidizing ascorbic acid (AA).
Polyoxometalate(POM)-based supramolecular coordination cages have aroused wide interest in terms of their design and fabrication, however, it still be challenging. Herein, we report a POM-calixarene-based giant[Co8] coordination cage, [Co8(MTR4A)6Cl8](α-SiW12O40)2·30DMF·74EtOH (cage-1), assembled with six bowl-shaped calix[4]resorcinarene(MTR4A) molecules, eight Co (Ⅱ) cations, two α-SiW12O404- counter anions, and eight Cl- anions. Remarkably, α-SiW12O404- anions were sandwiched between layers via hydrogen-bonded to form a 3D supramolecular architecture. Moreover, cage-1 showed a good lithium-ion storage capacity as an anode material in lithium-ion batteries (LIBs). Furthermore, it was shown to be a highly active bifunctional electrocatalytic performance for reducing nitrite (NO2-) and oxidizing ascorbic acid (AA).
2023, 39(9): 1800-1806
doi: 10.11862/CJIC.2023.145
Abstract:
We prepared perovskite Ba0.97Ca0.03Sn0.08Ti0.92O3-δ (BCST) with oxygen vacancies as polysulfide (LiPS) immobilizer in Li-S batteries through strong bonding interactions. As a catalyst for promoting LiPS conversion, Ba0.97Ca0.03Sn0.08Ti0.92O3-δ/Ketjen black/sulfur (BCST/KB/S) cathode delivered a high initial specific discharge capacity of 1 164.3 mAh·g-1 and exceptional cycling stability with a low-capacity decay of only 0.052% per cycle over 800 cycles.
We prepared perovskite Ba0.97Ca0.03Sn0.08Ti0.92O3-δ (BCST) with oxygen vacancies as polysulfide (LiPS) immobilizer in Li-S batteries through strong bonding interactions. As a catalyst for promoting LiPS conversion, Ba0.97Ca0.03Sn0.08Ti0.92O3-δ/Ketjen black/sulfur (BCST/KB/S) cathode delivered a high initial specific discharge capacity of 1 164.3 mAh·g-1 and exceptional cycling stability with a low-capacity decay of only 0.052% per cycle over 800 cycles.
2023, 39(9): 1807-1816
doi: 10.11862/CJIC.2023.138
Abstract:
Two binuclear complexes[Pr(2-Cl-4-FBA)3(5,5'-DM-2,2'-bipy)]2 (1) and[Dy(2-Cl-4-FBA)3(5,5'-DM-2,2'-bipy)]2·2(2-Cl-4-FHBA) (2), where 2-Cl-4-FHBA=2-chloro-4-fluorobenzoic acid and 5,5'-DM-2,2'-bipy=5,5'-dimethyl-2,2'-bipyridine, have been fabricated and characterized. The two complexes crystallize in the P1 space group of the triclinic crystal system, featuring 1D and 2D supramolecular structures. The structure of complex 2 is fascinating, containing two free 2-Cl-4-FHBA molecules, which are rare in lanthanide complexes. A three-dimensional infrared stacking diagram of the gas phase products indicates that the main gaseous products released over the whole decomposition process are water, carbon dioxide, some gaseous molecules, and the gaseous organic fragments. Also, the fluorescence property of complex 2 has been studied.
Two binuclear complexes[Pr(2-Cl-4-FBA)3(5,5'-DM-2,2'-bipy)]2 (1) and[Dy(2-Cl-4-FBA)3(5,5'-DM-2,2'-bipy)]2·2(2-Cl-4-FHBA) (2), where 2-Cl-4-FHBA=2-chloro-4-fluorobenzoic acid and 5,5'-DM-2,2'-bipy=5,5'-dimethyl-2,2'-bipyridine, have been fabricated and characterized. The two complexes crystallize in the P1 space group of the triclinic crystal system, featuring 1D and 2D supramolecular structures. The structure of complex 2 is fascinating, containing two free 2-Cl-4-FHBA molecules, which are rare in lanthanide complexes. A three-dimensional infrared stacking diagram of the gas phase products indicates that the main gaseous products released over the whole decomposition process are water, carbon dioxide, some gaseous molecules, and the gaseous organic fragments. Also, the fluorescence property of complex 2 has been studied.
2023, 39(9): 1817-1831
doi: 10.11862/CJIC.2023.142
Abstract:
The development of hydrophobic materials has always been a difficult issue in the protection of stone cultural relics. In this work, a new hydrophobic metal-organic framework material was synthesized by modifying the Zr-based MOFs containing 2-hydroxyterephthalic acid linkers with fluorosilane to obtain UIO-O-FS material, and characterization tests such as FTIR, X-ray diffraction, N2 adsorption-desorption, thermogravimetry, scanning electron microscope, and transmission electron microscope, as well as erosion resistance tests, were carried out on the material. Based on the results, the material possesses good hydrophobicity, consolidation ability, acid resistance, and salt resistance, and is a new type of stone heritage conservation material.
The development of hydrophobic materials has always been a difficult issue in the protection of stone cultural relics. In this work, a new hydrophobic metal-organic framework material was synthesized by modifying the Zr-based MOFs containing 2-hydroxyterephthalic acid linkers with fluorosilane to obtain UIO-O-FS material, and characterization tests such as FTIR, X-ray diffraction, N2 adsorption-desorption, thermogravimetry, scanning electron microscope, and transmission electron microscope, as well as erosion resistance tests, were carried out on the material. Based on the results, the material possesses good hydrophobicity, consolidation ability, acid resistance, and salt resistance, and is a new type of stone heritage conservation material.
2023, 39(9): 1832-1840
doi: 10.11862/CJIC.2023.140
Abstract:
A new fluorescent probe metal-organic framework (MOF) materials formulated as [Cd(PLIA)(TIB)]n(MOF-1) was successfully obtained adopting 5-((4-pyridyl)methoxy)-isophthalic acid (H2PLIA) and 1, 3, 5-tris(1-imidazolyl)-benzene (TIB). MOF-1 possesses 2D networks with an ideal 1D tunnel, and the 1D tunnel is spaced and driven by the flexible triangle PLIA2- and rigid triangle TIB ligands. Employing the advantage of MOF-1 channel easy doping, efficient luminescent probe Tb@MOF-1 was also constructed using a coordinated post-synthetic modification strategy. MOF-1 and Tb@MOF-1 were fully characterized in detail, and the two probe materials have the same structural feature. The fluorescence recognition performance was investigated in detail, revealing a capability of MOF-1 for sensing Cr2O72-, Tb@MOF-1 for identifying S2O82- anion. Herein, the fabricated fluorescent probes exhibit fascinating features, such as fast response time, remarkable stability, excellent selectivity, and high sensitivity. The possible fluorescence recognition mechanism of Cr2O72- and S2O82- by MOF-1 and Tb@MOF-1 has been investigated, and the difference in the mechanism may be related to Tb3+ ion doping.
A new fluorescent probe metal-organic framework (MOF) materials formulated as [Cd(PLIA)(TIB)]n(MOF-1) was successfully obtained adopting 5-((4-pyridyl)methoxy)-isophthalic acid (H2PLIA) and 1, 3, 5-tris(1-imidazolyl)-benzene (TIB). MOF-1 possesses 2D networks with an ideal 1D tunnel, and the 1D tunnel is spaced and driven by the flexible triangle PLIA2- and rigid triangle TIB ligands. Employing the advantage of MOF-1 channel easy doping, efficient luminescent probe Tb@MOF-1 was also constructed using a coordinated post-synthetic modification strategy. MOF-1 and Tb@MOF-1 were fully characterized in detail, and the two probe materials have the same structural feature. The fluorescence recognition performance was investigated in detail, revealing a capability of MOF-1 for sensing Cr2O72-, Tb@MOF-1 for identifying S2O82- anion. Herein, the fabricated fluorescent probes exhibit fascinating features, such as fast response time, remarkable stability, excellent selectivity, and high sensitivity. The possible fluorescence recognition mechanism of Cr2O72- and S2O82- by MOF-1 and Tb@MOF-1 has been investigated, and the difference in the mechanism may be related to Tb3+ ion doping.
2023, 39(9): 1661-1672
doi: 10.11862/CJIC.2023.130
Abstract:
This paper proposes a scheme of recycling spent batteries, using concentrated hydrochloric acid as leaching agent, NaOH and NH4HCO3 as precipitating agents. The oxidation reaction of Mn2+ under alkaline conditions was included to change the precipitation order of ions, thus recovered ions in steps. The optimal conditions for acid leaching of concentrated hydrochloric acid to treat the ternary cathode material LiNi0.8Co0.05Mn0.15O2 were studied. In the stepwise precipitation process, Mn2+ was oxidized to MnO(OH)2, which is insoluble in non-reducing acids, and then Mn was recovered under acidic conditions. While Ni and Co were recovered under alkaline conditions by using NaOH. Li was recovered by using NH4HCO3. Using this method, the recovery of Mn reached 85.1% and the product purity reached 98.6%; the recovery of Li reached 95.0% and the product purity reached 99.3%. The pouch cell assembled with the re-synthesized ternary cathode using the recovered material reached a discharge specific capacity of 175 mAh·g-1 in the first cycle. It could stably cycle for 50 cycles with Coulombic efficiency of over 99.5%.
This paper proposes a scheme of recycling spent batteries, using concentrated hydrochloric acid as leaching agent, NaOH and NH4HCO3 as precipitating agents. The oxidation reaction of Mn2+ under alkaline conditions was included to change the precipitation order of ions, thus recovered ions in steps. The optimal conditions for acid leaching of concentrated hydrochloric acid to treat the ternary cathode material LiNi0.8Co0.05Mn0.15O2 were studied. In the stepwise precipitation process, Mn2+ was oxidized to MnO(OH)2, which is insoluble in non-reducing acids, and then Mn was recovered under acidic conditions. While Ni and Co were recovered under alkaline conditions by using NaOH. Li was recovered by using NH4HCO3. Using this method, the recovery of Mn reached 85.1% and the product purity reached 98.6%; the recovery of Li reached 95.0% and the product purity reached 99.3%. The pouch cell assembled with the re-synthesized ternary cathode using the recovered material reached a discharge specific capacity of 175 mAh·g-1 in the first cycle. It could stably cycle for 50 cycles with Coulombic efficiency of over 99.5%.
2023, 39(9): 1673-1681
doi: 10.11862/CJIC.2023.141
Abstract:
Carboxyl functionalized terbium fluorescent nanocomplex was chemically synthesized by a one-step process using terbium ion as the luminescence center, p-phthalic acid as the first ligand, and phenanthroline as the second ligand. The carboxyl groups on the surface of these nanocomplexes were further activated using 1-(3-dimethyl-amino-propyl)-3-ethylcarbodiimine hydrochloride as the activator combined with N-hydroxy succinimide as the stabilizer. Due to the rapid and mild amide reaction between the activated carboxyl groups on the surface of the nano-complexes and the amino groups in bloody fingerprint residuals, the resulting nanocomplexes were finally used as fluorescent probes for the targeted development of latent bloody fingerprints. Excited with 254 nm ultraviolet light, the papillary ridges could emit strong green fluorescence, which could give a sufficient contrast between the developing signal and the background noise; the papillary ridges were coherent, the minutiae were sharp, and the sweat pores were distinct; the contrast between the ridges and the furrows were obvious. The parameters for fingerprint development were optimized, namely, the mass ratio of nanocomplex to water in suspension was recommended to be 1:35, and the period for staining was recommended to be 20 s. In addition, the contrast, sensitivity, selectivity, and applicability in fingerprint development were also investigated in detail. Experimental results show that the activated carboxyl functionalized terbium fluorescent nanocomplexes are suitable for developing the latent bloody fingerprints on smooth non- and semi-porous surfaces with high quality and high efficiency.
Carboxyl functionalized terbium fluorescent nanocomplex was chemically synthesized by a one-step process using terbium ion as the luminescence center, p-phthalic acid as the first ligand, and phenanthroline as the second ligand. The carboxyl groups on the surface of these nanocomplexes were further activated using 1-(3-dimethyl-amino-propyl)-3-ethylcarbodiimine hydrochloride as the activator combined with N-hydroxy succinimide as the stabilizer. Due to the rapid and mild amide reaction between the activated carboxyl groups on the surface of the nano-complexes and the amino groups in bloody fingerprint residuals, the resulting nanocomplexes were finally used as fluorescent probes for the targeted development of latent bloody fingerprints. Excited with 254 nm ultraviolet light, the papillary ridges could emit strong green fluorescence, which could give a sufficient contrast between the developing signal and the background noise; the papillary ridges were coherent, the minutiae were sharp, and the sweat pores were distinct; the contrast between the ridges and the furrows were obvious. The parameters for fingerprint development were optimized, namely, the mass ratio of nanocomplex to water in suspension was recommended to be 1:35, and the period for staining was recommended to be 20 s. In addition, the contrast, sensitivity, selectivity, and applicability in fingerprint development were also investigated in detail. Experimental results show that the activated carboxyl functionalized terbium fluorescent nanocomplexes are suitable for developing the latent bloody fingerprints on smooth non- and semi-porous surfaces with high quality and high efficiency.
2023, 39(9): 1682-1690
doi: 10.11862/CJIC.2023.113
Abstract:
Herein, Au/CeO2 was synthesized to study the morphological effect on the behavior construction of strong metal-support interaction (SMSI). Different morphologies of CeO2, such as nanocube and nanorod, were selected as catalytic support. A series of characterization including high resolution (scanning) transmission electron microscopy, X-ray photoelectron spectroscopy, hydrogen temperature programmed reduction (H2-TPR) and so on, revealed that the mass transfer on nanocube was occurred more easily and the CeO2-x coating on the surface of nanocubes was thicker than nanorod. The CeO2-x coating resulted that the adsorption of small molecules decreased significantly and catalytic active sites were hidden. The influence on probe reaction (selective catalytic hydrogenation activity of butadiene) could be observed clearly. Therefore, the CeO2 nanocube was more facile undergo Au-CeO2 SMSI than the nanorod.
Herein, Au/CeO2 was synthesized to study the morphological effect on the behavior construction of strong metal-support interaction (SMSI). Different morphologies of CeO2, such as nanocube and nanorod, were selected as catalytic support. A series of characterization including high resolution (scanning) transmission electron microscopy, X-ray photoelectron spectroscopy, hydrogen temperature programmed reduction (H2-TPR) and so on, revealed that the mass transfer on nanocube was occurred more easily and the CeO2-x coating on the surface of nanocubes was thicker than nanorod. The CeO2-x coating resulted that the adsorption of small molecules decreased significantly and catalytic active sites were hidden. The influence on probe reaction (selective catalytic hydrogenation activity of butadiene) could be observed clearly. Therefore, the CeO2 nanocube was more facile undergo Au-CeO2 SMSI than the nanorod.
2023, 39(9): 1691-1698
doi: 10.11862/CJIC.2023.123
Abstract:
To develop covalent organic frameworks supercapacitors electrode materials, functional designs is important practical significance to enhance electrochemical performance. Two-dimensional covalent organic frameworks (COFs) based on Ni-Salphen (Ni-Salphen-COF) has been constructed by the reaction of 2, 3, 6, 7, 10, 11-hexaaminotri-phenylene (HATP) and 4, 6-dihydroxy-5-methyl-1, 3-diformyl benzene (DMDB). Structures, morphology, and electro-chemical properties of the Ni-Salphen-COF were characterized via a series of methods. The three-electrode test results suggest that Ni-Salphen-COF showed excellent specific capacitance of 531 F·g-1 and good cycle stability (capacity retention of 89% after 10 000 cycles) at the current density of 1 A·g-1. Meanwhile, Ni-Salphen-COF//AC (AC: activated carbon) in the two-electrode system displayed the specific capacitance of 176 F·g-1 at 1 A·g-1, and the highest energy density was up to 55 Wh·kg-1 at a power density of 900 W·kg-1. Compared to Salphen-COF with-out Ni, Ni-Salphen-COF showed a high specific capacitance. The electrochemical performance could be attributed to Ni-Salphen units, increasing in electrical conductivity, redox-active, and charge transfer activity.
To develop covalent organic frameworks supercapacitors electrode materials, functional designs is important practical significance to enhance electrochemical performance. Two-dimensional covalent organic frameworks (COFs) based on Ni-Salphen (Ni-Salphen-COF) has been constructed by the reaction of 2, 3, 6, 7, 10, 11-hexaaminotri-phenylene (HATP) and 4, 6-dihydroxy-5-methyl-1, 3-diformyl benzene (DMDB). Structures, morphology, and electro-chemical properties of the Ni-Salphen-COF were characterized via a series of methods. The three-electrode test results suggest that Ni-Salphen-COF showed excellent specific capacitance of 531 F·g-1 and good cycle stability (capacity retention of 89% after 10 000 cycles) at the current density of 1 A·g-1. Meanwhile, Ni-Salphen-COF//AC (AC: activated carbon) in the two-electrode system displayed the specific capacitance of 176 F·g-1 at 1 A·g-1, and the highest energy density was up to 55 Wh·kg-1 at a power density of 900 W·kg-1. Compared to Salphen-COF with-out Ni, Ni-Salphen-COF showed a high specific capacitance. The electrochemical performance could be attributed to Ni-Salphen units, increasing in electrical conductivity, redox-active, and charge transfer activity.
2023, 39(9): 1699-1710
doi: 10.11862/CJIC.2023.131
Abstract:
Al2O3-CeO2composite was prepared by coprecipitation method and used as electrolytes in semiconductor ionic fuel cells (SIFCs). We investigated the impact of Al2O3-CeO2 composite electrolyte with different molar ratio of Al2O3 and CeO2 on the electrochemical performance of fuel cells. The composites were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) techniques. Among the composites, the obtained Al2O3-CeO2 when the molar ratio was 1∶0.5 exhibited the best performance, and its maximum power density was 1 142 mW·cm-2 when the open-circuit voltage was 1.099 V at 550 ℃. Furthermore, the Al2O3-CeO2 cell displayed excellent mixed ionic conduction and power output performance due to the interface effect of the composite material as the fuel cell electrolyte in the test atmosphere.
Al2O3-CeO2composite was prepared by coprecipitation method and used as electrolytes in semiconductor ionic fuel cells (SIFCs). We investigated the impact of Al2O3-CeO2 composite electrolyte with different molar ratio of Al2O3 and CeO2 on the electrochemical performance of fuel cells. The composites were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) techniques. Among the composites, the obtained Al2O3-CeO2 when the molar ratio was 1∶0.5 exhibited the best performance, and its maximum power density was 1 142 mW·cm-2 when the open-circuit voltage was 1.099 V at 550 ℃. Furthermore, the Al2O3-CeO2 cell displayed excellent mixed ionic conduction and power output performance due to the interface effect of the composite material as the fuel cell electrolyte in the test atmosphere.
2023, 39(9): 1711-1720
doi: 10.11862/CJIC.2023.122
Abstract:
By introducing 2, 7-naphthalene disulfonic acid (H2NDA) as a structure-directed agent, four new Q[5]-based supramolecular self-assemblies, namely[K2(H2O)4(Q[5])](2, 7-NDA)·4H2O (1), [Rb2(H2O)5(Q[5])](2, 7-NDA)· 3H2O (2), [Mg(H2O)4(Q[5])](2, 7-NDA)·8H2O (3), and[Ca(H2O)4(Q[5])](2, 7-NDA)·10H2O (4), were prepared under hydrothermal conditions. Single crystal X-ray diffraction results show that the self-assemblies 1 and 2 have the same structure. The coordination of the Q[5] molecule with metal ions forms a "molecular capsule" structure in 1 and 2, while the coordination of Q[5] and Mg2+ in 3 forms a 1:1 simple complex structure. In 4, Q[5] and Ca2+ can directly coordinate to form a 1D Q[5]-Ca2+coordination polymer chain structure. The 2, 7-NDA2- anions in these structures balance the system charge, and through their outer-surface interactions with Q[5], promote its final construction into a 3D supramolecular structure. In addition, we also studied the fluorescence sensing properties of self-assembly 4, which could be used as quenching fluorescence probes for the organic solvents acetone and DMF.
By introducing 2, 7-naphthalene disulfonic acid (H2NDA) as a structure-directed agent, four new Q[5]-based supramolecular self-assemblies, namely[K2(H2O)4(Q[5])](2, 7-NDA)·4H2O (1), [Rb2(H2O)5(Q[5])](2, 7-NDA)· 3H2O (2), [Mg(H2O)4(Q[5])](2, 7-NDA)·8H2O (3), and[Ca(H2O)4(Q[5])](2, 7-NDA)·10H2O (4), were prepared under hydrothermal conditions. Single crystal X-ray diffraction results show that the self-assemblies 1 and 2 have the same structure. The coordination of the Q[5] molecule with metal ions forms a "molecular capsule" structure in 1 and 2, while the coordination of Q[5] and Mg2+ in 3 forms a 1:1 simple complex structure. In 4, Q[5] and Ca2+ can directly coordinate to form a 1D Q[5]-Ca2+coordination polymer chain structure. The 2, 7-NDA2- anions in these structures balance the system charge, and through their outer-surface interactions with Q[5], promote its final construction into a 3D supramolecular structure. In addition, we also studied the fluorescence sensing properties of self-assembly 4, which could be used as quenching fluorescence probes for the organic solvents acetone and DMF.
2023, 39(9): 1721-1728
doi: 10.11862/CJIC.2023.134
Abstract:
The stability, electronic structure, work function, and optical properties of monolayer GaN, g-C3N4, GaN/g-C3N4 heterojunctions and three nitrogen-deficient GaN/g-C3N4-VXN (X=1, 2, 3) heterojunctions were investigated based on the first-principles plane wave super-soft pseudopotential method under density generalized theory. The calculated results show that the lattice mismatch rate of the GaN/g-C3N4 heterojunction is extremely low (0.8%) and is a complete co-lattice. Compared with monolayer g-C3N4, the conduction bands of the GaN/g-C3N4 and GaN/g-C3N4-VXN (X=1, 2, 3) heterojunctions are shifted in the low-energy direction and the valence bands are shifted upward, which leads to the reduction of the band gap, and the density of states all show orbital hybridization. The GaN/g-C3N4 and GaN/g-C3N4-VXN (X=1, 2, 3) heterojunctions all form a potential difference at the interface, forming the built-in electric fields from the g-C3N4 layer to the GaN layer. The GaN/g-C3N4-V1N heterojunction has the largest interfacial potential difference and the most obvious red-shift phenomenon, indicating that the GaN/g-C3N4-V1N heterojunction has the best optical performance compared to the other two N-defective heterojunctions. The introduction of nitrogen vacancies improves the light absorption ability of GaN/g-C3N4 heterojunction in the infrared region to different degrees.
The stability, electronic structure, work function, and optical properties of monolayer GaN, g-C3N4, GaN/g-C3N4 heterojunctions and three nitrogen-deficient GaN/g-C3N4-VXN (X=1, 2, 3) heterojunctions were investigated based on the first-principles plane wave super-soft pseudopotential method under density generalized theory. The calculated results show that the lattice mismatch rate of the GaN/g-C3N4 heterojunction is extremely low (0.8%) and is a complete co-lattice. Compared with monolayer g-C3N4, the conduction bands of the GaN/g-C3N4 and GaN/g-C3N4-VXN (X=1, 2, 3) heterojunctions are shifted in the low-energy direction and the valence bands are shifted upward, which leads to the reduction of the band gap, and the density of states all show orbital hybridization. The GaN/g-C3N4 and GaN/g-C3N4-VXN (X=1, 2, 3) heterojunctions all form a potential difference at the interface, forming the built-in electric fields from the g-C3N4 layer to the GaN layer. The GaN/g-C3N4-V1N heterojunction has the largest interfacial potential difference and the most obvious red-shift phenomenon, indicating that the GaN/g-C3N4-V1N heterojunction has the best optical performance compared to the other two N-defective heterojunctions. The introduction of nitrogen vacancies improves the light absorption ability of GaN/g-C3N4 heterojunction in the infrared region to different degrees.
2023, 39(9): 1729-1737
doi: 10.11862/CJIC.2023.132
Abstract:
Using medical gauze (MG) as both template and reductant, MG templated manganese dioxide nanoparticle (MnO2 NPs/MG) was facilely synthesized through an in situ redox reaction. The morphology and composition were characterized. MnO2 NPs were evenly loaded and dispersed on the surface of MG fibers. Combing the adsorption property of MnO2 NPs with ease of operation of MG, MnO2 NPs/MG were further applied to the removal of methylene blue. The results indicated that, by simple soaking and stirring under neutral conditions, the removal efficiency can reach 85.09%, and it can be improved by increasing the ratio of adsorption material dosage to the initial amount of dye. Through isothermal adsorption and kinetic studies, it was proved that the adsorption of methylene blue by MnO2 NPs/MG conformed to Langmuir adsorption isothermal model and pseudo-second-order kinetic model.
Using medical gauze (MG) as both template and reductant, MG templated manganese dioxide nanoparticle (MnO2 NPs/MG) was facilely synthesized through an in situ redox reaction. The morphology and composition were characterized. MnO2 NPs were evenly loaded and dispersed on the surface of MG fibers. Combing the adsorption property of MnO2 NPs with ease of operation of MG, MnO2 NPs/MG were further applied to the removal of methylene blue. The results indicated that, by simple soaking and stirring under neutral conditions, the removal efficiency can reach 85.09%, and it can be improved by increasing the ratio of adsorption material dosage to the initial amount of dye. Through isothermal adsorption and kinetic studies, it was proved that the adsorption of methylene blue by MnO2 NPs/MG conformed to Langmuir adsorption isothermal model and pseudo-second-order kinetic model.
2023, 39(9): 1738-1750
doi: 10.11862/CJIC.2023.129
Abstract:
The low-cost supported nickel nanoparticle catalysts Ni-Co@C-N were prepared with ZIF-67 as a precursor by pyrolysis and then ethylene glycol reduction. The characterization results of X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), and X-ray photoelectron spectroscopy (XPS) indicated the successful preparation of supported nickel nanoparticle catalysts Ni-Co@C-N, Ni and Co nanoparticles uniformly dispersed. Weak bases such as Na2CO3 and low molecular weight PVPk18 dispersants contribute to the loading of Ni nanoparticles. The results of N2 adsorption-desorption indicated that the specific surface areas of the Ni-Co@C-N materials were between 107 and 211 m2·g-1, and the average pore widths were between 7.4 and 11.2 nm. The catalytic performance of the Ni-Co@C-N catalysts for the synthesis of nitroaromatic compounds into the corresponding oxide azobenzene compounds was studied, and the effects of the types of alkali and dispersant on the structure and properties of catalysts were also discussed. The results demonstrated that the alkaline enhancement accelerated the nucleation rate of nanoparticles while increasing the molecular weight of dispersants limited the size growth of nanoparticles. Among them, Ni-Co@C-N-4 prepared by the weak base and low molecular weight dispersant possessed the best catalytic performance, the conversion rate and yield of raw materials reached 92.8% and 89.3% respectively after 30 min of reaction, and the cycle test showed that Ni-Co@C-N-4 had good stability.
The low-cost supported nickel nanoparticle catalysts Ni-Co@C-N were prepared with ZIF-67 as a precursor by pyrolysis and then ethylene glycol reduction. The characterization results of X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), and X-ray photoelectron spectroscopy (XPS) indicated the successful preparation of supported nickel nanoparticle catalysts Ni-Co@C-N, Ni and Co nanoparticles uniformly dispersed. Weak bases such as Na2CO3 and low molecular weight PVPk18 dispersants contribute to the loading of Ni nanoparticles. The results of N2 adsorption-desorption indicated that the specific surface areas of the Ni-Co@C-N materials were between 107 and 211 m2·g-1, and the average pore widths were between 7.4 and 11.2 nm. The catalytic performance of the Ni-Co@C-N catalysts for the synthesis of nitroaromatic compounds into the corresponding oxide azobenzene compounds was studied, and the effects of the types of alkali and dispersant on the structure and properties of catalysts were also discussed. The results demonstrated that the alkaline enhancement accelerated the nucleation rate of nanoparticles while increasing the molecular weight of dispersants limited the size growth of nanoparticles. Among them, Ni-Co@C-N-4 prepared by the weak base and low molecular weight dispersant possessed the best catalytic performance, the conversion rate and yield of raw materials reached 92.8% and 89.3% respectively after 30 min of reaction, and the cycle test showed that Ni-Co@C-N-4 had good stability.
2023, 39(9): 1751-1756
doi: 10.11862/CJIC.2023.137
Abstract:
A novel white light metal-organic framework (Me4N)3[Mn3(btc)2(Hbtc)(CH3COO)]·7CH3OH (1) was prepared by a solvothermal method using 1,3,5-benzenetricarboxylic acid (H3btc) and MnCl2·4H2O. The compound was characterized by single-crystal X-ray diffraction and infrared spectrum, and its thermal stability and white fluorescence properties were studied. The results show that compound 1 emitted red light, white light, and blue light at 287, 355, and 375 nm, respectively. The emissions of the organic ligands H3btc (390 nm) may be ascribed to the π→π* or π*→n transitions. Compound 1 showed dual-modal emission at 455 and 675 nm (λex=355 nm) and showed a red shift compared to H3btc, which may be the result of ligand-to-metal charge transfer (LMCT). The CIE chromaticity coordinates were used to visualize the emission spectrum, and the white chromaticity coordinates were (0.286, 0.256).
A novel white light metal-organic framework (Me4N)3[Mn3(btc)2(Hbtc)(CH3COO)]·7CH3OH (1) was prepared by a solvothermal method using 1,3,5-benzenetricarboxylic acid (H3btc) and MnCl2·4H2O. The compound was characterized by single-crystal X-ray diffraction and infrared spectrum, and its thermal stability and white fluorescence properties were studied. The results show that compound 1 emitted red light, white light, and blue light at 287, 355, and 375 nm, respectively. The emissions of the organic ligands H3btc (390 nm) may be ascribed to the π→π* or π*→n transitions. Compound 1 showed dual-modal emission at 455 and 675 nm (λex=355 nm) and showed a red shift compared to H3btc, which may be the result of ligand-to-metal charge transfer (LMCT). The CIE chromaticity coordinates were used to visualize the emission spectrum, and the white chromaticity coordinates were (0.286, 0.256).
2023, 39(9): 1757-1765
doi: 10.11862/CJIC.2023.135
Abstract:
In this work, a novel polymethyl methacrylate-coated MAPbBr3 nanocrystalline (MAPbBr3@PMMA, MA=methylammonium) electrospinning film was synthesized by in situ growth method, and NH3 sensor was constructed based on the fluorescence significant quenching of the MAPbBr3@PMMA electrospinning film after the addition of NH3 gas. The morphology and structure of MAPbBr3@PMMA fiber were characterized by scanning electron microscopy, transmission electron microscopy, powder X-ray diffraction, and infrared spectroscopy, and its optical properties were characterized by UV-Vis and fluorescence spectroscopy. The results showed that the prepared NH3 sensor showed a good linear relationship (r=0.995 9) to NH3 gas concentration in a range of 8-90 mg·L-1, low detection limit (3 mg·L-1), and high reproducibility and selectivity. Finally, the standard recovery and the relative standard deviation (RSD) for NH3 of actual sample gas were 92.2%-102.1% and 1.8%-3.2%, respectively.
In this work, a novel polymethyl methacrylate-coated MAPbBr3 nanocrystalline (MAPbBr3@PMMA, MA=methylammonium) electrospinning film was synthesized by in situ growth method, and NH3 sensor was constructed based on the fluorescence significant quenching of the MAPbBr3@PMMA electrospinning film after the addition of NH3 gas. The morphology and structure of MAPbBr3@PMMA fiber were characterized by scanning electron microscopy, transmission electron microscopy, powder X-ray diffraction, and infrared spectroscopy, and its optical properties were characterized by UV-Vis and fluorescence spectroscopy. The results showed that the prepared NH3 sensor showed a good linear relationship (r=0.995 9) to NH3 gas concentration in a range of 8-90 mg·L-1, low detection limit (3 mg·L-1), and high reproducibility and selectivity. Finally, the standard recovery and the relative standard deviation (RSD) for NH3 of actual sample gas were 92.2%-102.1% and 1.8%-3.2%, respectively.
