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2018 Volume 34 Issue 8
2018, 34(8): 1399-1412
doi: 10.11862/CJIC.2018.195
Abstract:
pH-responsive drug nanocarriers are a kind of important multifunctional nanocarriers due to their intelligent properties of acid sensitive or alkali sensitive release, and have received extensive attention from researchers. Especially, acid sensitive nanocarriers can be applied for controlled release at weak acid microenvironment of tumor, wich play an active role at some biomedicine application such as targeted delivery of drugs and targeted therapy for cancer. In this paper, the typical fabrication methods for pH-responsive drug nanocarriers in recent years have been summarized, and the pH-responsive drug release mechanisms triggered by three ways have been systematically introduced. Firstly, pH-responsive mechanism triggered by covalent bond, in which imine bond, acetal bond, ester bond, coordination bond and others covalent bond can be used individually as pH initiator. Secondly, pH-responsive mechanisms triggered by intermolecular forces, in which both electrostatic interaction and hydrogen bond are applied for pH-responsive release drug. Thirdly, pH-responsive mechanism triggered by physical structure of nanocarries, in which both polymer swelling at diffirent pH values and calcium phosphate dissolving in the acid environment can result in controlled drug release. The loading properties, release properties in vitro, cytotoxicity in vitro, anticancer properties in vivo and distribution properties in vivo of pH-responsive drug nanocarriers are also expounded. Various experimental parameters of pH-responsive drug nanocarriers have been enumerated in detail, which provide the performance and methodological references for the in-depth studies of pH-responsive nanocarries.
pH-responsive drug nanocarriers are a kind of important multifunctional nanocarriers due to their intelligent properties of acid sensitive or alkali sensitive release, and have received extensive attention from researchers. Especially, acid sensitive nanocarriers can be applied for controlled release at weak acid microenvironment of tumor, wich play an active role at some biomedicine application such as targeted delivery of drugs and targeted therapy for cancer. In this paper, the typical fabrication methods for pH-responsive drug nanocarriers in recent years have been summarized, and the pH-responsive drug release mechanisms triggered by three ways have been systematically introduced. Firstly, pH-responsive mechanism triggered by covalent bond, in which imine bond, acetal bond, ester bond, coordination bond and others covalent bond can be used individually as pH initiator. Secondly, pH-responsive mechanisms triggered by intermolecular forces, in which both electrostatic interaction and hydrogen bond are applied for pH-responsive release drug. Thirdly, pH-responsive mechanism triggered by physical structure of nanocarries, in which both polymer swelling at diffirent pH values and calcium phosphate dissolving in the acid environment can result in controlled drug release. The loading properties, release properties in vitro, cytotoxicity in vitro, anticancer properties in vivo and distribution properties in vivo of pH-responsive drug nanocarriers are also expounded. Various experimental parameters of pH-responsive drug nanocarriers have been enumerated in detail, which provide the performance and methodological references for the in-depth studies of pH-responsive nanocarries.
2018, 34(8): 1413-1420
doi: 10.11862/CJIC.2018.187
Abstract:
The variable C-C bond of o-carborane cage was treated as a vibrational factor. A temptation to synthesize AIE-active o-carborane luminophores were carried out via coupling o-carborane with conventional luminophores who suffered from ACQ (aggregation-caused quenching) effect. Meanwhile, the photophysical properties were investigated by UV-Vis spectra, DFT calculations, PL spectra and crystal structure analysis. The results indicate that different substituents (H, ethyl and phenyl) in o-carboranes could remarkably affect its vibration performance. Ultimately, photophysical properties can be tuned from ACQ to AIE.
The variable C-C bond of o-carborane cage was treated as a vibrational factor. A temptation to synthesize AIE-active o-carborane luminophores were carried out via coupling o-carborane with conventional luminophores who suffered from ACQ (aggregation-caused quenching) effect. Meanwhile, the photophysical properties were investigated by UV-Vis spectra, DFT calculations, PL spectra and crystal structure analysis. The results indicate that different substituents (H, ethyl and phenyl) in o-carboranes could remarkably affect its vibration performance. Ultimately, photophysical properties can be tuned from ACQ to AIE.
2018, 34(8): 1547-1554
doi: 10.11862/CJIC.2018.170
Abstract:
Two new lanthanide complexes based on Schiff base ligand, namely[Dy(salen)2]3·3C2H9N2·2CH3OH (1) and[Ho(salen)2]3·3C2H9N2·1.5CH3OH (2), (H2salen=N, N'-bis(3-methoxysalicylidene)ethylene-1, 2-diamine), have been synthesized and characterized. Single-crystal X-ray diffractions reveal that 1 and 2 crystallize in the same monoclinic space group C2, and have similar coordination environment around the metallic centers. Single molecule magnets (SMMs) behaviors have been observed in 1 and 2 with/without an applied magnetic field.
Two new lanthanide complexes based on Schiff base ligand, namely[Dy(salen)2]3·3C2H9N2·2CH3OH (1) and[Ho(salen)2]3·3C2H9N2·1.5CH3OH (2), (H2salen=N, N'-bis(3-methoxysalicylidene)ethylene-1, 2-diamine), have been synthesized and characterized. Single-crystal X-ray diffractions reveal that 1 and 2 crystallize in the same monoclinic space group C2, and have similar coordination environment around the metallic centers. Single molecule magnets (SMMs) behaviors have been observed in 1 and 2 with/without an applied magnetic field.
2018, 34(8): 1555-1565
doi: 10.11862/CJIC.2018.175
Abstract:
Effects of high-energy ball milling on the microstructures of Si powders and consequently on the efficiency of Si-water reaction and the hydrogen generation behaviors are studied. During the milling process, both particle sizes and crystallite sizes of the powders decrease, but agglomerations, as well as the content of oxygen, internal strains, distortions and dislocations in the powders increase, and amorphous phase transformation of Si also appears on the particle surface. The increasing defects, including grain boundaries, internal strains, distortions and dislocations, amorphous phase transformation and powder refinement contribute to the hydrolysis performance of the powders. However, the growing contamination and agglomerations deteriorate the hydrolysis performance of the Si powders. The Si powders milled for 1 h have the best hydrolysis performances and produce 1 484.2 mL·g-1Si at 70℃, whose hydrogen conversion rate reaches 94%. However, the residual~6%(w/w) of Si is out of reaction primarily owing to the fact that the hydrolysis byproduct SiO2 adhering on the Si surface restrains the further reaction.
Effects of high-energy ball milling on the microstructures of Si powders and consequently on the efficiency of Si-water reaction and the hydrogen generation behaviors are studied. During the milling process, both particle sizes and crystallite sizes of the powders decrease, but agglomerations, as well as the content of oxygen, internal strains, distortions and dislocations in the powders increase, and amorphous phase transformation of Si also appears on the particle surface. The increasing defects, including grain boundaries, internal strains, distortions and dislocations, amorphous phase transformation and powder refinement contribute to the hydrolysis performance of the powders. However, the growing contamination and agglomerations deteriorate the hydrolysis performance of the Si powders. The Si powders milled for 1 h have the best hydrolysis performances and produce 1 484.2 mL·g-1Si at 70℃, whose hydrogen conversion rate reaches 94%. However, the residual~6%(w/w) of Si is out of reaction primarily owing to the fact that the hydrolysis byproduct SiO2 adhering on the Si surface restrains the further reaction.
2018, 34(8): 1566-1572
doi: 10.11862/CJIC.2018.191
Abstract:
Reactions of Cu(Ⅱ) or Cd(Ⅱ) salts, 4-(imidazol-1-yl)-benzoic acid (HIBA) with or without 5-nitroiso-phthalic acid (H2NPA) as co-ligand result in three coordination polymers (CPs), namely, {[Cu(IBA)2]·DMF}n (1), {[Cd(IBA)2(H2O)]·3H2O}n (2), and[Cd3(IBA)2(NPA)2]n (3). Compounds 1 and 2 exhibit 3D 4-and 3-fold interpene-trating diamondoid frameworks, respectively. Compound 3 displays a 3D mixed-ligand framework with 1D Cd-carboxylate secondary building blocks bridged by IBA- and NPA2- ligands. The phase purity and luminescent properties of selected compounds have also been explored.
Reactions of Cu(Ⅱ) or Cd(Ⅱ) salts, 4-(imidazol-1-yl)-benzoic acid (HIBA) with or without 5-nitroiso-phthalic acid (H2NPA) as co-ligand result in three coordination polymers (CPs), namely, {[Cu(IBA)2]·DMF}n (1), {[Cd(IBA)2(H2O)]·3H2O}n (2), and[Cd3(IBA)2(NPA)2]n (3). Compounds 1 and 2 exhibit 3D 4-and 3-fold interpene-trating diamondoid frameworks, respectively. Compound 3 displays a 3D mixed-ligand framework with 1D Cd-carboxylate secondary building blocks bridged by IBA- and NPA2- ligands. The phase purity and luminescent properties of selected compounds have also been explored.
2018, 34(8): 1573-1580
doi: 10.11862/CJIC.2018.183
Abstract:
Reaction of tungsten or molybdenum carbonyl with 3(5)-hydroxymethyl-5(3)-methylpyrazole (L1), 4-hydroxymethylpyrazole (L2) and bis(3-hydroxymethyl-5-methylpyrazol-1-yl)methane (L3) yielded complexes LW(CO)5 (L=L1 or L2) and L3M(CO)4 (M=Mo or W), respectively. These complexes have been fully characterized by NMR, IR and X-ray crystal structural analyses, indicating that they form 1D or 2D organometallic supramolecular architectures through O-H…O, N-H…O and O-H…OC-M hydrogen bonding interactions, and these structures are significantly affected by the relative position of the hydroxymethyl group on the pyrazole ring. In addition, these complexes show moderate catalytic activity for the cyclotrimerization reaction of phenylacetylene.
Reaction of tungsten or molybdenum carbonyl with 3(5)-hydroxymethyl-5(3)-methylpyrazole (L1), 4-hydroxymethylpyrazole (L2) and bis(3-hydroxymethyl-5-methylpyrazol-1-yl)methane (L3) yielded complexes LW(CO)5 (L=L1 or L2) and L3M(CO)4 (M=Mo or W), respectively. These complexes have been fully characterized by NMR, IR and X-ray crystal structural analyses, indicating that they form 1D or 2D organometallic supramolecular architectures through O-H…O, N-H…O and O-H…OC-M hydrogen bonding interactions, and these structures are significantly affected by the relative position of the hydroxymethyl group on the pyrazole ring. In addition, these complexes show moderate catalytic activity for the cyclotrimerization reaction of phenylacetylene.
2018, 34(8): 1581-1589
doi: 10.11862/CJIC.2018.192
Abstract:
Cabon coated LiFe0.5Co0.5PO4 solid solution (LiFe0.5Co0.5PO4/C, LFCP/C) were synthesized via a facile rheological phase method using iron phosphate tetrahydrate (FePO4·4H2O) and iron oxalate dihydrate (FeC2O4·2H2O) as iron source, respectively. The phase composition, particle morphology and electrochemical performance for the as-prepared materials were characterized by methods including X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and galvanostatic charge-discharge measurements. Results demonstrate that both LFCP/C samples possess olivine structure with high crystallinity, while there are significant difference in particle size distribution, carbon coating effect and electrochemical properties. As cathode for lithium ion batteries (LIBs), the LFCP/C obtained by FeC2O4·2H2O as reactant exhibits better electrochemical performance than that by FePO4·4H2O, delivering a specific discharge capacity of 137.5 mAh·g-1 at 0.1C (1C=150 mA·g-1) rate in the voltage range of 2.5~5.0 V, and even at 10C rate, a specific capacity of 57.6 mAh·g-1 is still maintained. Meanwhile, it shows excellent cyclability with a capacity retention rate of 78.1% after 100 cycles at 0.5C. The better electrochemical performance of LFCP/C obtained by FeC2O4·2H2O can be mainly ascribed to its smaller average particle size, higher BET specific surface area, and more appealing carbon coating effect.
Cabon coated LiFe0.5Co0.5PO4 solid solution (LiFe0.5Co0.5PO4/C, LFCP/C) were synthesized via a facile rheological phase method using iron phosphate tetrahydrate (FePO4·4H2O) and iron oxalate dihydrate (FeC2O4·2H2O) as iron source, respectively. The phase composition, particle morphology and electrochemical performance for the as-prepared materials were characterized by methods including X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and galvanostatic charge-discharge measurements. Results demonstrate that both LFCP/C samples possess olivine structure with high crystallinity, while there are significant difference in particle size distribution, carbon coating effect and electrochemical properties. As cathode for lithium ion batteries (LIBs), the LFCP/C obtained by FeC2O4·2H2O as reactant exhibits better electrochemical performance than that by FePO4·4H2O, delivering a specific discharge capacity of 137.5 mAh·g-1 at 0.1C (1C=150 mA·g-1) rate in the voltage range of 2.5~5.0 V, and even at 10C rate, a specific capacity of 57.6 mAh·g-1 is still maintained. Meanwhile, it shows excellent cyclability with a capacity retention rate of 78.1% after 100 cycles at 0.5C. The better electrochemical performance of LFCP/C obtained by FeC2O4·2H2O can be mainly ascribed to its smaller average particle size, higher BET specific surface area, and more appealing carbon coating effect.
2018, 34(8): 1421-1429
doi: 10.11862/CJIC.2018.197
Abstract:
Hierarchical CdS QDs/BiOCl microsphere was prepared via a facile liquid deposition process. XRD, SEM, TEM, HRTEM, XPS, EDS, UV-Vis DRS, PL were used to characterize the phase composition, morphology, composition, light absorption and photoelectric property. Rhodamine (RhB) and phenol were used as the model pollutant to evaluate the photocatalytic performance of CdS QDs/BiOCl under visible and UV light, respectively. The tests indicate that the BiOCl microsphere with size of 5.5 μm is composed of massive nanosheets. Besides, CdS QDs with size of 10~20 nm distributed uniformly on the surface of BiOCl nanosheets. Compared to pure BiOCl and CdS QDs/BiOCl, CdS QDs/BiOCl-3% exhibits the best photocatalytic activity, which is over 2.6 and 5.3 times as high as pure BiOCl for RhB and phenol photodegradation rate. The enhanced photocatalytic performance of the CdS QDs/BiOCl composites should be ascribed to the hierarchical structure of BiOCl which prevented the nanosheets from piling up, enabling CdS QDs to disperse uniformly on the surface of BiOCl nanosheets, moreover, the improved visible light absorption and the high migration efficiency of the photogenerated electron-holes due to the matched band gap and the widespread heterostructure between CdS QDs and BiOCl.
Hierarchical CdS QDs/BiOCl microsphere was prepared via a facile liquid deposition process. XRD, SEM, TEM, HRTEM, XPS, EDS, UV-Vis DRS, PL were used to characterize the phase composition, morphology, composition, light absorption and photoelectric property. Rhodamine (RhB) and phenol were used as the model pollutant to evaluate the photocatalytic performance of CdS QDs/BiOCl under visible and UV light, respectively. The tests indicate that the BiOCl microsphere with size of 5.5 μm is composed of massive nanosheets. Besides, CdS QDs with size of 10~20 nm distributed uniformly on the surface of BiOCl nanosheets. Compared to pure BiOCl and CdS QDs/BiOCl, CdS QDs/BiOCl-3% exhibits the best photocatalytic activity, which is over 2.6 and 5.3 times as high as pure BiOCl for RhB and phenol photodegradation rate. The enhanced photocatalytic performance of the CdS QDs/BiOCl composites should be ascribed to the hierarchical structure of BiOCl which prevented the nanosheets from piling up, enabling CdS QDs to disperse uniformly on the surface of BiOCl nanosheets, moreover, the improved visible light absorption and the high migration efficiency of the photogenerated electron-holes due to the matched band gap and the widespread heterostructure between CdS QDs and BiOCl.
2018, 34(8): 1430-1436
doi: 10.11862/CJIC.2018.159
Abstract:
The porous activated carbon fibers (ACFs) were obtained by the anisotropic mesophase pitch carbon fibers carbonized at 450℃ through a simple KOH chemical activation method. In order to improve the degree of crystallinity of the ACFs, the as-prepared ACFs were modified by carbonization. The effects of carbonization temperatures on the morphology, crystallinity, pore structure and supercapacitive performances of ACFs were systematically investigated. The ACFs carbonized at 1 200℃ (ACFs-1200) electrodes exhibit excellent electrochemical performance with a specific capacity of 204 F·g-1 at 0.1 A·g-1, which show a capacity retention of 97.0% after 1 000 cycles. Even at 20 A·g-1, the electrodes maintain a high specific capacity of 149 F·g-1. The results show that the ACFs-1200 electrodes deliver ultrahigh conductivity, high rate capacity and exceptional cycle stability compared with the non-carbonized ACFs electrodes.
The porous activated carbon fibers (ACFs) were obtained by the anisotropic mesophase pitch carbon fibers carbonized at 450℃ through a simple KOH chemical activation method. In order to improve the degree of crystallinity of the ACFs, the as-prepared ACFs were modified by carbonization. The effects of carbonization temperatures on the morphology, crystallinity, pore structure and supercapacitive performances of ACFs were systematically investigated. The ACFs carbonized at 1 200℃ (ACFs-1200) electrodes exhibit excellent electrochemical performance with a specific capacity of 204 F·g-1 at 0.1 A·g-1, which show a capacity retention of 97.0% after 1 000 cycles. Even at 20 A·g-1, the electrodes maintain a high specific capacity of 149 F·g-1. The results show that the ACFs-1200 electrodes deliver ultrahigh conductivity, high rate capacity and exceptional cycle stability compared with the non-carbonized ACFs electrodes.
2018, 34(8): 1437-1447
doi: 10.11862/CJIC.2018.162
Abstract:
The layered tungsten carbide/carbon composite (WC/C) was synthesized by a programmed temperature method using tungsten sulfide (WS2) as a precursor, sodium chloride (NaCl) as a medium and CO as a gas carbon source. The chemical composition, morphology and structure of the samples were characterized by XRD, XANES and SEM respectively. A thin layered WC with holes has been synthesized because of the natural lamellar structure of WS2 and the anchoring effect of molten NaCl during high-temperature carburization. In addition, NaCl and the metal surface of WS2 could be used as the catalyst for in situ growing of carbon film on the surface of WC effectively, which provides a useful channel for electronic transmission. The electrocatalytic performance of the Pt/WC/C electrocatalyst was investigated after loading a small amount of Pt on WC/C. The results show that the Pt/WC/C electrocatalyst exhibits a better electrocatalytic activity and stability, also a higher resistance toward CO poisoning in methanol oxidation (MOR).
The layered tungsten carbide/carbon composite (WC/C) was synthesized by a programmed temperature method using tungsten sulfide (WS2) as a precursor, sodium chloride (NaCl) as a medium and CO as a gas carbon source. The chemical composition, morphology and structure of the samples were characterized by XRD, XANES and SEM respectively. A thin layered WC with holes has been synthesized because of the natural lamellar structure of WS2 and the anchoring effect of molten NaCl during high-temperature carburization. In addition, NaCl and the metal surface of WS2 could be used as the catalyst for in situ growing of carbon film on the surface of WC effectively, which provides a useful channel for electronic transmission. The electrocatalytic performance of the Pt/WC/C electrocatalyst was investigated after loading a small amount of Pt on WC/C. The results show that the Pt/WC/C electrocatalyst exhibits a better electrocatalytic activity and stability, also a higher resistance toward CO poisoning in methanol oxidation (MOR).
2018, 34(8): 1448-1454
doi: 10.11862/CJIC.2018.179
Abstract:
Two novel heterotrimetallic 1D zigzag chain coordination polymers, {[Cu(Me2valpn)Dy(DMF)2(H2O)Fe(CN)6]·1.5H2O·0.5CH3OH}n (1) and {[Cu(Me2valpn) Tb(DMF)2(H2O)Fe(CN)6]·H2O·CH3OH}n (2) (H2Me2valpn=N, N'-bis(3-methoxysalicylidene)-2, 2-dimethyl-1, 3-diaminopropane), were prepared by stepwise synthetic approach. Single -crystal X-ray diffraction analysis revealed that each[Fe(CN)6]3- is connected with two[Cu(Me2valpn)]Ln(DMF)2(H2O)]3+ fragments in a cis-mode. Accordingly, there are two types of bent bridging linkages (Fe-C≡N-Cu and Fe-C≡N-Ln) in the chain besides the diphenoxo bridges between Cu(Ⅱ) and Ln(Ⅲ). In the temperature range of 9.5~300 K, the dc magnetic susceptibilities of complex 1 are consistent with the Curie-Weiss law and give positive Curie-Weiss constants (θ=13.17 K), indicating the presence of predominant ferromagnetic interactions. The AC magnetic measurements reveal that complex 1 shows no slow magnetization relaxation.
Two novel heterotrimetallic 1D zigzag chain coordination polymers, {[Cu(Me2valpn)Dy(DMF)2(H2O)Fe(CN)6]·1.5H2O·0.5CH3OH}n (1) and {[Cu(Me2valpn) Tb(DMF)2(H2O)Fe(CN)6]·H2O·CH3OH}n (2) (H2Me2valpn=N, N'-bis(3-methoxysalicylidene)-2, 2-dimethyl-1, 3-diaminopropane), were prepared by stepwise synthetic approach. Single -crystal X-ray diffraction analysis revealed that each[Fe(CN)6]3- is connected with two[Cu(Me2valpn)]Ln(DMF)2(H2O)]3+ fragments in a cis-mode. Accordingly, there are two types of bent bridging linkages (Fe-C≡N-Cu and Fe-C≡N-Ln) in the chain besides the diphenoxo bridges between Cu(Ⅱ) and Ln(Ⅲ). In the temperature range of 9.5~300 K, the dc magnetic susceptibilities of complex 1 are consistent with the Curie-Weiss law and give positive Curie-Weiss constants (θ=13.17 K), indicating the presence of predominant ferromagnetic interactions. The AC magnetic measurements reveal that complex 1 shows no slow magnetization relaxation.
2018, 34(8): 1455-1462
doi: 10.11862/CJIC.2018.181
Abstract:
Magnetic phosphorus adsorbent coal-fly-ash magnetic sphere@La2O3 (CMS@La2O3) was synthesized by a chemical precipitation method, using CMS as magnetic core. Structural and magnetic characterization shows that Lanthanum oxide is uniformly coated on the surface of CMSs. The magnetism of the prepared CMS@La2O3 is measured as 20.35 emu·g-1, which is strong enough for effective magnetic separation. The P adsorption performance of the CMS@La2O3 was investigated by the ammonium molybdate spectrophotometric method. It is found that the P adsorption of CMS@La2O3 is closely related to the adsorption time, pH value, and coexisting anions in the wastewater. The highest P adsorption was measured as 19.50 mg·g-1. CO32- and SO42- in the waste water could sharply reduce the P adsorption even in a very low concentration by occupying the P-adsorption site on the La2O3 surface, while the existing of Cl- ions has very little effect on the P adsorption. The P adsorption of CMS@La2O3 is well accordant with the pseudo-second order kinetics equation, indicating that it is dominated by the chemical adsorption. The adsorption reaction could be explained by the "surface hydroxylation-ion exchange" model on the La2O3 surface. The used CMS@La2O3 adsorbent could be recycled for several times after appropriate treatment.
Magnetic phosphorus adsorbent coal-fly-ash magnetic sphere@La2O3 (CMS@La2O3) was synthesized by a chemical precipitation method, using CMS as magnetic core. Structural and magnetic characterization shows that Lanthanum oxide is uniformly coated on the surface of CMSs. The magnetism of the prepared CMS@La2O3 is measured as 20.35 emu·g-1, which is strong enough for effective magnetic separation. The P adsorption performance of the CMS@La2O3 was investigated by the ammonium molybdate spectrophotometric method. It is found that the P adsorption of CMS@La2O3 is closely related to the adsorption time, pH value, and coexisting anions in the wastewater. The highest P adsorption was measured as 19.50 mg·g-1. CO32- and SO42- in the waste water could sharply reduce the P adsorption even in a very low concentration by occupying the P-adsorption site on the La2O3 surface, while the existing of Cl- ions has very little effect on the P adsorption. The P adsorption of CMS@La2O3 is well accordant with the pseudo-second order kinetics equation, indicating that it is dominated by the chemical adsorption. The adsorption reaction could be explained by the "surface hydroxylation-ion exchange" model on the La2O3 surface. The used CMS@La2O3 adsorbent could be recycled for several times after appropriate treatment.
2018, 34(8): 1463-1469
doi: 10.11862/CJIC.2018.172
Abstract:
Graphene oxide prepared by modified Hummers was modified by ethylenediamine, ethylenediamine and butanediamine/hexamethylenediamine miscibility. Fe3O4 was prepared by hydrothermal, and GO/Fe3O4/organic amine ternary complex system was prepared by physical mixing. The prepared samples were characterized by TEM, SEM, FT-IR, TG, XRD, VSM and XPS, the performance of ternary composite particles on the crystal violet dye adsorption was tested, and the adsorption properties of the ternary composite particles on the crystal violet dyes were studied. The results show that the prepared Fe3O4 have an average particle size of about 200 nm and a uniform particle size distribution; the graphene in the composite is a typical sheet-like structure; the doping of graphene and organic amine does not affect the spinel of Fe3O4 structure; the composite is superparamagnetic with Ms of 53.0 emu·g-1. The results of adsorption showed that the maximum adsorption capacity of the ternary composite on the crystal violet dye increases with the increase of concentration, while the removal rate of crystal violet dye adsorption increases with the concentration of crystal violet dye decrease, and tend to a certain value. The best adsorption capacity of GO/Fe3O4 composites with 5:1 miscibility of ethylenediamine and hexamethylenediamine is:mass concentration of the crystal violet=400 mg·L-1, maximum adsorption=164.3 mg·L-1.
Graphene oxide prepared by modified Hummers was modified by ethylenediamine, ethylenediamine and butanediamine/hexamethylenediamine miscibility. Fe3O4 was prepared by hydrothermal, and GO/Fe3O4/organic amine ternary complex system was prepared by physical mixing. The prepared samples were characterized by TEM, SEM, FT-IR, TG, XRD, VSM and XPS, the performance of ternary composite particles on the crystal violet dye adsorption was tested, and the adsorption properties of the ternary composite particles on the crystal violet dyes were studied. The results show that the prepared Fe3O4 have an average particle size of about 200 nm and a uniform particle size distribution; the graphene in the composite is a typical sheet-like structure; the doping of graphene and organic amine does not affect the spinel of Fe3O4 structure; the composite is superparamagnetic with Ms of 53.0 emu·g-1. The results of adsorption showed that the maximum adsorption capacity of the ternary composite on the crystal violet dye increases with the increase of concentration, while the removal rate of crystal violet dye adsorption increases with the concentration of crystal violet dye decrease, and tend to a certain value. The best adsorption capacity of GO/Fe3O4 composites with 5:1 miscibility of ethylenediamine and hexamethylenediamine is:mass concentration of the crystal violet=400 mg·L-1, maximum adsorption=164.3 mg·L-1.
2018, 34(8): 1470-1476
doi: 10.11862/CJIC.2018.180
Abstract:
γ-AlOOH nanrods were firstly prepared via a hydrothermal method, and then Pt/γ-AlOOH nanrods catalysts (PA) were obtained by a combined impregnation and NaBH4-reduction method using γ-AlOOH nanrods as supports. The obtained PA was used to catalytically oxidize formaldehyde (HCHO) at room temperature and the effect of Pt content on catalytic activity was also studied. The prepared samples were characterized by XRD, TEM, XPS and N2 adsorption-desorption isothermal test. The results show that PA reveals higher catalytic acitivity than Pt/γ-Al2O3, which is mainly due to the abundance of surface hydroxyls and high dispersion of Pt nanoparticles. The catalytic activities of PA firstly increase and then almost maintain unchanged with increasing of Pt content in the range of 0.05%~0.5% (w/w). 0.2% (w/w) Pt is the optimum loading considering both catalytic activity and cost.
γ-AlOOH nanrods were firstly prepared via a hydrothermal method, and then Pt/γ-AlOOH nanrods catalysts (PA) were obtained by a combined impregnation and NaBH4-reduction method using γ-AlOOH nanrods as supports. The obtained PA was used to catalytically oxidize formaldehyde (HCHO) at room temperature and the effect of Pt content on catalytic activity was also studied. The prepared samples were characterized by XRD, TEM, XPS and N2 adsorption-desorption isothermal test. The results show that PA reveals higher catalytic acitivity than Pt/γ-Al2O3, which is mainly due to the abundance of surface hydroxyls and high dispersion of Pt nanoparticles. The catalytic activities of PA firstly increase and then almost maintain unchanged with increasing of Pt content in the range of 0.05%~0.5% (w/w). 0.2% (w/w) Pt is the optimum loading considering both catalytic activity and cost.
2018, 34(8): 1477-1482
doi: 10.11862/CJIC.2018.173
Abstract:
The hydrothermal synthesis of MOR/SBA-15 composite zeolite has been achieved by employing MOR nanocrystalline and tetraethyl orthosilicate (TEOS) as silica source, and triblock copolymer P123 as hard template. The catalyst was characterized through an integrated method including XRD, SEM, TEM and EDX, and the corresponding catalytic performance was evaluated in the conversion of diethyl ether (DME) to ethanol in a fixed-bed reactor. The results show that MOR nanocrystalline, a building unit for SBA-15, can be successfully grafted in the mesopore framework of SBA-15 by controlling the addition of MOR nanocrystalline. The obtained composite zeolite possesses both the characteristic diffraction peaks of MOR and SBA-15. The specific surface area and total pore volume, compared with SBA-15, decrease from 756 m2·g-1, 1.07 m3·g-1 to 628 m2·g-1, 0.85 m3·g-1, respectively. And the pore diameter in average raises from 8.1 to 9.3 nm. An extra Cu modification of the composite zeolite allows a bifunctional catalytic performance of carbonylation with CuMOR and hydrogenation with CuSBA-15. The catalyst evaluation tests show that the conversion of DME is 43.6% and the selectivity to ethanol is 95.3%, indicating a one-step transformation from DME to ethanol over CuMOR/SBA-15 composite zeolite.
The hydrothermal synthesis of MOR/SBA-15 composite zeolite has been achieved by employing MOR nanocrystalline and tetraethyl orthosilicate (TEOS) as silica source, and triblock copolymer P123 as hard template. The catalyst was characterized through an integrated method including XRD, SEM, TEM and EDX, and the corresponding catalytic performance was evaluated in the conversion of diethyl ether (DME) to ethanol in a fixed-bed reactor. The results show that MOR nanocrystalline, a building unit for SBA-15, can be successfully grafted in the mesopore framework of SBA-15 by controlling the addition of MOR nanocrystalline. The obtained composite zeolite possesses both the characteristic diffraction peaks of MOR and SBA-15. The specific surface area and total pore volume, compared with SBA-15, decrease from 756 m2·g-1, 1.07 m3·g-1 to 628 m2·g-1, 0.85 m3·g-1, respectively. And the pore diameter in average raises from 8.1 to 9.3 nm. An extra Cu modification of the composite zeolite allows a bifunctional catalytic performance of carbonylation with CuMOR and hydrogenation with CuSBA-15. The catalyst evaluation tests show that the conversion of DME is 43.6% and the selectivity to ethanol is 95.3%, indicating a one-step transformation from DME to ethanol over CuMOR/SBA-15 composite zeolite.
2018, 34(8): 1483-1488
doi: 10.11862/CJIC.2018.171
Abstract:
Submicron barium titanate with spherical morphology was synthesized at relatively low temperature by using barium hydroxide octahydrate and α-titanic acid as starting materials. Barium titanate samples were characterized by XRD, SEM, Raman and FTIR, and the results show that the samples have high crystallinity and good uniformity. Tetragonal phase-based barium titanate can be obtained by phase transition from cubic phase-based barium titanate at low temperatue of 400℃. The preliminarily results of phase transition study were indicated.
Submicron barium titanate with spherical morphology was synthesized at relatively low temperature by using barium hydroxide octahydrate and α-titanic acid as starting materials. Barium titanate samples were characterized by XRD, SEM, Raman and FTIR, and the results show that the samples have high crystallinity and good uniformity. Tetragonal phase-based barium titanate can be obtained by phase transition from cubic phase-based barium titanate at low temperatue of 400℃. The preliminarily results of phase transition study were indicated.
2018, 34(8): 1489-1493
doi: 10.11862/CJIC.2018.184
Abstract:
CH3NH3PbBr3 nanoplatelets were synthesized via a hot-injection method. Red shift from 451 to 531 nm of the photoluminescence (PL) spectrum was found after different folds of dilution. The results of TEM and XRD show that red shift is caused by the growth of particles for the aggregation self-assembly of CH3NH3PbBr3 nanoplatelets. The contrast experiments prove that oleylamine plays an important part in the aggregation self-assembly of nanoplatelets. The aggregation self-assembly mechanism of CH3NH3PbBr3 nanoplatelets is elaborated combining the results of XRD and TEM.
CH3NH3PbBr3 nanoplatelets were synthesized via a hot-injection method. Red shift from 451 to 531 nm of the photoluminescence (PL) spectrum was found after different folds of dilution. The results of TEM and XRD show that red shift is caused by the growth of particles for the aggregation self-assembly of CH3NH3PbBr3 nanoplatelets. The contrast experiments prove that oleylamine plays an important part in the aggregation self-assembly of nanoplatelets. The aggregation self-assembly mechanism of CH3NH3PbBr3 nanoplatelets is elaborated combining the results of XRD and TEM.
2018, 34(8): 1494-1500
doi: 10.11862/CJIC.2018.186
Abstract:
Ni/NiFe2O4 nanorods encapsulated in onion-like N-doped carbon (ONC) nanolayers was prepared by the pyrolysis of NiFe-based coordination polymer precursor under N2 atmosphere. Compared with Ni@ONC, NiFe2O4, and commercial RuO2 electrocatalysts, benefiting by the promoted electronic conductivity and enlarged electrochemical surface area (0.149 mF) from synergistic effects between the ONC nanolayers and encapsulated Ni/NiFe2O4 heterostructure, the as-prepared Ni/NiFe2O4@ONC hybrid nanorod exhibits extraordinary electrocatalytic activity towards oxygen evolution reaction (OER) with an overpotential of~299 mV at 10 mA·cm-2 and a Tafel slope of 73 mV·dec-1.
Ni/NiFe2O4 nanorods encapsulated in onion-like N-doped carbon (ONC) nanolayers was prepared by the pyrolysis of NiFe-based coordination polymer precursor under N2 atmosphere. Compared with Ni@ONC, NiFe2O4, and commercial RuO2 electrocatalysts, benefiting by the promoted electronic conductivity and enlarged electrochemical surface area (0.149 mF) from synergistic effects between the ONC nanolayers and encapsulated Ni/NiFe2O4 heterostructure, the as-prepared Ni/NiFe2O4@ONC hybrid nanorod exhibits extraordinary electrocatalytic activity towards oxygen evolution reaction (OER) with an overpotential of~299 mV at 10 mA·cm-2 and a Tafel slope of 73 mV·dec-1.
2018, 34(8): 1501-1510
doi: 10.11862/CJIC.2018.190
Abstract:
The LiFePO4-Graphene/LiNi0.8Co0.15Al0.05O2 composite for lithium ion batteries has been prepared by a two-step dry-mixing and ball-milling procedure to achieve high capacity and high security of LiNi0.8Co0.15Al0.05O2. The crystalline structure, morphology and electrochemical performance were systematically characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM), X-ray photoelectronic spectroscopy (XPS) and electrochemical tests. With the addition of graphene, the LiFePO4 nanoparticles can cover the surface of LiNi0.8Co0.15Al0.05O2 tightly, further protecting LiNi0.8Co0.15Al0.05O2 from the side reaction with electrolyte, increasing the utilization of active materials and enhancing the cycling performance. The conductive networks consisted of LiNi0.8Co0.15Al0.05O2, LiFePO4 and graphene can facilitate electron infiltration and transport, thus improving the rate performance. The LiFePO4-Graphene/LiNi0.8Co0.15Al0.05O2 composite with 20% (w/w) LiFePO4 content exhibits a reversible capacitance up to 202.5 mAh·g-1 at 0.1C, good rate capability with 160.5 mAh·g-1 at 3C, and an excellent long-term cycling stability with 91.9% capacity retention after 100 cycles at 50℃, which is much better than 72.9% of the pristine LiNi0.8Co0.15Al0.05O2 and 82.0% of the LiFePO4/LiNi0.8Co0.15Al0.05O2 composite.
The LiFePO4-Graphene/LiNi0.8Co0.15Al0.05O2 composite for lithium ion batteries has been prepared by a two-step dry-mixing and ball-milling procedure to achieve high capacity and high security of LiNi0.8Co0.15Al0.05O2. The crystalline structure, morphology and electrochemical performance were systematically characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM), X-ray photoelectronic spectroscopy (XPS) and electrochemical tests. With the addition of graphene, the LiFePO4 nanoparticles can cover the surface of LiNi0.8Co0.15Al0.05O2 tightly, further protecting LiNi0.8Co0.15Al0.05O2 from the side reaction with electrolyte, increasing the utilization of active materials and enhancing the cycling performance. The conductive networks consisted of LiNi0.8Co0.15Al0.05O2, LiFePO4 and graphene can facilitate electron infiltration and transport, thus improving the rate performance. The LiFePO4-Graphene/LiNi0.8Co0.15Al0.05O2 composite with 20% (w/w) LiFePO4 content exhibits a reversible capacitance up to 202.5 mAh·g-1 at 0.1C, good rate capability with 160.5 mAh·g-1 at 3C, and an excellent long-term cycling stability with 91.9% capacity retention after 100 cycles at 50℃, which is much better than 72.9% of the pristine LiNi0.8Co0.15Al0.05O2 and 82.0% of the LiFePO4/LiNi0.8Co0.15Al0.05O2 composite.
2018, 34(8): 1511-1516
doi: 10.11862/CJIC.2018.196
Abstract:
Two complexes[NiL(HL)](OAc) (1) and[ZnL(OAc)]n (2) (HL=1-(3-ethylpyrazin-2-yl)ethylidene)-4-methylthiosemicarbazide) have been synthesized and structurally determined by single-crystal X-ray diffraction. The results show that the Ni(Ⅱ) ion in 1 is surrounded by two independent thiosemicarbazone ligands with N4S2 donor set, one of which is anionic. However, in complex 2, the Zn(Ⅱ) ion with a distorted tetragonal pyramid coordination geometry is five-coordinated, involving two μ-OCO acetate anions, one tridentate enolizated ligand L-, thus forming one dimension chain-like framework along a axis. Moreover, the fluorescence spectra indicate that the interactions of the complexes with DNA are stronger than that of the thiosemicarbazone ligand.
Two complexes[NiL(HL)](OAc) (1) and[ZnL(OAc)]n (2) (HL=1-(3-ethylpyrazin-2-yl)ethylidene)-4-methylthiosemicarbazide) have been synthesized and structurally determined by single-crystal X-ray diffraction. The results show that the Ni(Ⅱ) ion in 1 is surrounded by two independent thiosemicarbazone ligands with N4S2 donor set, one of which is anionic. However, in complex 2, the Zn(Ⅱ) ion with a distorted tetragonal pyramid coordination geometry is five-coordinated, involving two μ-OCO acetate anions, one tridentate enolizated ligand L-, thus forming one dimension chain-like framework along a axis. Moreover, the fluorescence spectra indicate that the interactions of the complexes with DNA are stronger than that of the thiosemicarbazone ligand.
2018, 34(8): 1517-1530
doi: 10.11862/CJIC.2018.199
Abstract:
Selenium doped hydroxyapatite microspheres (HASe) were prepared by using self-sacrificing CaCO3 as template via hydrothermal route, and their physicochemical properties were characterized by SEM, TEM, DLS, XRD, FTIR and TGA. The curcumin was employed as the model drug, and its delivery behavior from HASe microspheres was evaluated with the loading efficacy and controlled-release efficiency. As a result, it was observed that the synthetic HASe products are spherical with an average diameter of about 1.0 μm. The surface of the microspheres is constructed by subtle units of hydroxyapatite nanorods which are 150 nm in length and 20 nm in width. HASe microspheres exhibit a high drug loading efficacy and slowly sustainable release behavior for curcumin. The loading amount of HASe10 was (88.72±0.01) mg·g-1, and less than 1.5 mg of curcumin was released from it during 0~159 h. There is no burst release but slow sustainable release manner in it. Moreover, the toxicity of HASe microspheres was investigated by blood assay and cell experiment. Compared with selenium-free HA microspheres, HASe microspheres show lower blood toxicity to healthy man, and less damage to normal cells, but stronger inhibition on the growth of the osteosarcoma cells.
Selenium doped hydroxyapatite microspheres (HASe) were prepared by using self-sacrificing CaCO3 as template via hydrothermal route, and their physicochemical properties were characterized by SEM, TEM, DLS, XRD, FTIR and TGA. The curcumin was employed as the model drug, and its delivery behavior from HASe microspheres was evaluated with the loading efficacy and controlled-release efficiency. As a result, it was observed that the synthetic HASe products are spherical with an average diameter of about 1.0 μm. The surface of the microspheres is constructed by subtle units of hydroxyapatite nanorods which are 150 nm in length and 20 nm in width. HASe microspheres exhibit a high drug loading efficacy and slowly sustainable release behavior for curcumin. The loading amount of HASe10 was (88.72±0.01) mg·g-1, and less than 1.5 mg of curcumin was released from it during 0~159 h. There is no burst release but slow sustainable release manner in it. Moreover, the toxicity of HASe microspheres was investigated by blood assay and cell experiment. Compared with selenium-free HA microspheres, HASe microspheres show lower blood toxicity to healthy man, and less damage to normal cells, but stronger inhibition on the growth of the osteosarcoma cells.
2018, 34(8): 1531-1537
doi: 10.11862/CJIC.2018.169
Abstract:
Fluorescent molecularly imprinted polymers(FMIPs) for selective determination 2, 4, 6-trichlorophenol were devised and fabricated. Here, europium(Ⅲ) complexes were used as fluorescence detection tool via the fluorescence quenching with templates. The FMIPs have a linear fluorescent response in 0~70 nmol·L-1 concentration range, and the correlation coefficient was 0.996 28. The FMIPs exhibit excellent sensitivity with the limit of detection of 3.12 nmol·L-1. In addition, FMIPs show good thermal stability and appreciable selectivity over several analogues. The experimental results showed that FMIPs could be used for selective fluorescence detection of low concentrations of chlorophenols.
Fluorescent molecularly imprinted polymers(FMIPs) for selective determination 2, 4, 6-trichlorophenol were devised and fabricated. Here, europium(Ⅲ) complexes were used as fluorescence detection tool via the fluorescence quenching with templates. The FMIPs have a linear fluorescent response in 0~70 nmol·L-1 concentration range, and the correlation coefficient was 0.996 28. The FMIPs exhibit excellent sensitivity with the limit of detection of 3.12 nmol·L-1. In addition, FMIPs show good thermal stability and appreciable selectivity over several analogues. The experimental results showed that FMIPs could be used for selective fluorescence detection of low concentrations of chlorophenols.
2018, 34(8): 1538-1546
doi: 10.11862/CJIC.2018.168
Abstract:
Different morphologies (rod-like and sheet-like) of CeOHCO3 were controllably synthesized by using 2, 4-dihydroxybenzonic acid (DHBA) as auxiliary. During the hydrothermal process, the morphologies of CeOHCO3 were controlled by adding different amount of DHBA. When the amount of DHBA was 3.5 mmol, rod-like CeOHCO3 was synthesized, while by increasing the amount of DHBA to 5.0 mmol, the sheet-like CeOHCO3 was relatively generated. Then the rod-like and sheet-like fcc-CeO2 (face-centered cubic-CeO2) were successfully obtained by the subsequent calcination procedure. The resulted CeO2 affords large surface area (> 60 m2·g-1), while the rod-like CeO2 exhibits higher redox ability and more acid amount compared to those of sheet-like CeO2. In addition, the rod-like CeO2 exhibits better catalytic activity in NH3-SCR.
Different morphologies (rod-like and sheet-like) of CeOHCO3 were controllably synthesized by using 2, 4-dihydroxybenzonic acid (DHBA) as auxiliary. During the hydrothermal process, the morphologies of CeOHCO3 were controlled by adding different amount of DHBA. When the amount of DHBA was 3.5 mmol, rod-like CeOHCO3 was synthesized, while by increasing the amount of DHBA to 5.0 mmol, the sheet-like CeOHCO3 was relatively generated. Then the rod-like and sheet-like fcc-CeO2 (face-centered cubic-CeO2) were successfully obtained by the subsequent calcination procedure. The resulted CeO2 affords large surface area (> 60 m2·g-1), while the rod-like CeO2 exhibits higher redox ability and more acid amount compared to those of sheet-like CeO2. In addition, the rod-like CeO2 exhibits better catalytic activity in NH3-SCR.
