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2021 Volume 37 Issue 8
2021, 37(8): 1345-1352
doi: 10.11862/CJIC.2021.171
Abstract:
It is of great importance for studying the value of various cultural heritages to well understand the development history of human society. However, the cultural heritages are destroyed because of environmental changes and the passage of time. Thus, this work mainly focuses on summarizing the studies on different inorganic nanomaterials and their composites for the restoration and protection of cultural heritages, such as nano calcium hydroxide ((OH)2), titanium dioxide (TiO2) and silicon dioxide (SiO2), as well as make a summary and outlook on the further development of such materials in future.
It is of great importance for studying the value of various cultural heritages to well understand the development history of human society. However, the cultural heritages are destroyed because of environmental changes and the passage of time. Thus, this work mainly focuses on summarizing the studies on different inorganic nanomaterials and their composites for the restoration and protection of cultural heritages, such as nano calcium hydroxide ((OH)2), titanium dioxide (TiO2) and silicon dioxide (SiO2), as well as make a summary and outlook on the further development of such materials in future.
2021, 37(8): 1353-1363
doi: 10.11862/CJIC.2021.160
Abstract:
Perovskite oxides have attracted much attention in the field of microwave absorption due to their unique structure and high thermal stability. The most common way to adjust the electromagnetic properties is to add different ions into the perovskite structure, but there is disadvantage study of structure changes before and after doping, and the relationship between the structure changes and electromagnetic absorption characteristics. Based on this, the research progress of perovskite Mn oxide, Co oxide, Fe oxide materials is analyzed in detail from the rule of electromagnetic wave absorption properties which vary with the change of magnetism and conductivity, which is due to the distortion effect caused by the change of perovskite structure and the double exchange of free electrons caused by the change of ionic valence state in the crystal. The structure and microwave absorption mechanism of perovskite oxides are introduced, and the existing problems and future development direction are pointed out.
Perovskite oxides have attracted much attention in the field of microwave absorption due to their unique structure and high thermal stability. The most common way to adjust the electromagnetic properties is to add different ions into the perovskite structure, but there is disadvantage study of structure changes before and after doping, and the relationship between the structure changes and electromagnetic absorption characteristics. Based on this, the research progress of perovskite Mn oxide, Co oxide, Fe oxide materials is analyzed in detail from the rule of electromagnetic wave absorption properties which vary with the change of magnetism and conductivity, which is due to the distortion effect caused by the change of perovskite structure and the double exchange of free electrons caused by the change of ionic valence state in the crystal. The structure and microwave absorption mechanism of perovskite oxides are introduced, and the existing problems and future development direction are pointed out.
2021, 37(8): 1364-1374
doi: 10.11862/CJIC.2021.165
Abstract:
Three new coordination polymers, namely, {[Mn3(oba)3(bib) (DMF) (H2O)]·DMF}n (1), [Co(Hoba)2(bib)]n (2), {[Co(aip) (bib)]·DMF}n (3) (bib=1, 4-bis(imidazol-1-yl) benzene, H2oba=4, 4'-oxybisbenzoic acid, H2aip=5-aminoisophthalic acid, DMF=N, N-dimethylformamide) have been solvothermal synthesized and structurally characterized by elemental analysis, FT-IR spectroscopy, UV-Vis spectroscopy, thermogravimetric analysis, single crystal X-ray crystallography and powder X-ray diffraction. Compound 1 reveals a 3D porous metal-organic framework with the point symbol of {318; 437; 524; 612}{39; 412; 52; 63; 72}{39; 412; 53; 64}. Compound 2 exhibits a 1D chain structure and the neigh-boring chains are further linked by hydrogen-bond O—H…O interactions to form a 3D supramolecular structure with the point symbol of {10}{8;104; 14}{83}2. Compound 3 has a 2D layer structure, which are joined together by hydrogen-bond N—H…O interactions to form a 3D network with the point symbol of {33; 410; 5;6}. Compound 1 shows rapid and selective adsorption of Congo red (CR) from dye mixtures, while compounds 2 and 3 display weak antifer-romagnetic interaction between the Co(Ⅱ) centers.
Three new coordination polymers, namely, {[Mn3(oba)3(bib) (DMF) (H2O)]·DMF}n (1), [Co(Hoba)2(bib)]n (2), {[Co(aip) (bib)]·DMF}n (3) (bib=1, 4-bis(imidazol-1-yl) benzene, H2oba=4, 4'-oxybisbenzoic acid, H2aip=5-aminoisophthalic acid, DMF=N, N-dimethylformamide) have been solvothermal synthesized and structurally characterized by elemental analysis, FT-IR spectroscopy, UV-Vis spectroscopy, thermogravimetric analysis, single crystal X-ray crystallography and powder X-ray diffraction. Compound 1 reveals a 3D porous metal-organic framework with the point symbol of {318; 437; 524; 612}{39; 412; 52; 63; 72}{39; 412; 53; 64}. Compound 2 exhibits a 1D chain structure and the neigh-boring chains are further linked by hydrogen-bond O—H…O interactions to form a 3D supramolecular structure with the point symbol of {10}{8;104; 14}{83}2. Compound 3 has a 2D layer structure, which are joined together by hydrogen-bond N—H…O interactions to form a 3D network with the point symbol of {33; 410; 5;6}. Compound 1 shows rapid and selective adsorption of Congo red (CR) from dye mixtures, while compounds 2 and 3 display weak antifer-romagnetic interaction between the Co(Ⅱ) centers.
2021, 37(8): 1439-1448
doi: 10.11862/CJIC.2021.164
Abstract:
Holey ultrathin g-C3N4 nanosheets (CNHS) were prepared by thermal oxidation etching method with melamine as the precursor, and Pt-CNHS photocatalyst was synthesized via a facile in-situ photochemical reduction of CNHS and K2PtCl6. The X-ray diffraction, field emission scanning electron microscope, X-ray photoelectron spectroscopy, transmission electron microscope, UV-Vis diffuse reflection spectroscopy and N2 adsorption-desorption measurements were used to investigate the structure, morphology, optical absorption characteristics, photoelectrochemical properties and specific surface area of the products. The photocatalytic performance of the catalyst was studied by degrading gaseous toluene under UV and visible light. The results show that the introduction of Pt can effectively enhance the visible light absorption capacity, response range and carrier separation efficiency of the catalyst. Compared with bulk g-C3N4 (CNB) and CNHS, the Pt-CNHS composite displayed much higher photocatalytic activities in gaseous toluene degradation under UV-and visible-light irradiation. In addition, a preliminary study was made on the reaction process of Pt-CNHS photocatalyst to degrade gaseous toluene under visible light.
Holey ultrathin g-C3N4 nanosheets (CNHS) were prepared by thermal oxidation etching method with melamine as the precursor, and Pt-CNHS photocatalyst was synthesized via a facile in-situ photochemical reduction of CNHS and K2PtCl6. The X-ray diffraction, field emission scanning electron microscope, X-ray photoelectron spectroscopy, transmission electron microscope, UV-Vis diffuse reflection spectroscopy and N2 adsorption-desorption measurements were used to investigate the structure, morphology, optical absorption characteristics, photoelectrochemical properties and specific surface area of the products. The photocatalytic performance of the catalyst was studied by degrading gaseous toluene under UV and visible light. The results show that the introduction of Pt can effectively enhance the visible light absorption capacity, response range and carrier separation efficiency of the catalyst. Compared with bulk g-C3N4 (CNB) and CNHS, the Pt-CNHS composite displayed much higher photocatalytic activities in gaseous toluene degradation under UV-and visible-light irradiation. In addition, a preliminary study was made on the reaction process of Pt-CNHS photocatalyst to degrade gaseous toluene under visible light.
2021, 37(8): 1449-1456
doi: 10.11862/CJIC.2021.170
Abstract:
In the absence/presence of chelating N ancillary ligand, 2, 2'-bipyridine (2, 2'-bpy), treatment of 5-methyl-1H-pyrazole-3-carboxylic acid (H2MPCA) with corresponding Mn(Ⅱ)/Ni(Ⅱ) metal salts afforded two complexes, [Mn(HMPCA)2(H2O)2] (1) and[Ni(HMPCA)2(2, 2'-bpy)]·2H2O (2). In mononuclear complexes 1 and 2, each metal ion locates in a distorted octahedral geometry, and the HMPCA-ligands in 1 and 2 both act as a N, O-chelating ligand. In 1, by the function of intermolecular N—H…O and O—H…O hydrogen bonds, the independent[Mn(HMPCA)2 (H2O)2] units are packed into a porous 3D supramolecular structure with 1D nanotube. In 2, the mononuclear components[Ni(HMPCA)2(2, 2'-bpy)] and the lattice water molecules are interlinked via intermolecular O—H…O and N—H…O hydrogen bonds, generating a 1D chainlike structure, which is linked to adjacent ones through intermolecular π … π interactions forming a 3D supramolecular architecture. The electrochemical and luminescent properties of complexes 1 and 2 have also been investigated.
In the absence/presence of chelating N ancillary ligand, 2, 2'-bipyridine (2, 2'-bpy), treatment of 5-methyl-1H-pyrazole-3-carboxylic acid (H2MPCA) with corresponding Mn(Ⅱ)/Ni(Ⅱ) metal salts afforded two complexes, [Mn(HMPCA)2(H2O)2] (1) and[Ni(HMPCA)2(2, 2'-bpy)]·2H2O (2). In mononuclear complexes 1 and 2, each metal ion locates in a distorted octahedral geometry, and the HMPCA-ligands in 1 and 2 both act as a N, O-chelating ligand. In 1, by the function of intermolecular N—H…O and O—H…O hydrogen bonds, the independent[Mn(HMPCA)2 (H2O)2] units are packed into a porous 3D supramolecular structure with 1D nanotube. In 2, the mononuclear components[Ni(HMPCA)2(2, 2'-bpy)] and the lattice water molecules are interlinked via intermolecular O—H…O and N—H…O hydrogen bonds, generating a 1D chainlike structure, which is linked to adjacent ones through intermolecular π … π interactions forming a 3D supramolecular architecture. The electrochemical and luminescent properties of complexes 1 and 2 have also been investigated.
2021, 37(8): 1457-1464
doi: 10.11862/CJIC.2021.172
Abstract:
A series of PtCo/C catalysts etched with different amounts of nitric acid were synthesized by stepwise synthesis. Tested by fuel cell test device, PtCo/C catalysts showed good performance at the condition of low loading. Under 50 kPa back pressure, the current density at 0.9 V reached 44 mA·cm-2 and the current density at 0.8 V exceeded 300 mA·cm-2. Under 200 kPa back pressure, the highest power density exceeded 1 300 mW·cm-2. The morphology and structure of PtCo/C catalysts were characterized by X-ray diffraction (XRD) and transmission electron microscope (TEM). XRD patterns show that Pt mainly exists in the form of Pt3Co and Pt nanoparticles. The fuel cell test data show that among the series of catalysts, PtCo/C catalysts treated with aqueous solution prepared with 2 mL nitric acid (mass ratio of 65%) has the best fuel cell performance.
A series of PtCo/C catalysts etched with different amounts of nitric acid were synthesized by stepwise synthesis. Tested by fuel cell test device, PtCo/C catalysts showed good performance at the condition of low loading. Under 50 kPa back pressure, the current density at 0.9 V reached 44 mA·cm-2 and the current density at 0.8 V exceeded 300 mA·cm-2. Under 200 kPa back pressure, the highest power density exceeded 1 300 mW·cm-2. The morphology and structure of PtCo/C catalysts were characterized by X-ray diffraction (XRD) and transmission electron microscope (TEM). XRD patterns show that Pt mainly exists in the form of Pt3Co and Pt nanoparticles. The fuel cell test data show that among the series of catalysts, PtCo/C catalysts treated with aqueous solution prepared with 2 mL nitric acid (mass ratio of 65%) has the best fuel cell performance.
2021, 37(8): 1465-1474
doi: 10.11862/CJIC.2021.173
Abstract:
Photocatalytic degradation of organic pollutants in actual wastewater requires exploring the influence of ions on the performance of photocatalysts. In this work, ZrCl4 and 2, 5-dihydroxyterephthalic acid were used as raw materials, and the metal-organic framework material UIO-66-2OH was successfully prepared by the hydrothermal synthesis method. The structure of UIO-66-2OH was characterized by infrared (IR), X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and scanning electron microscope (SEM). The photocatalytic performance of UIO-66-2OH was explored by using common metal cations and inorganic anions in water. The studies have found that metal cations Fe3+ and inorganic anions HCO3- and CO32-can accelerate the rate of photocatalytic degradation. However, the metal ions Na+, K+, Ca2+, Mg2+, Cu2+ and inorganic anions Cl-, SO42-, PO43- can inhibit the photocatalytic performance, and the higher the ion valence, the more obvious the inhibition effect.
Photocatalytic degradation of organic pollutants in actual wastewater requires exploring the influence of ions on the performance of photocatalysts. In this work, ZrCl4 and 2, 5-dihydroxyterephthalic acid were used as raw materials, and the metal-organic framework material UIO-66-2OH was successfully prepared by the hydrothermal synthesis method. The structure of UIO-66-2OH was characterized by infrared (IR), X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and scanning electron microscope (SEM). The photocatalytic performance of UIO-66-2OH was explored by using common metal cations and inorganic anions in water. The studies have found that metal cations Fe3+ and inorganic anions HCO3- and CO32-can accelerate the rate of photocatalytic degradation. However, the metal ions Na+, K+, Ca2+, Mg2+, Cu2+ and inorganic anions Cl-, SO42-, PO43- can inhibit the photocatalytic performance, and the higher the ion valence, the more obvious the inhibition effect.
2021, 37(8): 1475-1481
doi: 10.11862/CJIC.2021.156
Abstract:
Through the one-pot method, for the first time, the NMR imaging reagent Mn2+ and the fluorescence imaging reagent fluorescein (FSD) were self-assembled on a simple metal organic framework (Mn-FSD). Fortunately, the particle size of as-obtained Mn-FSD can be controlled to the micro-nano level for bioimaging. The in vitro and in vivo outcomes confirm that Mn-FSD can show strong green fluorescence in cells and in nude mice. Simultaneously, Mn-FSD exhibited high relaxivity values (r1=4.95 L·mmol-1·s-1).
Through the one-pot method, for the first time, the NMR imaging reagent Mn2+ and the fluorescence imaging reagent fluorescein (FSD) were self-assembled on a simple metal organic framework (Mn-FSD). Fortunately, the particle size of as-obtained Mn-FSD can be controlled to the micro-nano level for bioimaging. The in vitro and in vivo outcomes confirm that Mn-FSD can show strong green fluorescence in cells and in nude mice. Simultaneously, Mn-FSD exhibited high relaxivity values (r1=4.95 L·mmol-1·s-1).
2021, 37(8): 1482-1492
doi: 10.11862/CJIC.2021.163
Abstract:
The influences of alkali-metal cations on growth and pervaporation (PV) performance of mordenite membranes were investigated in detail with multiple characterization techniques. The results show that the morphology and quality of mordenite membrane are greatly influenced by Li+, Na+, K+ and Cs+ as well as the mixed Na+-Li+, Na+-K+ and Na+-Cs+. It is found that alkali-metal cations play a structure-directing role on the nucleation when aluminosilicate is rearranged by facilitating the dissolution of silicon in initial gel, and then play the structure formation effect for constructing mordenite framework. Na+ has a significant acceleration effect on mordenite crystallization while Li+, K+ and Cs+ exhibit a slower crystallization rate in the equal crystallization time. The replacement of a small amount of Na+ with K+ in synthesis gel can improve the hydrophilicity of membrane surface. Especially, the Na+/K+ ratio (nNa+/nK+) of 2 in synthesis gel resulted in the formation of denser and more hydrophilic mordenite membranes with higher PV performances. For separation of a HAc/H2O mixture containing mass fraction of 90% HAc at 90℃, the membrane showed a high permeation flux of 2.67 kg·m-2·h-1 and a high separation factor of about 4 000. Moreover, the mordenite membrane displayed a long-term acid stability in pervaporation of a 90% HAc/H2O mixture at 90℃ for 240 h.
The influences of alkali-metal cations on growth and pervaporation (PV) performance of mordenite membranes were investigated in detail with multiple characterization techniques. The results show that the morphology and quality of mordenite membrane are greatly influenced by Li+, Na+, K+ and Cs+ as well as the mixed Na+-Li+, Na+-K+ and Na+-Cs+. It is found that alkali-metal cations play a structure-directing role on the nucleation when aluminosilicate is rearranged by facilitating the dissolution of silicon in initial gel, and then play the structure formation effect for constructing mordenite framework. Na+ has a significant acceleration effect on mordenite crystallization while Li+, K+ and Cs+ exhibit a slower crystallization rate in the equal crystallization time. The replacement of a small amount of Na+ with K+ in synthesis gel can improve the hydrophilicity of membrane surface. Especially, the Na+/K+ ratio (nNa+/nK+) of 2 in synthesis gel resulted in the formation of denser and more hydrophilic mordenite membranes with higher PV performances. For separation of a HAc/H2O mixture containing mass fraction of 90% HAc at 90℃, the membrane showed a high permeation flux of 2.67 kg·m-2·h-1 and a high separation factor of about 4 000. Moreover, the mordenite membrane displayed a long-term acid stability in pervaporation of a 90% HAc/H2O mixture at 90℃ for 240 h.
2021, 37(8): 1493-1503
doi: 10.11862/CJIC.2021.159
Abstract:
Two dipalladium complexes[(bpy) 2Pd2(NO3)2](NO3)2, [(dmbpy) 2Pd2(NO3)2](NO3) 2 (bpy=2, 2-bipyridine, dmbpy=4, 4'-dimethyl-2, 2-bipyridine) were used as "clips" to coordinate with ditopic pyrazolate ligands (HL1, HL2), leading to the formation of[Pd2L2]2--type dinuclear coordination "clips" with strong intramolecular Pd(Ⅱ) …Pd(Ⅱ) bonding interaction through a spontaneous deprotonation of the pyrazole ligands in aqueous solution. Such well-defined complexes C1~C4 have been characterized by single-crystal X-ray diffraction analysis, elemental analysis, 1H and 13C NMR, electrospray ionization mass spectrometry (ESI-MS) and IR spectroscopy. Furthermore, all these clip-like dipalladium(Ⅱ) complexes exhibited highly catalytic activities towards Suzuki-coupling reaction under mild conditions.
Two dipalladium complexes[(bpy) 2Pd2(NO3)2](NO3)2, [(dmbpy) 2Pd2(NO3)2](NO3) 2 (bpy=2, 2-bipyridine, dmbpy=4, 4'-dimethyl-2, 2-bipyridine) were used as "clips" to coordinate with ditopic pyrazolate ligands (HL1, HL2), leading to the formation of[Pd2L2]2--type dinuclear coordination "clips" with strong intramolecular Pd(Ⅱ) …Pd(Ⅱ) bonding interaction through a spontaneous deprotonation of the pyrazole ligands in aqueous solution. Such well-defined complexes C1~C4 have been characterized by single-crystal X-ray diffraction analysis, elemental analysis, 1H and 13C NMR, electrospray ionization mass spectrometry (ESI-MS) and IR spectroscopy. Furthermore, all these clip-like dipalladium(Ⅱ) complexes exhibited highly catalytic activities towards Suzuki-coupling reaction under mild conditions.
2021, 37(8): 1504-1512
doi: 10.11862/CJIC.2021.175
Abstract:
Two novel Cu(Ⅰ) complexes, [Cu(dppp) (Bphen)]Cl·1.8CH3OH (1) and[Cu2(CN)2(dppp)(dmp)2]·2.5CH3OH(2) (dppp=1, 3-bis(diphenylphosphanyl) propane, Bphen=4, 7-diphenyl-1, 10-diazaphenanthrene, dmp=2, 9-dimethyl-1, 10-phenanthroline), have been synthesized in a mixture of CH3OH and CH2Cl2 and characterized by single-crystal X-ray diffraction, elemental analysis, IR, 1H NMR and 31P NMR spectroscopy, fluorescence spectra and terahertz time-domain spectroscopy (THz-TDS). The single crystal X-ray diffraction shows that complex 1 is a distorted tetrahedral structure with copper as the center, Bphen and dppp as the chelating ligands. Complex 2 is obtained by mixing CuCN, dppp and dmp in a ratio of 2:1:2. The two phosphates of complex 2 form coordination bonds with two Cu(Ⅰ), and each copper coordinates with a cyanogen and a dmp, respectively. The luminescent spectra show that the emission mechanism of complexes 1 and 2 are metal-to-ligand charge transfer (MLCT). The application of THz-TDS also supports to the study of both the complexes.
Two novel Cu(Ⅰ) complexes, [Cu(dppp) (Bphen)]Cl·1.8CH3OH (1) and[Cu2(CN)2(dppp)(dmp)2]·2.5CH3OH(2) (dppp=1, 3-bis(diphenylphosphanyl) propane, Bphen=4, 7-diphenyl-1, 10-diazaphenanthrene, dmp=2, 9-dimethyl-1, 10-phenanthroline), have been synthesized in a mixture of CH3OH and CH2Cl2 and characterized by single-crystal X-ray diffraction, elemental analysis, IR, 1H NMR and 31P NMR spectroscopy, fluorescence spectra and terahertz time-domain spectroscopy (THz-TDS). The single crystal X-ray diffraction shows that complex 1 is a distorted tetrahedral structure with copper as the center, Bphen and dppp as the chelating ligands. Complex 2 is obtained by mixing CuCN, dppp and dmp in a ratio of 2:1:2. The two phosphates of complex 2 form coordination bonds with two Cu(Ⅰ), and each copper coordinates with a cyanogen and a dmp, respectively. The luminescent spectra show that the emission mechanism of complexes 1 and 2 are metal-to-ligand charge transfer (MLCT). The application of THz-TDS also supports to the study of both the complexes.
2021, 37(8): 1513-1518
doi: 10.11862/CJIC.2021.155
Abstract:
A two-dimensional luminescent coordination polymer based on dinuclear {Zn2(COO)4} second buildings units, [Zn2(L)2(DMSO)2(DMF)] (1, H2L=2-(1, 3-dioxo-1H-benzo[de]isoquinolin-2(3H)-yl) terephthalic acid, DMSO=dimethyl sulfoxide, DMF=dimethylformamide), was synthesized by hydrothermal reaction using H2L ligand and Zn2+. Topological analysis shows that the dinuclear {Zn2(COO)4} unit can be regarded as a 4-linked node and forms a (4, 4) net topology with L2- linker. 1 also exhibited a selective luminescence quenching type response to Fe3+ with detection limit as low as 2.8 μmol·L-1. 1 has good anti-interference ability for the detection of Fe3+, and can be regenerated and recycled for several times by washing with DMF solvent.
A two-dimensional luminescent coordination polymer based on dinuclear {Zn2(COO)4} second buildings units, [Zn2(L)2(DMSO)2(DMF)] (1, H2L=2-(1, 3-dioxo-1H-benzo[de]isoquinolin-2(3H)-yl) terephthalic acid, DMSO=dimethyl sulfoxide, DMF=dimethylformamide), was synthesized by hydrothermal reaction using H2L ligand and Zn2+. Topological analysis shows that the dinuclear {Zn2(COO)4} unit can be regarded as a 4-linked node and forms a (4, 4) net topology with L2- linker. 1 also exhibited a selective luminescence quenching type response to Fe3+ with detection limit as low as 2.8 μmol·L-1. 1 has good anti-interference ability for the detection of Fe3+, and can be regenerated and recycled for several times by washing with DMF solvent.
2021, 37(8): 1519-1526
doi: 10.11862/CJIC.2021.174
Abstract:
Altering the synthetic strategies and further tuning the magnetic dynamics of single-ion magnets (SIMs) are critical tasks for chemists. Two mononuclear Dy(Ⅲ) complexes[DyL2(H2O)2]ClO4·2H2O·2CH3CN·CH3OH (1) and [DyL2(H2O)2]CF3SO3·4H2O·2CH3OH (2) have been successfully synthesized by using tris(2-hydroxybenzylidene) triaminoguanidine ligand (L). Structural and magnetic investigations reveal that different counter anions play an important role in dynamic magnetic behaviors of 1 and 2. In both the complexes the Dy(Ⅲ) centers are eight-coordinated with triangular dodecahedron D2d symmetry. They all showed single-ion magnets (SIMs) behavior under zero dc applied field with effective energy barriers (Ueff) of 358 K (1) and 309 K (2), respectively. A comparison of the structural parameters shows that the small but significant changes at axial positions in bond lengths and bond angles affect the axial ligand field which in turn is mainly responsible for distinct magnetic properties of both the complexes.
Altering the synthetic strategies and further tuning the magnetic dynamics of single-ion magnets (SIMs) are critical tasks for chemists. Two mononuclear Dy(Ⅲ) complexes[DyL2(H2O)2]ClO4·2H2O·2CH3CN·CH3OH (1) and [DyL2(H2O)2]CF3SO3·4H2O·2CH3OH (2) have been successfully synthesized by using tris(2-hydroxybenzylidene) triaminoguanidine ligand (L). Structural and magnetic investigations reveal that different counter anions play an important role in dynamic magnetic behaviors of 1 and 2. In both the complexes the Dy(Ⅲ) centers are eight-coordinated with triangular dodecahedron D2d symmetry. They all showed single-ion magnets (SIMs) behavior under zero dc applied field with effective energy barriers (Ueff) of 358 K (1) and 309 K (2), respectively. A comparison of the structural parameters shows that the small but significant changes at axial positions in bond lengths and bond angles affect the axial ligand field which in turn is mainly responsible for distinct magnetic properties of both the complexes.
2021, 37(8): 1375-1380
doi: 10.11862/CJIC.2021.109
Abstract:
Half-sandwich 16e carborane compound Cp*CoS2C2B10H10 reacts with diphenylmethylphosphine, phenyl-dimethylphosphine and trimethylphosphine to afford addition compounds (Cp*CoS2C2B10H10) (PPh2Me) (1), (Cp*CoS2C2B10H10) (PPhMe2) (2) and (Cp*CoS2C2B10H10) (PMe3) (3), respectively. 1, 2 and 3 have been characterized by IR, NMR, elemental analysis, mass spectrum and single-crystal X-ray diffraction analysis. The ultraviolet spectra of compounds 1, 2 and 3 in acetonitrile showed two absorb bands, where the first bands were located at 321, 316 and 321 nm, respectively, and the second bands were located at 425, 399 and 407 nm, respectively. The fluorescence spectrum results of compounds 1, 2 and 3 exhibited maximum emission peaks at about 406 nm.
Half-sandwich 16e carborane compound Cp*CoS2C2B10H10 reacts with diphenylmethylphosphine, phenyl-dimethylphosphine and trimethylphosphine to afford addition compounds (Cp*CoS2C2B10H10) (PPh2Me) (1), (Cp*CoS2C2B10H10) (PPhMe2) (2) and (Cp*CoS2C2B10H10) (PMe3) (3), respectively. 1, 2 and 3 have been characterized by IR, NMR, elemental analysis, mass spectrum and single-crystal X-ray diffraction analysis. The ultraviolet spectra of compounds 1, 2 and 3 in acetonitrile showed two absorb bands, where the first bands were located at 321, 316 and 321 nm, respectively, and the second bands were located at 425, 399 and 407 nm, respectively. The fluorescence spectrum results of compounds 1, 2 and 3 exhibited maximum emission peaks at about 406 nm.
2021, 37(8): 1381-1389
doi: 10.11862/CJIC.2021.177
Abstract:
Taking 3-(4'-carboxyl-phenyloxy) benzoic acid (3, 4'-H2oba) and phenanthroline (phen) as ligands, two coordination polymers (CPs) [M(3, 4'-oba) (phen) (H2O)]n (M=Zn (1), Cu (2)) were synthesized by hydrothermal method and their structures were characterized by X-ray single crystal diffraction. CP 1 features a one-dimensional chain structure. The coordination environment of Zn2+ ion is[ZnO3N2], forming tetragonal vertebral configuration. The Zn2+ ions are linked by 3, 4'-oba ligands through μ1: η1η0/μ1: η1η0 coordination modes. CP 2 has a structure with[CuO4N2] coordination unit. Ligand 3, 4'-oba uses the pattern of μ1: η1η0/μ1: η1η1 to connect two Cu2+ to form a 1D zigzag chain structure. The 1D chain forms a 2D supramolecular network structure through hydrogen bonds (C—H…O in 1 and O—H…O in 2). Ligand phen coordinates with Zn2+/Cu2+ by bidentate chelation mode. CP 1 showed strong fluorescence, which is attributed to the π*-π transition of the ligand. The fluorescence properties of 1 in different solvents and the fluorescence sensitization effect on lanthanide metal ion were studied. The fluorescence of CP 1 was quenched by acetone molecule, and it can sensitize the rare earth metal Tb3+ ions to emit strong green fluorescence. Therefore, 1 can be used as a fluorescence sensor for detecting acetone molecule and Tb3+ ion.
Taking 3-(4'-carboxyl-phenyloxy) benzoic acid (3, 4'-H2oba) and phenanthroline (phen) as ligands, two coordination polymers (CPs) [M(3, 4'-oba) (phen) (H2O)]n (M=Zn (1), Cu (2)) were synthesized by hydrothermal method and their structures were characterized by X-ray single crystal diffraction. CP 1 features a one-dimensional chain structure. The coordination environment of Zn2+ ion is[ZnO3N2], forming tetragonal vertebral configuration. The Zn2+ ions are linked by 3, 4'-oba ligands through μ1: η1η0/μ1: η1η0 coordination modes. CP 2 has a structure with[CuO4N2] coordination unit. Ligand 3, 4'-oba uses the pattern of μ1: η1η0/μ1: η1η1 to connect two Cu2+ to form a 1D zigzag chain structure. The 1D chain forms a 2D supramolecular network structure through hydrogen bonds (C—H…O in 1 and O—H…O in 2). Ligand phen coordinates with Zn2+/Cu2+ by bidentate chelation mode. CP 1 showed strong fluorescence, which is attributed to the π*-π transition of the ligand. The fluorescence properties of 1 in different solvents and the fluorescence sensitization effect on lanthanide metal ion were studied. The fluorescence of CP 1 was quenched by acetone molecule, and it can sensitize the rare earth metal Tb3+ ions to emit strong green fluorescence. Therefore, 1 can be used as a fluorescence sensor for detecting acetone molecule and Tb3+ ion.
2021, 37(8): 1390-1398
doi: 10.11862/CJIC.2021.148
Abstract:
CuFe@MOFs derived catalysts were synthesized by introducing a second ligand, p-aminobenzoic acid, in the hydrothermal synthesis of MIL-88B(Fe), which was followed by impregnation with Cu species. The physicochemical properties of the catalysts were characterized by X-ray diffraction (XRD), H2-temperature programmed reduction (H2-TPR), N2 adsorption-desorption, scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The catalytic performance of the catalysts for hydrogenation of CO2 to C2+ alcohol (C2+OH) was tested in a fixed bed reactor. The results show that the elements of active components were evenly dispersed, and the active species distribution on the catalyst surface can be controlled by adjusting the molar ratio of two ligands (terephthalic acid to p-aminobenzoic acid ligands) in the raw materials. When the molar ratio of terephthalic acid to p-aminobenzoic acid was 5:2, the proportion of low-valence iron of the as-obtained catalyst was the highest (71.27%). Accordingly, this catalyst showed the best performance for CO2 hydrogenation to C2+OH, that the conversion of CO2 was 8.80%, the selectivity of total alcohol (ROH) was 31.52% and the molar fraction of C2+OH was 94.70%. This might be due to the high proportion of low-valence iron species and the well-dispersed active components.
CuFe@MOFs derived catalysts were synthesized by introducing a second ligand, p-aminobenzoic acid, in the hydrothermal synthesis of MIL-88B(Fe), which was followed by impregnation with Cu species. The physicochemical properties of the catalysts were characterized by X-ray diffraction (XRD), H2-temperature programmed reduction (H2-TPR), N2 adsorption-desorption, scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The catalytic performance of the catalysts for hydrogenation of CO2 to C2+ alcohol (C2+OH) was tested in a fixed bed reactor. The results show that the elements of active components were evenly dispersed, and the active species distribution on the catalyst surface can be controlled by adjusting the molar ratio of two ligands (terephthalic acid to p-aminobenzoic acid ligands) in the raw materials. When the molar ratio of terephthalic acid to p-aminobenzoic acid was 5:2, the proportion of low-valence iron of the as-obtained catalyst was the highest (71.27%). Accordingly, this catalyst showed the best performance for CO2 hydrogenation to C2+OH, that the conversion of CO2 was 8.80%, the selectivity of total alcohol (ROH) was 31.52% and the molar fraction of C2+OH was 94.70%. This might be due to the high proportion of low-valence iron species and the well-dispersed active components.
2021, 37(8): 1399-1406
doi: 10.11862/CJIC.2021.144
Abstract:
LiFePO4 cathode materials with different doping amounts of Mn were synthesized by solvothermal using water and ethylene glycol as solvent. The crystal phase, morphology and electrochemical performance were studied. The results show that Mn has a positive effect in LiFePO4 cathode material, and the Mn-doping can improve the electrochemical performance of LiFePO4. On the one hand, a small amount of Mn-doping can broaden the lithium ion diffusion channel and reduce the charge transfer resistance. On the other hand, when the doped amount of Mn was too much, its own poor kinetic properties will cause the charge transfer to be blocked, resulting in battery polarization and serious capacity attenuation.
LiFePO4 cathode materials with different doping amounts of Mn were synthesized by solvothermal using water and ethylene glycol as solvent. The crystal phase, morphology and electrochemical performance were studied. The results show that Mn has a positive effect in LiFePO4 cathode material, and the Mn-doping can improve the electrochemical performance of LiFePO4. On the one hand, a small amount of Mn-doping can broaden the lithium ion diffusion channel and reduce the charge transfer resistance. On the other hand, when the doped amount of Mn was too much, its own poor kinetic properties will cause the charge transfer to be blocked, resulting in battery polarization and serious capacity attenuation.
2021, 37(8): 1407-1413
doi: 10.11862/CJIC.2021.166
Abstract:
Herein, we prepared N-doped porous carbon (NPC) loaded with isolated single Fe atom (Fe-ISAs/NPC) electrocatalyst with high catalytic activity as counter electrode for dye-sensitized solar cells (DSSCs) through molecular cage-encapsulated-precursor pyrolysis. Effect of film thickness of Fe-ISAs/NPC counter electrode on the performance of DSSCs was studied by electrochemical measurement. The results showed that the highest photoelectric conversion efficiency of DSSCs was 8.03% when the film thickness of Fe-ISAs/NPC counter electrode was 16 μm.
Herein, we prepared N-doped porous carbon (NPC) loaded with isolated single Fe atom (Fe-ISAs/NPC) electrocatalyst with high catalytic activity as counter electrode for dye-sensitized solar cells (DSSCs) through molecular cage-encapsulated-precursor pyrolysis. Effect of film thickness of Fe-ISAs/NPC counter electrode on the performance of DSSCs was studied by electrochemical measurement. The results showed that the highest photoelectric conversion efficiency of DSSCs was 8.03% when the film thickness of Fe-ISAs/NPC counter electrode was 16 μm.
2021, 37(8): 1414-1420
doi: 10.11862/CJIC.2021.182
Abstract:
The low defect formation energy and surface dangling bonds of organic-inorganic hybrid perovskite can cause the formation of Pb defects in the film. Pb defects belong to the deep level defects, which can reduce the device performances by acting as the charge trap sites to accelerate the non-radiative recombination of carriers, and resulting in poor interface contact and carrier transmission performance. Therefore, passivating the Pb defects in perovskite film is necessary. In this study, dithizone was used as the secondary crystallization inducer and Pb defect passivator of the organic-inorganic hybrid perovskite film. After post-treating the perovskite film with dithizone, the size of the perovskite grains and the film morphology were regulated. Further research results show that dithizone can passivate the Pb defects effectively by coordinating with lead ions, induce secondary crystallization of perovskite crystals, improve the quality of the film, and thus enhancing the device efficiency and stability.
The low defect formation energy and surface dangling bonds of organic-inorganic hybrid perovskite can cause the formation of Pb defects in the film. Pb defects belong to the deep level defects, which can reduce the device performances by acting as the charge trap sites to accelerate the non-radiative recombination of carriers, and resulting in poor interface contact and carrier transmission performance. Therefore, passivating the Pb defects in perovskite film is necessary. In this study, dithizone was used as the secondary crystallization inducer and Pb defect passivator of the organic-inorganic hybrid perovskite film. After post-treating the perovskite film with dithizone, the size of the perovskite grains and the film morphology were regulated. Further research results show that dithizone can passivate the Pb defects effectively by coordinating with lead ions, induce secondary crystallization of perovskite crystals, improve the quality of the film, and thus enhancing the device efficiency and stability.
2021, 37(8): 1421-1429
doi: 10.11862/CJIC.2021.162
Abstract:
A two-step hydrothermal method was used to prepare nickel foam (NF) supported Fe2O3 nanoparticles@Ni3S2 nanowires 3D network electrode (Fe2O3@Ni3S2/NF). The crystal phase and microstructure features of the products were characterized in detail by using some characterization techniques including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and N2 adsorption-desorption measurement and so on. The in situ surface chemical etching process under hydrothermal conditions leads to the generation of Ni3S2 nanowires 3D network that binds to NF firmly with relatively low interfacial resistances. In an aqueous electrolyte of 1 mol·L-1 KOH, the electrocatalytic oxygen evolution reaction (OER) performance of the obtained electrodes was tested by linear sweep voltammetry (LSV), chronopotentiometry, and electrochemical impedance test (EIS). At a ultrathigh current density of 100 mA·cm-2, Fe2O3@Ni3S2/NF electrode showed a low OER overpotential of only 223 mV, which was 285 mV lower than that of Ni3S2/NF electrode (before growth of Fe2O3). These excellent properties are attributed to the faster reaction kinetics and smaller charge transfer impedance of Fe2O3@Ni3S2/NF electrode comparing with Ni3S2/NF.
A two-step hydrothermal method was used to prepare nickel foam (NF) supported Fe2O3 nanoparticles@Ni3S2 nanowires 3D network electrode (Fe2O3@Ni3S2/NF). The crystal phase and microstructure features of the products were characterized in detail by using some characterization techniques including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and N2 adsorption-desorption measurement and so on. The in situ surface chemical etching process under hydrothermal conditions leads to the generation of Ni3S2 nanowires 3D network that binds to NF firmly with relatively low interfacial resistances. In an aqueous electrolyte of 1 mol·L-1 KOH, the electrocatalytic oxygen evolution reaction (OER) performance of the obtained electrodes was tested by linear sweep voltammetry (LSV), chronopotentiometry, and electrochemical impedance test (EIS). At a ultrathigh current density of 100 mA·cm-2, Fe2O3@Ni3S2/NF electrode showed a low OER overpotential of only 223 mV, which was 285 mV lower than that of Ni3S2/NF electrode (before growth of Fe2O3). These excellent properties are attributed to the faster reaction kinetics and smaller charge transfer impedance of Fe2O3@Ni3S2/NF electrode comparing with Ni3S2/NF.
2021, 37(8): 1430-1438
doi: 10.11862/CJIC.2021.167
Abstract:
The quasi-spherical α-calcium sulfate hemihydrate (α-CSH) with the size of 6~10 μm has been synthesized from flue gas desulphurization (FGD) gypsum by two-step hydrothermal method under the regulation of N, N'-methylenediacrylamide (MBA). The effect of MBA addition on the morphology and size of α-CSH product and the regulation mechanism was investigated by FTIR and EDS measurements as well as ethylene glycol concentration-dependent experiments. MBA could be preferentially absorbed on the (111) plane of α-CSH to inhibit the growth of α-CSH along c axis, and form a three-dimensional gel network to exert the confinement effect on the nucleation and growth of α-CSH particles. In addition, after undergoing physical washing and two-step chemical hydrothermal treatment, the whiteness of the synthesized α-CSH was improved from 39.22% to 92.06%.
The quasi-spherical α-calcium sulfate hemihydrate (α-CSH) with the size of 6~10 μm has been synthesized from flue gas desulphurization (FGD) gypsum by two-step hydrothermal method under the regulation of N, N'-methylenediacrylamide (MBA). The effect of MBA addition on the morphology and size of α-CSH product and the regulation mechanism was investigated by FTIR and EDS measurements as well as ethylene glycol concentration-dependent experiments. MBA could be preferentially absorbed on the (111) plane of α-CSH to inhibit the growth of α-CSH along c axis, and form a three-dimensional gel network to exert the confinement effect on the nucleation and growth of α-CSH particles. In addition, after undergoing physical washing and two-step chemical hydrothermal treatment, the whiteness of the synthesized α-CSH was improved from 39.22% to 92.06%.
2021, 37(8): 1527-1528
doi: 10.11862/CJIC.2021.169
Abstract:
