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2021 Volume 37 Issue 12
2021, 37(12): 2113-2124
doi: 10.11862/CJIC.2021.258
Abstract:
Accurate quantitative detection of ethanol (EtOH) content is essential for environmental monitoring, clinical diagnosis, food testing, and drinking alcohol. A simple and green fluorescence colorimetry method utilizing sonochemical reduction method for the rapid and efficient detection of EtOH in alcoholic beverages has been established. The fluorescent copper nanoclusters (PVP-Cu NCs) were synthesized by using CuCl2 as a copper source, 2-mercaptobenzothiazole (MBT) as a stabilizing agent, polyvinylpyrrolidone (PVP) as a protecting agent and ascorbic acid (AA) as a reducing agent. The resultant PVP-Cu NCs had a spherical shape with an average diameter of 6.0 nm and a strong fluorescent orange emission characteristic peak at 580 nm upon 340 nm excitation. The fluorescence copper nanoclusters possessed the advantages of excellent time, ultraviolet radiation and salt resistance stability. We found that PVP-Cu NCs had a good responsiveness to EtOH, and the fluorescence intensity was inversely proportionate to the EtOH volume fractions between 5% and 45% as a consequence of inducing aggregation of PVP-Cu NCs via changing its double layer and affecting its stability in the studied system. Based on the established calibration, the EtOH content was effectively evaluated with good precision. Furthermore, visible color transformation of this sensor paper was observed in the EtOH content range of 20%-60%, implying utility for visual EtOH detection. It is worth mentioning that the assay was successfully applied for the quantification of EtOH in commercial drink samples and the satisfying results were obtained.
Accurate quantitative detection of ethanol (EtOH) content is essential for environmental monitoring, clinical diagnosis, food testing, and drinking alcohol. A simple and green fluorescence colorimetry method utilizing sonochemical reduction method for the rapid and efficient detection of EtOH in alcoholic beverages has been established. The fluorescent copper nanoclusters (PVP-Cu NCs) were synthesized by using CuCl2 as a copper source, 2-mercaptobenzothiazole (MBT) as a stabilizing agent, polyvinylpyrrolidone (PVP) as a protecting agent and ascorbic acid (AA) as a reducing agent. The resultant PVP-Cu NCs had a spherical shape with an average diameter of 6.0 nm and a strong fluorescent orange emission characteristic peak at 580 nm upon 340 nm excitation. The fluorescence copper nanoclusters possessed the advantages of excellent time, ultraviolet radiation and salt resistance stability. We found that PVP-Cu NCs had a good responsiveness to EtOH, and the fluorescence intensity was inversely proportionate to the EtOH volume fractions between 5% and 45% as a consequence of inducing aggregation of PVP-Cu NCs via changing its double layer and affecting its stability in the studied system. Based on the established calibration, the EtOH content was effectively evaluated with good precision. Furthermore, visible color transformation of this sensor paper was observed in the EtOH content range of 20%-60%, implying utility for visual EtOH detection. It is worth mentioning that the assay was successfully applied for the quantification of EtOH in commercial drink samples and the satisfying results were obtained.
2021, 37(12): 2125-2132
doi: 10.11862/CJIC.2021.250
Abstract:
A series of cyclometalated iridium(Ⅲ) complexes, [(dfppy)2Ir(bpy-sugar)]Cl (1), [(tpy-COOH)2Ir(bpy-sugar)] Cl (2) and[(mpbq)2Ir(bpy-sugar)]Cl (3) (dfppy=2-(2, 4-difluorophenyl)pyridine, tpy-COOH=4-(2'-pyridyl)benzoic acid, mpbq=2-methyl-3-phenylbenzo[g]quinoxaline, bpy-sugar=4, 4'-bis(1-thio-β-D-glucosemethyl)-2, 2'-bipyridine), were designed and synthesized with cyclometalated C^N ligand and bpy-sugar assistant ligands. Their structures were characterized by NMR, MS, IR spectroscopy and elemental analysis. Their photophysical properties and applications in cell imaging were studied. Through the regulation of auxiliary cyclometalated ligands, the photoluminescence of the complexes can be tuned from yellow to near-infrared light. In aqueous solution, complexes 1 and 2 displayed yellow emissions with the maximum wavelengths at about 546 and 584 nm, respectively. While complex 3 displayed near infrared emission with wavelength at about 780 nm in a mixed solution of H2O and dimethyl sulfoxide (39:1, V/V). The quantum efficiencies of complexes 1 and 2 were 16.9% and 3.1%, respectively. The quantum yield of complex 1 was significantly higher than that of ruthenium(Ⅱ) tris(2, 2'-bipyridine). The photoluminescence of complex 3 was weak, and the integrating sphere cannot obtain accurate quantum yield. However, its photoluminescence in the near-infrared region was expected to be used as a near-infrared probe for biological analysis. The lifetimes of complexes 1 and 2 were 0.22 and 0.10 μs, respectively. Modifying different groups on the ligand can increase the cell penetration and water solubility of the complexes, and realize the imaging analysis of the complex in the cell. The iridium(Ⅲ) complexes could penetrate the cell membrane and enter the cell, and overlap with the part of the nucleus stained by 4, 6-bialamidine-2-phenylindole (DAPI), indicating that it had entered the nucleus. The photoluminescence of the iridium(Ⅲ) complexes was good in living cells, showing that the iridium(Ⅲ) complexes was still stable in the biological environment.
A series of cyclometalated iridium(Ⅲ) complexes, [(dfppy)2Ir(bpy-sugar)]Cl (1), [(tpy-COOH)2Ir(bpy-sugar)] Cl (2) and[(mpbq)2Ir(bpy-sugar)]Cl (3) (dfppy=2-(2, 4-difluorophenyl)pyridine, tpy-COOH=4-(2'-pyridyl)benzoic acid, mpbq=2-methyl-3-phenylbenzo[g]quinoxaline, bpy-sugar=4, 4'-bis(1-thio-β-D-glucosemethyl)-2, 2'-bipyridine), were designed and synthesized with cyclometalated C^N ligand and bpy-sugar assistant ligands. Their structures were characterized by NMR, MS, IR spectroscopy and elemental analysis. Their photophysical properties and applications in cell imaging were studied. Through the regulation of auxiliary cyclometalated ligands, the photoluminescence of the complexes can be tuned from yellow to near-infrared light. In aqueous solution, complexes 1 and 2 displayed yellow emissions with the maximum wavelengths at about 546 and 584 nm, respectively. While complex 3 displayed near infrared emission with wavelength at about 780 nm in a mixed solution of H2O and dimethyl sulfoxide (39:1, V/V). The quantum efficiencies of complexes 1 and 2 were 16.9% and 3.1%, respectively. The quantum yield of complex 1 was significantly higher than that of ruthenium(Ⅱ) tris(2, 2'-bipyridine). The photoluminescence of complex 3 was weak, and the integrating sphere cannot obtain accurate quantum yield. However, its photoluminescence in the near-infrared region was expected to be used as a near-infrared probe for biological analysis. The lifetimes of complexes 1 and 2 were 0.22 and 0.10 μs, respectively. Modifying different groups on the ligand can increase the cell penetration and water solubility of the complexes, and realize the imaging analysis of the complex in the cell. The iridium(Ⅲ) complexes could penetrate the cell membrane and enter the cell, and overlap with the part of the nucleus stained by 4, 6-bialamidine-2-phenylindole (DAPI), indicating that it had entered the nucleus. The photoluminescence of the iridium(Ⅲ) complexes was good in living cells, showing that the iridium(Ⅲ) complexes was still stable in the biological environment.
2021, 37(12): 2133-2140
doi: 10.11862/CJIC.2021.254
Abstract:
Complexes[Zn(L)2(4, 4'-bipy)(H2O)]n (1) and[Zn(L)(2, 2'-bipy)]n (2) were synthesized by solvothermal reaction of 2, 5-bis(trifluoromethyl) terephthalic acid (H2L) as main ligand and zinc chloride as metal salt with auxiliary ligands 4, 4'-bipyridine (4, 4'-bipy) and 2, 2'-bipyridine (2, 2'-bipy), respectively. Their structure and properties were characterized by X-ray single crystal diffraction, FT-IR, elemental analysis, thermogravimetric analysis, etc. The results show that complex 1 forms an infinitely extending two-dimensional network structure by the bridging effect of L2- and 4, 4'-bipy ligands, and the layers are stacked in an orderly manner under the action of O5-H5B…O1 hydrogen bond developing three-dimensional structure. The Zn2+ acts as the metal node in complex 2, and each carboxyl group on L2- bridges zinc ions through bidentate chelation and connects infinitely to form a 3D network structure.
Complexes[Zn(L)2(4, 4'-bipy)(H2O)]n (1) and[Zn(L)(2, 2'-bipy)]n (2) were synthesized by solvothermal reaction of 2, 5-bis(trifluoromethyl) terephthalic acid (H2L) as main ligand and zinc chloride as metal salt with auxiliary ligands 4, 4'-bipyridine (4, 4'-bipy) and 2, 2'-bipyridine (2, 2'-bipy), respectively. Their structure and properties were characterized by X-ray single crystal diffraction, FT-IR, elemental analysis, thermogravimetric analysis, etc. The results show that complex 1 forms an infinitely extending two-dimensional network structure by the bridging effect of L2- and 4, 4'-bipy ligands, and the layers are stacked in an orderly manner under the action of O5-H5B…O1 hydrogen bond developing three-dimensional structure. The Zn2+ acts as the metal node in complex 2, and each carboxyl group on L2- bridges zinc ions through bidentate chelation and connects infinitely to form a 3D network structure.
2021, 37(12): 2141-2148
doi: 10.11862/CJIC.2021.245
Abstract:
Sol-gel method was applied to prepare BiVO4 (BV) and Nd0.2Ce0.8O1.9 (NDC) powders. The effects of BV doping on microstructure, morphology and electrical properties of NDC electrolyte were studied. The results of experiments revealed that Nd0.2Ce0.8O1.9 electrolyte showed a highly dense microstructure. At 700℃, the total conductivity (σt) of NDC-5BV electrolyte was 3.35×10-2 S·cm-1. The polarization resistance (Rp) was reduced by more than 34% at 700℃. The maximum power density (MPD) of the single cell reached up to 514 mW·cm-2 at 700℃. During the operation time for 70 h, the open circuit voltage (OCV) can be maintained good stability.
Sol-gel method was applied to prepare BiVO4 (BV) and Nd0.2Ce0.8O1.9 (NDC) powders. The effects of BV doping on microstructure, morphology and electrical properties of NDC electrolyte were studied. The results of experiments revealed that Nd0.2Ce0.8O1.9 electrolyte showed a highly dense microstructure. At 700℃, the total conductivity (σt) of NDC-5BV electrolyte was 3.35×10-2 S·cm-1. The polarization resistance (Rp) was reduced by more than 34% at 700℃. The maximum power density (MPD) of the single cell reached up to 514 mW·cm-2 at 700℃. During the operation time for 70 h, the open circuit voltage (OCV) can be maintained good stability.
2021, 37(12): 2149-2157
doi: 10.11862/CJIC.2021.255
Abstract:
Two quaternary chalcogenides Rb2CdSbS3(SH) (1) and Rb2HgSb4S8 (2) were synthesized by solvothermal method. Single crystal X-ray diffraction analysis shows that compound 1 is 1D chain structure and composed of[CdSbS3(SH)]2- anion and Rb+ cation. Compound 2 is a 2D layered structure and composed of[HgSb4S8]2- anion and Rb+ cation. Solid-state UV-Vis diffuse reflectance spectra showed that the band gaps of compounds 1 and 2 were 2.06 and 2.15 eV, respectively. Fluorescence analysis showed that compounds 1 and 2 had yellow emission characteristics.
Two quaternary chalcogenides Rb2CdSbS3(SH) (1) and Rb2HgSb4S8 (2) were synthesized by solvothermal method. Single crystal X-ray diffraction analysis shows that compound 1 is 1D chain structure and composed of[CdSbS3(SH)]2- anion and Rb+ cation. Compound 2 is a 2D layered structure and composed of[HgSb4S8]2- anion and Rb+ cation. Solid-state UV-Vis diffuse reflectance spectra showed that the band gaps of compounds 1 and 2 were 2.06 and 2.15 eV, respectively. Fluorescence analysis showed that compounds 1 and 2 had yellow emission characteristics.
2021, 37(12): 2158-2166
doi: 10.11862/CJIC.2021.252
Abstract:
Upconversion nanoparticles NaYF4: 20%Yb, 2%Er@NaYF4 (marked as UCNP) and gold nanoparticles (AuNP) were used as donors and acceptors to study non-radiative energy transfer in an assembly structure with a defined position relationship. Using UCNP and AuNP as basic building units, two-dimensional UCNP monolayer with large area and regular arrangement were self-assembled by solvent evaporation method at liquid-air interface. UCNP+AuNP bilayer and UCNP+NaYF4+AuNP trilayer structures were prepared by layer-by-layer assembly. Then the luminescent properties of self-assembled films were characterized by the spectral imager system which was designed by our group. The spectrum of three kinds of films were compared. It was found that the luminescence attenuation of UCNP+AuNP bilayer structure and UCNP+NaYF4+AuNP trilayer structure were similar, compared with UCNP monolayer. That is, there is no obvious non-radiative energy transfer between UCNP and AuNP in our research system. In the research, a well-geometric assembly model was provided, and the luminescence test equipment was set up, and it was verified that there was no non-radiative energy transfer between UCNP and AuNP in our self-assembly models.
Upconversion nanoparticles NaYF4: 20%Yb, 2%Er@NaYF4 (marked as UCNP) and gold nanoparticles (AuNP) were used as donors and acceptors to study non-radiative energy transfer in an assembly structure with a defined position relationship. Using UCNP and AuNP as basic building units, two-dimensional UCNP monolayer with large area and regular arrangement were self-assembled by solvent evaporation method at liquid-air interface. UCNP+AuNP bilayer and UCNP+NaYF4+AuNP trilayer structures were prepared by layer-by-layer assembly. Then the luminescent properties of self-assembled films were characterized by the spectral imager system which was designed by our group. The spectrum of three kinds of films were compared. It was found that the luminescence attenuation of UCNP+AuNP bilayer structure and UCNP+NaYF4+AuNP trilayer structure were similar, compared with UCNP monolayer. That is, there is no obvious non-radiative energy transfer between UCNP and AuNP in our research system. In the research, a well-geometric assembly model was provided, and the luminescence test equipment was set up, and it was verified that there was no non-radiative energy transfer between UCNP and AuNP in our self-assembly models.
2021, 37(12): 2167-2174
doi: 10.11862/CJIC.2021.219
Abstract:
The adsorption and diffusion behaviors of Li-ion on boron-doped MoSi2N4 monolayer were studied by ultrasoft pseudopotential plane-wave method. We established three physical models: substitution sites, interstitial sites and adsorption sites of boron-doped MoSi2N4 monolayer, including six doped configurations. The results show that boron substitution for nitrogen on the surface is the most stable, and the adsorption energy of Li-ion on the configuration is between -1.540 and -1.910 eV. The charge density difference diagram indicates that both boron and nitrogen on the surface accept part of electrons from the Li-ion, which leads to the enhancement of adsorption energy. According to the potential energy difference of Li-ion adsorption on the surface of boron-doped MoSi2N4, it concludes that the diffusion pathway is D→F and the corresponding diffusion barrier is 0.077 eV, it is confirmed that the Li-ion has high extraction-insertion rate on the surface of boron-doped MoSi2N4 monolayer.
The adsorption and diffusion behaviors of Li-ion on boron-doped MoSi2N4 monolayer were studied by ultrasoft pseudopotential plane-wave method. We established three physical models: substitution sites, interstitial sites and adsorption sites of boron-doped MoSi2N4 monolayer, including six doped configurations. The results show that boron substitution for nitrogen on the surface is the most stable, and the adsorption energy of Li-ion on the configuration is between -1.540 and -1.910 eV. The charge density difference diagram indicates that both boron and nitrogen on the surface accept part of electrons from the Li-ion, which leads to the enhancement of adsorption energy. According to the potential energy difference of Li-ion adsorption on the surface of boron-doped MoSi2N4, it concludes that the diffusion pathway is D→F and the corresponding diffusion barrier is 0.077 eV, it is confirmed that the Li-ion has high extraction-insertion rate on the surface of boron-doped MoSi2N4 monolayer.
2021, 37(12): 2175-2184
doi: 10.11862/CJIC.2021.234
Abstract:
MnO2/CC and N doped MnO2/CC binderless anode materials were prepared by hydrothermal method with carbon cloth (CC) as a flexible substrate, and the structure characterization and electrochemical performance of the materials were tested by means of X-ray diffraction (XRD), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), specific surface area test and galvanostatic charge and discharge. The results showed that N doped MnO2/CC had good rate performance and cycle stability. The first charge specific capacity of N doped MnO2/CC was 948.8 mAh·g-1 at the current density of 0.1 A·g-1, and the reversible specific capacity remained 907.9 mAh·g-1 when the current density returned to 0.1 A·g-1 after different rate tests, and the capacity retention rate was 95.7%. At the high current density of 1 A·g-1, the initial charging specific capacity of N doped MnO2/CC was 640.3 mAh·g-1, the reversible specific capacity still retained 529.9 mAh·g-1 after 100 cycles, and the capacity retention rate was 82.8%. The reversible specific capacity was much higher than that of commercial MnO2.
MnO2/CC and N doped MnO2/CC binderless anode materials were prepared by hydrothermal method with carbon cloth (CC) as a flexible substrate, and the structure characterization and electrochemical performance of the materials were tested by means of X-ray diffraction (XRD), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), specific surface area test and galvanostatic charge and discharge. The results showed that N doped MnO2/CC had good rate performance and cycle stability. The first charge specific capacity of N doped MnO2/CC was 948.8 mAh·g-1 at the current density of 0.1 A·g-1, and the reversible specific capacity remained 907.9 mAh·g-1 when the current density returned to 0.1 A·g-1 after different rate tests, and the capacity retention rate was 95.7%. At the high current density of 1 A·g-1, the initial charging specific capacity of N doped MnO2/CC was 640.3 mAh·g-1, the reversible specific capacity still retained 529.9 mAh·g-1 after 100 cycles, and the capacity retention rate was 82.8%. The reversible specific capacity was much higher than that of commercial MnO2.
2021, 37(12): 2185-2192
doi: 10.11862/CJIC.2021.246
Abstract:
The cathode material La2-xBixCuO4 (x=0, 0.05, 0.10) for solid oxide fuel cell was synthesized by glycinenitrate method. The phase of the material was analyzed by X-ray diffraction (XRD) method. The results show that the material crystallizes in peroskite-type single phase oxide. Due to the increase doping amount of bismuth, the space group of the material changes from Fmmm to I4/mmm. The unit cell volume increases with the doping amount of bismuth. La2-xBixCuO4 cathode materials were found to show no chemical reaction with the electrolyte Sm0.2Ce0.8O1.9 (SDC) at 950℃ for 24 h, indicating the good chemical compatibility of La2-xBixCuO4 with SDC material. The bismuth doping significantly increased the electrical conductivity of the material. The highest conductivity reached 90.3 S·cm-1 at 350℃ for La1.9Bi0.1CuO4. The temperature programmed desorption (TPD) measurement proves that bismuth doping promotes the surface oxygen absorption ability of La2-xBixCuO4 material, and La1.9Bi0.1CuO4 shows the largest amount of oxygen vacancies among the Bi-doped materials. The electrochemical properties of La2-xBixCuO4 cathode materials were further studied by AC impedance spectroscopy under different oxygen partial pressures. The polarization resistance of La1.9Bi0.1CuO4 was 0.26 Ω·cm2 at 700℃ in air. The peak power density (PPD) at 700℃ was 308 mW·cm-2 for the SDC electrolyte supported single cell NiO-SDC/SDC/La1.90Bi0.10CuO4. The reaction rate limiting step is identified to be a mixed step involving the gas oxygen diffusion through the porous cathode and the surface adsorption process.
The cathode material La2-xBixCuO4 (x=0, 0.05, 0.10) for solid oxide fuel cell was synthesized by glycinenitrate method. The phase of the material was analyzed by X-ray diffraction (XRD) method. The results show that the material crystallizes in peroskite-type single phase oxide. Due to the increase doping amount of bismuth, the space group of the material changes from Fmmm to I4/mmm. The unit cell volume increases with the doping amount of bismuth. La2-xBixCuO4 cathode materials were found to show no chemical reaction with the electrolyte Sm0.2Ce0.8O1.9 (SDC) at 950℃ for 24 h, indicating the good chemical compatibility of La2-xBixCuO4 with SDC material. The bismuth doping significantly increased the electrical conductivity of the material. The highest conductivity reached 90.3 S·cm-1 at 350℃ for La1.9Bi0.1CuO4. The temperature programmed desorption (TPD) measurement proves that bismuth doping promotes the surface oxygen absorption ability of La2-xBixCuO4 material, and La1.9Bi0.1CuO4 shows the largest amount of oxygen vacancies among the Bi-doped materials. The electrochemical properties of La2-xBixCuO4 cathode materials were further studied by AC impedance spectroscopy under different oxygen partial pressures. The polarization resistance of La1.9Bi0.1CuO4 was 0.26 Ω·cm2 at 700℃ in air. The peak power density (PPD) at 700℃ was 308 mW·cm-2 for the SDC electrolyte supported single cell NiO-SDC/SDC/La1.90Bi0.10CuO4. The reaction rate limiting step is identified to be a mixed step involving the gas oxygen diffusion through the porous cathode and the surface adsorption process.
2021, 37(12): 2193-2202
doi: 10.11862/CJIC.2021.249
Abstract:
A three-dimensional metal-containing porous organic polymer (Fe2-POP) was synthesized using ferrous chloride, 2, 6-diformyl-4-methylphenol dioxime (H3DFMP) and tetra(4-(dihydroxy)borylphenyl)methane (TBPM) through one-step coordination and boric acid esterification dehydration polymerization reaction. Binuclear iron as the linear unit was formed by coordination between iron ion and H3DFMP, while TBPM was used as the tetrahedral linking unit, so that the three-dimensional porous organic polymer Fe2-POP with dia topology was produced. X-ray single crystal diffraction analysis of the model compound (MC-1) verified the structural characteristics of the dinuclear ferrous unit. Infrared spectroscopy and solid-state nuclear magnetism characterizations proved the formation of C=N and B-O in Fe2-POP. Fe2-POP had a high specific surface area of 510 m2·g-1 and uniform pore size (0.6-0.8 nm). X-ray photoelectron spectroscopy indicated the presence of divalent iron in Fe2-POP. Scanning electron microscopy and transmission electron microscopy showed that Fe2-POP was composed of 50-100 nm sphere-shaped particles. Electrochemical tests showed that Fe2-POP exhibited excellent electrochemical properties towards oxygen evolution reaction, and it only needed a small overpotential of 258 mV to deliver a current density of 10 mA·cm-2, and the Tafel slope was 71.0 mV·dec-1.
A three-dimensional metal-containing porous organic polymer (Fe2-POP) was synthesized using ferrous chloride, 2, 6-diformyl-4-methylphenol dioxime (H3DFMP) and tetra(4-(dihydroxy)borylphenyl)methane (TBPM) through one-step coordination and boric acid esterification dehydration polymerization reaction. Binuclear iron as the linear unit was formed by coordination between iron ion and H3DFMP, while TBPM was used as the tetrahedral linking unit, so that the three-dimensional porous organic polymer Fe2-POP with dia topology was produced. X-ray single crystal diffraction analysis of the model compound (MC-1) verified the structural characteristics of the dinuclear ferrous unit. Infrared spectroscopy and solid-state nuclear magnetism characterizations proved the formation of C=N and B-O in Fe2-POP. Fe2-POP had a high specific surface area of 510 m2·g-1 and uniform pore size (0.6-0.8 nm). X-ray photoelectron spectroscopy indicated the presence of divalent iron in Fe2-POP. Scanning electron microscopy and transmission electron microscopy showed that Fe2-POP was composed of 50-100 nm sphere-shaped particles. Electrochemical tests showed that Fe2-POP exhibited excellent electrochemical properties towards oxygen evolution reaction, and it only needed a small overpotential of 258 mV to deliver a current density of 10 mA·cm-2, and the Tafel slope was 71.0 mV·dec-1.
2021, 37(12): 2203-2208
doi: 10.11862/CJIC.2021.248
Abstract:
Cyclic discharge stability of lithium-sulfur batteries is relatively low. Herein, a method of low cost has been adopted to improve properties of lithium-sulfur batteries. A coating of acetylene black has been prepared on the surface of sulfur electrodes. The morphology of materials and properties for batteries have been tested. The results indicate that the sulfur adheres to the surface of acetylene black particles in sulfur-acetylene black composite with sulfur content (mass fraction) of 70%. The acetylene black coating with thickness of about 15 μm has been prepared on the surface of lithium electrodes. The voltage for oxidation reaction of sulfur electrodes with acetylene black coating was lower than that of sulfur electrodes. Acetylene black coating is helpful in oxidation reaction of sulfur electrodes. The aggregation degree of active materials for sulfur electrodes with acetylene black coating was lower than that for sulfur electrodes. The discharge specific capacity and cyclic discharge stability of sulfur electrodes with acetylene black coating were higher than those of sulfur electrodes. After 150 cycles of charge and discharge, the discharge specific capacity of sulfur electrodes with acetylene black coating was 894 mAh·g-1.
Cyclic discharge stability of lithium-sulfur batteries is relatively low. Herein, a method of low cost has been adopted to improve properties of lithium-sulfur batteries. A coating of acetylene black has been prepared on the surface of sulfur electrodes. The morphology of materials and properties for batteries have been tested. The results indicate that the sulfur adheres to the surface of acetylene black particles in sulfur-acetylene black composite with sulfur content (mass fraction) of 70%. The acetylene black coating with thickness of about 15 μm has been prepared on the surface of lithium electrodes. The voltage for oxidation reaction of sulfur electrodes with acetylene black coating was lower than that of sulfur electrodes. Acetylene black coating is helpful in oxidation reaction of sulfur electrodes. The aggregation degree of active materials for sulfur electrodes with acetylene black coating was lower than that for sulfur electrodes. The discharge specific capacity and cyclic discharge stability of sulfur electrodes with acetylene black coating were higher than those of sulfur electrodes. After 150 cycles of charge and discharge, the discharge specific capacity of sulfur electrodes with acetylene black coating was 894 mAh·g-1.
2021, 37(12): 2209-2218
doi: 10.11862/CJIC.2021.251
Abstract:
Under solvothermal conditions, two new UO22+ complexes[UO2(L1)(CH3COO)]·3CH3OH (C1) and[UO2 (L2)(Phen)(CH3O)] (C2) were synthesized by self-assembly with organic ligand containing N and O atom (L1=N', N‴-((2E, 3E)-butane-2, 3-diylidene)bis(4-hydroxybenzohydrazide), L2=2, 4, 5-trifluoro-3-methoxybenzoic acid, Phen=phenanthroline). The structure of the complexes was characterized by elemental analysis, infrared spectra and X-ray single crystal diffraction. The results show that the uranium ions in complexes C1 and C2 are all +6 valence. The uranium ions in complexes C1 and C2 adopt eight- and seven-coordinated modes, respectively. C1 forms a one-dimensional infinite chain structure through abundant O-H…O hydrogen bonds, and there are π-π stacking interactions in C2. The thermal stability and spectral properties of the complexes were studied, and the structures of the complexes were calculated theoretically. The dynamic stability of the complexes was discussed. CCDC: 2077418, C1; 2077419, C2.
Under solvothermal conditions, two new UO22+ complexes[UO2(L1)(CH3COO)]·3CH3OH (C1) and[UO2 (L2)(Phen)(CH3O)] (C2) were synthesized by self-assembly with organic ligand containing N and O atom (L1=N', N‴-((2E, 3E)-butane-2, 3-diylidene)bis(4-hydroxybenzohydrazide), L2=2, 4, 5-trifluoro-3-methoxybenzoic acid, Phen=phenanthroline). The structure of the complexes was characterized by elemental analysis, infrared spectra and X-ray single crystal diffraction. The results show that the uranium ions in complexes C1 and C2 are all +6 valence. The uranium ions in complexes C1 and C2 adopt eight- and seven-coordinated modes, respectively. C1 forms a one-dimensional infinite chain structure through abundant O-H…O hydrogen bonds, and there are π-π stacking interactions in C2. The thermal stability and spectral properties of the complexes were studied, and the structures of the complexes were calculated theoretically. The dynamic stability of the complexes was discussed. CCDC: 2077418, C1; 2077419, C2.
2021, 37(12): 2219-2226
doi: 10.11862/CJIC.2021.247
Abstract:
A bimetal oxide embedded biomass-derived carbon (MnWO4/BC) nanocomposite catalyst was synthesized using a co-precipitation approach, and it was used as a counter electrode (CE) catalyst to assemble a dye-sensitized solar cell (DSSC). The catalytic performance and photovoltaic performance of MnWO4/BC in non-iodine system was explored. To boost the photovoltaic performance of DSSC, a novel copper redox couple (Cu2+/Cu+) and dye (D35, Y123) were adopted for replacing the traditional I-/I3- redox couple and N719 dye, respectively. The resulting novel DSSC with MnWO4/BC nanocomposite CE catalyst had a photovoltage of approximately 0.89 V. Moreover, it exhibited power conversion efficiency (PCE) of 3.57% and 1.59% for D35 and Y123 dyes, respectively, which were 14.4% and 27.0%, respectively, higher than that in the case of Pt. Fifty continuous cyclic voltammetry tests show that MnWO4/BC catalyst has good electrochemical stability. It is observed that the catalytic activity of MnWO4/BC enhanced significantly due to the superior conductivity and the special pore structure of BC, the excellent electrocatalytic ability of MnWO4, and the synergistic effect between MnWO4 and BC.
A bimetal oxide embedded biomass-derived carbon (MnWO4/BC) nanocomposite catalyst was synthesized using a co-precipitation approach, and it was used as a counter electrode (CE) catalyst to assemble a dye-sensitized solar cell (DSSC). The catalytic performance and photovoltaic performance of MnWO4/BC in non-iodine system was explored. To boost the photovoltaic performance of DSSC, a novel copper redox couple (Cu2+/Cu+) and dye (D35, Y123) were adopted for replacing the traditional I-/I3- redox couple and N719 dye, respectively. The resulting novel DSSC with MnWO4/BC nanocomposite CE catalyst had a photovoltage of approximately 0.89 V. Moreover, it exhibited power conversion efficiency (PCE) of 3.57% and 1.59% for D35 and Y123 dyes, respectively, which were 14.4% and 27.0%, respectively, higher than that in the case of Pt. Fifty continuous cyclic voltammetry tests show that MnWO4/BC catalyst has good electrochemical stability. It is observed that the catalytic activity of MnWO4/BC enhanced significantly due to the superior conductivity and the special pore structure of BC, the excellent electrocatalytic ability of MnWO4, and the synergistic effect between MnWO4 and BC.
2021, 37(12): 2227-2234
doi: 10.11862/CJIC.2021.230
Abstract:
A cobalt-based MOF ([Co(4, 4'-bpy)(tfbdc)(H2O)2], Co-BTH, 4, 4'-bpy=4, 4'-bipyridune, H2tfbdc=tetrafluo-roterephthalic acid) was synthesized by a simple solvothermal reaction, and its performance as the electrode material for supercapacitors was evaluated for the first time. The results show that Co-BTH electrode has good pseudocapacitance performance, including high specific capacitance and good rate performance. In 1 mol·L-1 KOH solution, the maximum specific capacitance was 2 316 F·g-1 at a current density of 1 A·g-1. At the current density of 2 A·g-1, the specific capacity of the electrode still kept 847 F·g-1 after 1 000 cycles. The good pseudo-capacitance performance is related to the layered structure of Co-BTH and the small size nanosheets.
A cobalt-based MOF ([Co(4, 4'-bpy)(tfbdc)(H2O)2], Co-BTH, 4, 4'-bpy=4, 4'-bipyridune, H2tfbdc=tetrafluo-roterephthalic acid) was synthesized by a simple solvothermal reaction, and its performance as the electrode material for supercapacitors was evaluated for the first time. The results show that Co-BTH electrode has good pseudocapacitance performance, including high specific capacitance and good rate performance. In 1 mol·L-1 KOH solution, the maximum specific capacitance was 2 316 F·g-1 at a current density of 1 A·g-1. At the current density of 2 A·g-1, the specific capacity of the electrode still kept 847 F·g-1 after 1 000 cycles. The good pseudo-capacitance performance is related to the layered structure of Co-BTH and the small size nanosheets.
2021, 37(12): 2235-2243
doi: 10.11862/CJIC.2021.257
Abstract:
Using the amino group on the surface of g-C3N4 nanosheet, chemically cross-linked with the benzyl group chloride of the chloromethylated polyether sulfone (CMPES), which is the membrane substrate, then g-C3N4/CMPES composite membrane was provided by the phase inversion. The effects of the addition of g-C3N4 nanosheets on the structure, morphology, and filtration, photocatalysis, antifouling performance of composite membranes were systematically studied, meanwhile the mechanism of photocatalytic degradation of bovine serum albumin (BSA) solution was also discussed. The results showed that the photocatalytic performance and stability of the composite membrane were effectively improved by chemical bond between the g-C3N4 nanosheets and the membrane substrate material. Due to the photocatalytic effect and the hydrophilicity of g-C3N4 nanosheets, the composite membrane shows excellent filtration performance and anti-pollution performance.
Using the amino group on the surface of g-C3N4 nanosheet, chemically cross-linked with the benzyl group chloride of the chloromethylated polyether sulfone (CMPES), which is the membrane substrate, then g-C3N4/CMPES composite membrane was provided by the phase inversion. The effects of the addition of g-C3N4 nanosheets on the structure, morphology, and filtration, photocatalysis, antifouling performance of composite membranes were systematically studied, meanwhile the mechanism of photocatalytic degradation of bovine serum albumin (BSA) solution was also discussed. The results showed that the photocatalytic performance and stability of the composite membrane were effectively improved by chemical bond between the g-C3N4 nanosheets and the membrane substrate material. Due to the photocatalytic effect and the hydrophilicity of g-C3N4 nanosheets, the composite membrane shows excellent filtration performance and anti-pollution performance.
2021, 37(12): 2244-2248
doi: 10.11862/CJIC.2021.259
Abstract:
We synthesized a new type of ClO- fluorescence probe using 2, 7-dibromo-9-fluorenone as raw material by two-step conventional reaction. In phosphate buffered saline (PBS), with the increase of ClO-, the emission of the probe at 511 nm gradually enhanced, presenting green fluorescence emission. The probe reacted with ClO- quickly and the reaction was completed within 10 s. In addition, the present method exhibited high sensitivity to ClO- with a limit of detection of 0.74 μmol·L-1. Cell image experiments showed that the probe could detect endogenous and exogenous ClO- at the cellular level.
We synthesized a new type of ClO- fluorescence probe using 2, 7-dibromo-9-fluorenone as raw material by two-step conventional reaction. In phosphate buffered saline (PBS), with the increase of ClO-, the emission of the probe at 511 nm gradually enhanced, presenting green fluorescence emission. The probe reacted with ClO- quickly and the reaction was completed within 10 s. In addition, the present method exhibited high sensitivity to ClO- with a limit of detection of 0.74 μmol·L-1. Cell image experiments showed that the probe could detect endogenous and exogenous ClO- at the cellular level.
2021, 37(12): 2249-2259
doi: 10.11862/CJIC.2021.256
Abstract:
Based on an etching strategy of treating a Cu-organic framework with tannic acid, a loose and porous CuO (denoted as E-CuO) was obtained. E-CuO modified glassy carbon electrode (E-CuO/GCE) was applied in the electrochemical sensing of glucose. E-CuO/GCE showed a high sensitivity of 0.273 μA·μL·mol-1·cm-2 in the glucose concentration range of 0.25-2 000 μmol·L-1, as well as good anti-interference performance, repeatability and stability. In the analysis of practical samples, E-CuO/GCE performed well in the experiment of spiked recoveries of honey and fruit sugar, and E-CuO/GCE could be used in glucose detection in glucose injection.
Based on an etching strategy of treating a Cu-organic framework with tannic acid, a loose and porous CuO (denoted as E-CuO) was obtained. E-CuO modified glassy carbon electrode (E-CuO/GCE) was applied in the electrochemical sensing of glucose. E-CuO/GCE showed a high sensitivity of 0.273 μA·μL·mol-1·cm-2 in the glucose concentration range of 0.25-2 000 μmol·L-1, as well as good anti-interference performance, repeatability and stability. In the analysis of practical samples, E-CuO/GCE performed well in the experiment of spiked recoveries of honey and fruit sugar, and E-CuO/GCE could be used in glucose detection in glucose injection.
2021, 37(12): 2260-2266
doi: 10.11862/CJIC.2021.227
Abstract:
Here, platinum nanoparticles were synthesized on multi-walled carbon nanotubes (MWCNTs) in one step under the irradiation of visible light without any extra additives except ethylene glycol (EG) as the reducing agent and stabilizer, and Pt/MWCNTs composites were successfully prepared. The catalytic performance of Pt/MWCNTs was studied in the reduction of p-nitrophenol (p-NP). The morphology and crystal structure of as-synthesized materials were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Visible light irradiation promotes the hydrolysis of a[PtCl4]2- precursor in EG aqueous solution. By the electronic effect of the metal interface, the reduction of platinum precursors makes the formation of the uniformly dispersed Pt metal ultra-small particles with an average of 2.1 nm size. The as-prepared Pt/MWCNTs effectively catalyzed the reduction of p-NP to p-aminophenol (p-AP) with NaBH4, exhibiting a high catalytic performance with an apparent rate constant of 0.25 min-1. Furthermore, high reusability without significant activity loss presents that Pt/MWCNTs prepared can be an excellent and stable catalyst. The experimental results prove that besides traditional light irradiation methods, e.g. ultraviolet, the proper utilization of visible light is also a very effective method for preparing platinum metal catalysts and the morphology control can be achieved in some simple ways rather than complex reaction conditions.
Here, platinum nanoparticles were synthesized on multi-walled carbon nanotubes (MWCNTs) in one step under the irradiation of visible light without any extra additives except ethylene glycol (EG) as the reducing agent and stabilizer, and Pt/MWCNTs composites were successfully prepared. The catalytic performance of Pt/MWCNTs was studied in the reduction of p-nitrophenol (p-NP). The morphology and crystal structure of as-synthesized materials were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Visible light irradiation promotes the hydrolysis of a[PtCl4]2- precursor in EG aqueous solution. By the electronic effect of the metal interface, the reduction of platinum precursors makes the formation of the uniformly dispersed Pt metal ultra-small particles with an average of 2.1 nm size. The as-prepared Pt/MWCNTs effectively catalyzed the reduction of p-NP to p-aminophenol (p-AP) with NaBH4, exhibiting a high catalytic performance with an apparent rate constant of 0.25 min-1. Furthermore, high reusability without significant activity loss presents that Pt/MWCNTs prepared can be an excellent and stable catalyst. The experimental results prove that besides traditional light irradiation methods, e.g. ultraviolet, the proper utilization of visible light is also a very effective method for preparing platinum metal catalysts and the morphology control can be achieved in some simple ways rather than complex reaction conditions.
2021, 37(12): 2267-2278
doi: 10.11862/CJIC.2021.244
Abstract:
Two copper binuclear complexes[Cu(tpyc)(H2btc)]2 (1), [Cu2(tpyc)2(suc)(H2O)2] (2) and one coordination polymer {[Cu3(tpyc)3(OH)2(H2O)2]ClO4}n (3) (H3btc=1, 3, 5-benzenetricarboxylic acid, H2suc=succinic acid, Htpyc=2, 2': 6'2″-terpyridine-4'-carboxylic acid) have been synthesized under solvothermal conditions and characterized by elemental analysis, FT-IR spectroscopy, single-crystal X-ray diffraction, powder X-ray diffraction, thermogravimetric analysis and magnetic analysis. Structural analysis suggests that complexes 1-3 display 3D supramolecular networks by multiple hydrogen-bonding interactions. Magnetic studies show that ferromagnetic coupling exists between Cu(Ⅱ) ions in complex 1, while antiferromagnetic interaction exists between Cu(Ⅱ) ions in complex 2.
Two copper binuclear complexes[Cu(tpyc)(H2btc)]2 (1), [Cu2(tpyc)2(suc)(H2O)2] (2) and one coordination polymer {[Cu3(tpyc)3(OH)2(H2O)2]ClO4}n (3) (H3btc=1, 3, 5-benzenetricarboxylic acid, H2suc=succinic acid, Htpyc=2, 2': 6'2″-terpyridine-4'-carboxylic acid) have been synthesized under solvothermal conditions and characterized by elemental analysis, FT-IR spectroscopy, single-crystal X-ray diffraction, powder X-ray diffraction, thermogravimetric analysis and magnetic analysis. Structural analysis suggests that complexes 1-3 display 3D supramolecular networks by multiple hydrogen-bonding interactions. Magnetic studies show that ferromagnetic coupling exists between Cu(Ⅱ) ions in complex 1, while antiferromagnetic interaction exists between Cu(Ⅱ) ions in complex 2.
2021, 37(12): 2279-2288
doi: 10.11862/CJIC.2021.253
Abstract:
Two coordination compounds[Ni(DBTA)(DMF)(H2O)4] (1) and[Co(DBTA)(DMF)(H2O)4] (2) (D-H2DBTA=(+)-2, 3-dibenzoyl-D-tartaric acid, DMF=N, N-dimethylformamide) have been synthesized at room temperature, and characterized by elemental analyses (EA), FT-IR, X-ray single-crystal and powder diffraction analyses. The structural analysis shows that complexes 1 and 2 are isomorphic. They belong to the monoclinic system with P21 space group and display a zero-dimensional structure constructed from coordination bonds, which is further interlinked to form a three-dimensional network via hydrogen-bonding interactions. Fluorescence measurements indicate that 1 and 2 can exhibit strong fluorescence using 280 nm as the excitation wavelength. Though 1 and 2 are isomorphic, they displayed different magnetic properties. Complex 1 dominates weak antiferromagnetic couplings between Ni2+ cations, while complex 2 exhibits the magnetic anisotropy of the Co2+ center and antiferromagnetic interactions between the Co2+ cations.
Two coordination compounds[Ni(DBTA)(DMF)(H2O)4] (1) and[Co(DBTA)(DMF)(H2O)4] (2) (D-H2DBTA=(+)-2, 3-dibenzoyl-D-tartaric acid, DMF=N, N-dimethylformamide) have been synthesized at room temperature, and characterized by elemental analyses (EA), FT-IR, X-ray single-crystal and powder diffraction analyses. The structural analysis shows that complexes 1 and 2 are isomorphic. They belong to the monoclinic system with P21 space group and display a zero-dimensional structure constructed from coordination bonds, which is further interlinked to form a three-dimensional network via hydrogen-bonding interactions. Fluorescence measurements indicate that 1 and 2 can exhibit strong fluorescence using 280 nm as the excitation wavelength. Though 1 and 2 are isomorphic, they displayed different magnetic properties. Complex 1 dominates weak antiferromagnetic couplings between Ni2+ cations, while complex 2 exhibits the magnetic anisotropy of the Co2+ center and antiferromagnetic interactions between the Co2+ cations.
2021, 37(12): 2289-2297
doi: 10.11862/CJIC.2021.240
Abstract:
Quasi-metal-organic-frameworks (MOFs) derivative-based MFe-T (T℃ stands for calcination temperature) photocatalysts with a porous structure were synthesized by the pyrolysis of MIL-53(Fe) (termed MFe hereafter). Among the tested catalysts, MFe-250 exhibited the highest photodegradation performance, degradation of 99% methylene blue (MB) within 90 min. From the photocurrent and electrochemical impedance spectroscopy results, the electronic transmission capability of MFe-250 exceeded that of MFe. Furthermore, trapping experiments revealed that while hydroxyl radicals (·OH) were essential intermediates in the photocatalytic degradation of MB. Additionally, a mechanism for the photocatalytic process was proposed.
Quasi-metal-organic-frameworks (MOFs) derivative-based MFe-T (T℃ stands for calcination temperature) photocatalysts with a porous structure were synthesized by the pyrolysis of MIL-53(Fe) (termed MFe hereafter). Among the tested catalysts, MFe-250 exhibited the highest photodegradation performance, degradation of 99% methylene blue (MB) within 90 min. From the photocurrent and electrochemical impedance spectroscopy results, the electronic transmission capability of MFe-250 exceeded that of MFe. Furthermore, trapping experiments revealed that while hydroxyl radicals (·OH) were essential intermediates in the photocatalytic degradation of MB. Additionally, a mechanism for the photocatalytic process was proposed.
