Login In
2018 Volume 35 Issue 4
2018, 35(4): 369-380
doi: 10.11944/j.issn.1000-0518.2018.04.170382
Abstract:
Metal oxide@MOF(metal-organic framework) composite materials have emerged as a new class of functional materials and attracted considerable interests in many fields due to the unique properties in combination of metal oxide with MOF, which has been an important research direction of MOF materials in recent years. In this review, we systematically summarize the research progress towards various synthetic methods for metal oxide@MOF composite materials, such as epitaxial growth method, gas phase infiltration method and template method. The advantages and disadvantages of these methods are discussed, respectively. Applications of metal oxide@MOFs composite materials in adsorption and separation, catalysis, sensing, biomedical and potential applications of metal oxide@MOFs composite materials in electrochemical research are also discussed. In order to expand its application in industry, the improvement of synthetic methods, the preparation of new functional metal oxides and the exploration of new structures are proposed as the main future research and development directions of metal oxide@MOFs composite materials.
Metal oxide@MOF(metal-organic framework) composite materials have emerged as a new class of functional materials and attracted considerable interests in many fields due to the unique properties in combination of metal oxide with MOF, which has been an important research direction of MOF materials in recent years. In this review, we systematically summarize the research progress towards various synthetic methods for metal oxide@MOF composite materials, such as epitaxial growth method, gas phase infiltration method and template method. The advantages and disadvantages of these methods are discussed, respectively. Applications of metal oxide@MOFs composite materials in adsorption and separation, catalysis, sensing, biomedical and potential applications of metal oxide@MOFs composite materials in electrochemical research are also discussed. In order to expand its application in industry, the improvement of synthetic methods, the preparation of new functional metal oxides and the exploration of new structures are proposed as the main future research and development directions of metal oxide@MOFs composite materials.
2018, 35(4): 381-393
doi: 10.11944/j.issn.1000-0518.2018.04.170212
Abstract:
It is a high efficient method to prepare Mg-RE(rare earth) alloys in molten salt electrochemical process for its easy mass production and simple procedure. The RE element distributes uniformly and continuously in prepared Mg alloys. The heavy and light RE elements are extracted by electrolyzing from fluoride fusion and chloride fusion, respectively. Recent advances in preparation of Mg-RE alloys in molten salt electrochemical process are elaborately discussed from materials, electrolytic tank, electrode process, technical parameters and anodic gas absorption, and some beneficial advices focused on future developments about preparation of Mg-RE alloy are indicated.
It is a high efficient method to prepare Mg-RE(rare earth) alloys in molten salt electrochemical process for its easy mass production and simple procedure. The RE element distributes uniformly and continuously in prepared Mg alloys. The heavy and light RE elements are extracted by electrolyzing from fluoride fusion and chloride fusion, respectively. Recent advances in preparation of Mg-RE alloys in molten salt electrochemical process are elaborately discussed from materials, electrolytic tank, electrode process, technical parameters and anodic gas absorption, and some beneficial advices focused on future developments about preparation of Mg-RE alloy are indicated.
2018, 35(4): 394-400
doi: 10.11944/j.issn.1000-0518.2018.04.170151
Abstract:
The sulfur-iodine(S-I) thermochemical water-splitting cycle is one of the high-efficient methods for hydrogen production, which can be carried out at relatively low temperatures. The Bunsen reaction is particularly important as the core step of the cycle. In order to facilitate the effective separation of Bunsen reaction products, i.e., sulfuric acid and hydroiodic acid, new methods for carrying out Bunsen reaction have been studied by many scholars. In this paper, two new Bunsen reaction routes, including Bunsen reaction in non-aqueous solvents and electrochemical Bunsen reaction were reviewed. The separation of reaction products in non-aqueous solvents was discussed.The properties, advantages and disadvantages of various non-aqueous solvents were compared. It is found that the solvents adopted at present have met the requirements for the separation of Bunsen reaction products, and can be used for the Bunsen reaction, but the recovery and reuse of the solvents are difficult. The research status of electrochemical Bunsen reaction, and the comparison between the progress of two typical research teams were also summarized in this work. Most efforts have been made on the fundamental characteristics of the reaction, further attention can be paid to the electrochemical Bunsen reaction mechanism, cell structure design and optimization, and even construction of novel S-I cycle system.
The sulfur-iodine(S-I) thermochemical water-splitting cycle is one of the high-efficient methods for hydrogen production, which can be carried out at relatively low temperatures. The Bunsen reaction is particularly important as the core step of the cycle. In order to facilitate the effective separation of Bunsen reaction products, i.e., sulfuric acid and hydroiodic acid, new methods for carrying out Bunsen reaction have been studied by many scholars. In this paper, two new Bunsen reaction routes, including Bunsen reaction in non-aqueous solvents and electrochemical Bunsen reaction were reviewed. The separation of reaction products in non-aqueous solvents was discussed.The properties, advantages and disadvantages of various non-aqueous solvents were compared. It is found that the solvents adopted at present have met the requirements for the separation of Bunsen reaction products, and can be used for the Bunsen reaction, but the recovery and reuse of the solvents are difficult. The research status of electrochemical Bunsen reaction, and the comparison between the progress of two typical research teams were also summarized in this work. Most efforts have been made on the fundamental characteristics of the reaction, further attention can be paid to the electrochemical Bunsen reaction mechanism, cell structure design and optimization, and even construction of novel S-I cycle system.
2018, 35(4): 401-409
doi: 10.11944/j.issn.1000-0518.2018.04.170463
Abstract:
A pH and thermo-responsive fluorescent polymeric sensor Poly(POSS-NI-NIPAM) was synthesized from naphthalimide(NI), N-isopropyl acrylamide(NIPAM) and polyhedral oligomeric silsesquioxane(POSS) as raw materials by the reversible addition-fragmentation chain transfer polymerization(RAFT). The pH and thermo-responsive properties of Poly(POSS-NI-NIPAM) were characterized by nuclear magnetic resonance spectroscopy(NMR), fluorescence emission spectrometer and mass spectrometry(MS). The results show that Poly(POSS-NI-NIPAM) shows obvious fluorescence changes in the range of pH 5.8~8.0 with a reversible performance. The high sensitivity for pH/temperature makes Poly(POSS-NI-NIPAM) as a promising fluorescent probe for the detection of intracellular pH/temperature in living cells.
A pH and thermo-responsive fluorescent polymeric sensor Poly(POSS-NI-NIPAM) was synthesized from naphthalimide(NI), N-isopropyl acrylamide(NIPAM) and polyhedral oligomeric silsesquioxane(POSS) as raw materials by the reversible addition-fragmentation chain transfer polymerization(RAFT). The pH and thermo-responsive properties of Poly(POSS-NI-NIPAM) were characterized by nuclear magnetic resonance spectroscopy(NMR), fluorescence emission spectrometer and mass spectrometry(MS). The results show that Poly(POSS-NI-NIPAM) shows obvious fluorescence changes in the range of pH 5.8~8.0 with a reversible performance. The high sensitivity for pH/temperature makes Poly(POSS-NI-NIPAM) as a promising fluorescent probe for the detection of intracellular pH/temperature in living cells.
2018, 35(4): 410-419
doi: 10.11944/j.issn.1000-0518.2018.04.170098
Abstract:
Hypoxia-inducible factor 1(HIF-1) is closely related to the growth, invasion and drug resistance of tumor cells and is highly expressed in tumor cells, so new HIF-1 inhibitors can be used as potential antitumor drugs. Nine 1, 3-substituted indazole derivatives were synthesized. The expression of HIF-1 and its target gene vascular endothelial growth factor(VEGF) were detected by Western Blot and Real time-PCR(polymerase chain reaction), and the anti-tumor activities of all the newly synthesized compounds were evaluated on the in vitro growth of HepG2 cell line taking 3-(5'-hydroxymethyl-2'-furyl)-1-benzyl indazole(YC-1)(compound 7d) as positive control. We found that compound 7b significantly inhibited the expression of HIF-1 and its downstream target gene VEGF, and the anti-hepatoma biological activity in vitro of compound 7b was better than that of YC-1 with half maximal inhibitory concentration(IC50) values of 10.37 μmol/L. The results show that 3-(5'-hydroxy methyl-2'-furan)-1-(1' -p-tolylsulfonyl) indazole targets the inhibition of HIF activity, but also has a good anti-hepatoma activity.
Hypoxia-inducible factor 1(HIF-1) is closely related to the growth, invasion and drug resistance of tumor cells and is highly expressed in tumor cells, so new HIF-1 inhibitors can be used as potential antitumor drugs. Nine 1, 3-substituted indazole derivatives were synthesized. The expression of HIF-1 and its target gene vascular endothelial growth factor(VEGF) were detected by Western Blot and Real time-PCR(polymerase chain reaction), and the anti-tumor activities of all the newly synthesized compounds were evaluated on the in vitro growth of HepG2 cell line taking 3-(5'-hydroxymethyl-2'-furyl)-1-benzyl indazole(YC-1)(compound 7d) as positive control. We found that compound 7b significantly inhibited the expression of HIF-1 and its downstream target gene VEGF, and the anti-hepatoma biological activity in vitro of compound 7b was better than that of YC-1 with half maximal inhibitory concentration(IC50) values of 10.37 μmol/L. The results show that 3-(5'-hydroxy methyl-2'-furan)-1-(1' -p-tolylsulfonyl) indazole targets the inhibition of HIF activity, but also has a good anti-hepatoma activity.
2018, 35(4): 420-425
doi: 10.11944/j.issn.1000-0518.2018.04.170147
Abstract:
Three aniline p-adamantanylcinnamides(8a~8c) were designed and synthesized from cross coupling of 1-bromoadamantane with toluene followed by oxidation, homologation and amidation. The inhibitory assays of these compounds against human hepatocellular carcinoma cell SMMC7721, breast cancer cell MCF-7, cervical cancer cell Hela and lung cancer cell A549 by MTS method showed that compound 8c exhibited good antitumor activity against human hepatoma cells(IC50=1.6 μmol/L or 0.73 mg/L) compared with doxorubicin(0.44 mg/L). This indicates that aniline p-adamantanylcinnamide is a good template for the development of anti-tumor drugs. The antitumor activity, cellular targets and the mode of action of aniline p-adamantanylcinnamide derivatives will be further studied.
Three aniline p-adamantanylcinnamides(8a~8c) were designed and synthesized from cross coupling of 1-bromoadamantane with toluene followed by oxidation, homologation and amidation. The inhibitory assays of these compounds against human hepatocellular carcinoma cell SMMC7721, breast cancer cell MCF-7, cervical cancer cell Hela and lung cancer cell A549 by MTS method showed that compound 8c exhibited good antitumor activity against human hepatoma cells(IC50=1.6 μmol/L or 0.73 mg/L) compared with doxorubicin(0.44 mg/L). This indicates that aniline p-adamantanylcinnamide is a good template for the development of anti-tumor drugs. The antitumor activity, cellular targets and the mode of action of aniline p-adamantanylcinnamide derivatives will be further studied.
2018, 35(4): 426-435
doi: 10.11944/j.issn.1000-0518.2018.04.170206
Abstract:
A novel asymmetrical linear conjugated diacetylene derivative, (2-(2-(4-aminophenyl)ethynyl)-5-(4-(2-(hexyloxy)naphthalen-6-yl)buta-1, 3-diynyl)phenyl)methanol, was designed and synthesized from phenylamine and arylacetylene by Sonogashira reaction. By attaching the phenylamino substituent to arylacetylene, torsional states will be formed under conditions of the absence of electron withdrawing group and an effective intramolecular charge-transfer occurs, which helps improve electro-optical conversion efficiency. Furthermore, the introduction of liquid crystal property improves the charge balance of electron and hole in device and device efficiency. Moreover, an organic light-emitting device(OLED) device using the compound as emitters was fabricated, which exhibited yellow-green emission and low turn-on voltages of 7.2 V and excellent electroluminescent stability. The maximum brightness value was 126 cd/m2. So, the diacetylene derivative is a promising materials for OLED devices.
A novel asymmetrical linear conjugated diacetylene derivative, (2-(2-(4-aminophenyl)ethynyl)-5-(4-(2-(hexyloxy)naphthalen-6-yl)buta-1, 3-diynyl)phenyl)methanol, was designed and synthesized from phenylamine and arylacetylene by Sonogashira reaction. By attaching the phenylamino substituent to arylacetylene, torsional states will be formed under conditions of the absence of electron withdrawing group and an effective intramolecular charge-transfer occurs, which helps improve electro-optical conversion efficiency. Furthermore, the introduction of liquid crystal property improves the charge balance of electron and hole in device and device efficiency. Moreover, an organic light-emitting device(OLED) device using the compound as emitters was fabricated, which exhibited yellow-green emission and low turn-on voltages of 7.2 V and excellent electroluminescent stability. The maximum brightness value was 126 cd/m2. So, the diacetylene derivative is a promising materials for OLED devices.
2018, 35(4): 436-441
doi: 10.11944/j.issn.1000-0518.2018.04.170130
Abstract:
In this paper, the inhibitory effects of five Dawson type phosphomolybdic acids, e.g., H7[P2Mo17VO62], H8[P2Mo16V2O62], H9[P2Mo15V3O62], H8[P2Mo14V4O62H2] and H9[P2Mo13V5O62H2](abbreviated to P2Mo17V, P2Mo16V2, P2Mo15V3, P2Mo14V4 and P2Mo13V5, respectively), on the diphenolase activity of mushroom tyrosinase were investigated by enzyme kinetics methods. The results show that P2Mo17V, P2Mo16V2 and P2Mo15V3 have significant inhibitory effects on tyrosinase, and the half maximal inhibitory concentration(IC50) values of them are 0.409, 0.386 and 0.386 mmol/L, respectively. They are reversible and competitive inhibitors, and the inhibition constants are 0.234, 0.391 and 0.249 mmol/L, respectively. P2Mo13V5 can activate diphenolase activity of tyrosinase while P2Mo14V4 in 0~1.0 mmol/L has no obvious effects on the diphenolase activity of tyrosinase.
In this paper, the inhibitory effects of five Dawson type phosphomolybdic acids, e.g., H7[P2Mo17VO62], H8[P2Mo16V2O62], H9[P2Mo15V3O62], H8[P2Mo14V4O62H2] and H9[P2Mo13V5O62H2](abbreviated to P2Mo17V, P2Mo16V2, P2Mo15V3, P2Mo14V4 and P2Mo13V5, respectively), on the diphenolase activity of mushroom tyrosinase were investigated by enzyme kinetics methods. The results show that P2Mo17V, P2Mo16V2 and P2Mo15V3 have significant inhibitory effects on tyrosinase, and the half maximal inhibitory concentration(IC50) values of them are 0.409, 0.386 and 0.386 mmol/L, respectively. They are reversible and competitive inhibitors, and the inhibition constants are 0.234, 0.391 and 0.249 mmol/L, respectively. P2Mo13V5 can activate diphenolase activity of tyrosinase while P2Mo14V4 in 0~1.0 mmol/L has no obvious effects on the diphenolase activity of tyrosinase.
2018, 35(4): 442-448
doi: 10.11944/j.issn.1000-0518.2018.04.170086
Abstract:
[Zn2(oba)2·2H2O]n was synthesized from 2, 2'-biphenyl carboxylic acid(H2oba) and Zn(Ⅱ) by the hydrothermal method. Its structure was characterized by X-ray diffraction analysis, elemental analysis, fluorescence analysis and thermo gravimetric analysis. The results show that the compound is monoclinic, space group P21/c and the unit cell of the compound contains two separate zinc ions, two H2oba ligands and two water molecules. The compound has a one-dimensional chain structure with infinite circulation under the action of the coordination bond. The linking of one-dimensional chain structure by hydrogen bonds forms its two-dimensional chain structure. In addition, the antioxidant activity studies show that the compound has good antioxidant activity with an IC50(Half inhibitory concentration) value of 25 mg/L and is a good mimic of superoxide dismutase(SOD).
[Zn2(oba)2·2H2O]n was synthesized from 2, 2'-biphenyl carboxylic acid(H2oba) and Zn(Ⅱ) by the hydrothermal method. Its structure was characterized by X-ray diffraction analysis, elemental analysis, fluorescence analysis and thermo gravimetric analysis. The results show that the compound is monoclinic, space group P21/c and the unit cell of the compound contains two separate zinc ions, two H2oba ligands and two water molecules. The compound has a one-dimensional chain structure with infinite circulation under the action of the coordination bond. The linking of one-dimensional chain structure by hydrogen bonds forms its two-dimensional chain structure. In addition, the antioxidant activity studies show that the compound has good antioxidant activity with an IC50(Half inhibitory concentration) value of 25 mg/L and is a good mimic of superoxide dismutase(SOD).
2018, 35(4): 449-456
doi: 10.11944/j.issn.1000-0518.2018.04.170108
Abstract:
Carboxylate-based task-specific ionic liquids(ILs), viz., 1, 3-dimethylimidazolium acetate([C1mim] [CH3COO]) and 1, 3-dimethylimidazolium hydroxylcarboxylate([C1mim] [HOCH2COO]), have been synthesized, and used as the solvents for cellulose dissolution. The results show that the structure of anions has a significant influence on cellulose dissolution; and at 120℃, the solubility of cellulose in[C1mim] [CH3COO] and[C1mim] [HOCH2COO] can reach up to 19.7% and 21.2%, respectively. The structure and thermal stability of pristine and regenerated celluloses were characterized by Fourier transform infrared spectroscopy(FT-IR), X-ray diffraction(XRD), and thermogravimetry analysis(TGA) methods. These results demonstrate that the two ionic liquids are the direct solvent for cellulose, and also indicate that the transformation from cellulose I to amorphous cellulose occurrs after the dissolution and regeneration processes in ionic liquids. Moreover, further analysis on the degree of polymerization(DP) of regenerated cellulose shows that the dissolution temperature and time have the negative effect on cellulose DP; and higher dissolution temperature or longer dissolution time affords the lower DP of regenerated cellulose. These results may serve as guidance for developing new cellulose solvent systems in the future.
Carboxylate-based task-specific ionic liquids(ILs), viz., 1, 3-dimethylimidazolium acetate([C1mim] [CH3COO]) and 1, 3-dimethylimidazolium hydroxylcarboxylate([C1mim] [HOCH2COO]), have been synthesized, and used as the solvents for cellulose dissolution. The results show that the structure of anions has a significant influence on cellulose dissolution; and at 120℃, the solubility of cellulose in[C1mim] [CH3COO] and[C1mim] [HOCH2COO] can reach up to 19.7% and 21.2%, respectively. The structure and thermal stability of pristine and regenerated celluloses were characterized by Fourier transform infrared spectroscopy(FT-IR), X-ray diffraction(XRD), and thermogravimetry analysis(TGA) methods. These results demonstrate that the two ionic liquids are the direct solvent for cellulose, and also indicate that the transformation from cellulose I to amorphous cellulose occurrs after the dissolution and regeneration processes in ionic liquids. Moreover, further analysis on the degree of polymerization(DP) of regenerated cellulose shows that the dissolution temperature and time have the negative effect on cellulose DP; and higher dissolution temperature or longer dissolution time affords the lower DP of regenerated cellulose. These results may serve as guidance for developing new cellulose solvent systems in the future.
2018, 35(4): 457-461
doi: 10.11944/j.issn.1000-0518.2018.04.170415
Abstract:
The impurity elements in lutetium oxide have a great influence on the separation and preparation process, production cost and performance of lutetium based silicate scintillating crystals. The research about the effect of impurities on the crystal properties is limited and needs to be further improved. In this paper, the impurity elements(Yb3+ and Ca2+ are the key impure elements in Lu2O3 separation process) co-doped Lu2SiO5:Ce polycrystalline powders were prepared by the solid-state method. The effects of Yb3+ or Ca2+ content on the spectral properties of polycrystalline powders were studied. The results show that co-doping of Yb3+ or Ca2+ does not change the shape and position of the emission spectra. With the increase of the amount of doping impurities, the spectral intensity and fluorescence lifetime decrease gradually.
The impurity elements in lutetium oxide have a great influence on the separation and preparation process, production cost and performance of lutetium based silicate scintillating crystals. The research about the effect of impurities on the crystal properties is limited and needs to be further improved. In this paper, the impurity elements(Yb3+ and Ca2+ are the key impure elements in Lu2O3 separation process) co-doped Lu2SiO5:Ce polycrystalline powders were prepared by the solid-state method. The effects of Yb3+ or Ca2+ content on the spectral properties of polycrystalline powders were studied. The results show that co-doping of Yb3+ or Ca2+ does not change the shape and position of the emission spectra. With the increase of the amount of doping impurities, the spectral intensity and fluorescence lifetime decrease gradually.
2018, 35(4): 462-468
doi: 10.11944/j.issn.1000-0518.2018.04.170102
Abstract:
A shaped activated carbon(AC) prepared after carbonization and physical activation, starting from pitch and elutrilithe, was further hydrothermally treated with alkaline solution. The effect of crystallization time on the formation of zeolite 4A, the pore structure and the adsorption ability of the composite towards CH4 and N2 were investigated by X-ray diffraction(XRD), scanning electron microscopy(SEM), N2 adsorption-desorption at 77 K and CO2 adsorption isotherm at 273 K. The results show that silicon and aluminum in this composite are converted to zeolite 4A during the hydrothermal treatment. Simultaneously, micropores between 0.45~0.6 nm are appeared, the micropore volume is increased, accompanied by the presence of a few mesopores and macropores. Adsorption isotherms at 298 K indicate that the adsorption amount of CH4 by composite AC-2(crystalized for 6 hours) is elevated to 10.8 mL/g with a high CH4/N2 equilibrium selectivity of 3.7.
A shaped activated carbon(AC) prepared after carbonization and physical activation, starting from pitch and elutrilithe, was further hydrothermally treated with alkaline solution. The effect of crystallization time on the formation of zeolite 4A, the pore structure and the adsorption ability of the composite towards CH4 and N2 were investigated by X-ray diffraction(XRD), scanning electron microscopy(SEM), N2 adsorption-desorption at 77 K and CO2 adsorption isotherm at 273 K. The results show that silicon and aluminum in this composite are converted to zeolite 4A during the hydrothermal treatment. Simultaneously, micropores between 0.45~0.6 nm are appeared, the micropore volume is increased, accompanied by the presence of a few mesopores and macropores. Adsorption isotherms at 298 K indicate that the adsorption amount of CH4 by composite AC-2(crystalized for 6 hours) is elevated to 10.8 mL/g with a high CH4/N2 equilibrium selectivity of 3.7.
2018, 35(4): 469-476
doi: 10.11944/j.issn.1000-0518.2018.04.170111
Abstract:
Cu2O micro-and nanoparticles with different morphologies(cube, microsphere, hollow sphere and core-shell) were prepared by polyol method, using copper nitrate, copper acetate, and copper acetylacetonate as raw materials. The samples were characterized by X-ray diffraction(XRD), field emission scanning electron microscopy(FE-SEM), transmission electron microscopy(TEM), high resolution TEM(HRTEM) and ultraviolet-visible(UV-Vis) spectroscopy. We investigated the influences of copper sources, reaction time, the polyol types and other conditions on the morphology of cuprous oxide. The mechanism for the formation of Cu2O in polyol process is discussed. Synthesis of cuprous oxide micro-and nanostructures with different shape can be controlled by the simple and inexpensive polyol method. This method is promising for the preparation of oxides with controlled morphologies.
Cu2O micro-and nanoparticles with different morphologies(cube, microsphere, hollow sphere and core-shell) were prepared by polyol method, using copper nitrate, copper acetate, and copper acetylacetonate as raw materials. The samples were characterized by X-ray diffraction(XRD), field emission scanning electron microscopy(FE-SEM), transmission electron microscopy(TEM), high resolution TEM(HRTEM) and ultraviolet-visible(UV-Vis) spectroscopy. We investigated the influences of copper sources, reaction time, the polyol types and other conditions on the morphology of cuprous oxide. The mechanism for the formation of Cu2O in polyol process is discussed. Synthesis of cuprous oxide micro-and nanostructures with different shape can be controlled by the simple and inexpensive polyol method. This method is promising for the preparation of oxides with controlled morphologies.
Preparation and Electrochemical Performance of Nitrogen Doped Carbon Materials Based on Polydopamine
2018, 35(4): 477-483
doi: 10.11944/j.issn.1000-0518.2018.04.170094
Abstract:
Porous carbon materials have been extensively studied in the field of electrode materials for supercapacitor due to their high surface area, excellent electron conductivity and good chemical stability. The composition and pore structure of carbon materials directly affect their electrochemical performance. In order to further improve their capacitance performance, nitrogen doped carbon materials with excellent electrochemical performance were prepared for the first time by high temperature carbonization with polydopamine as precursor and KOH as activator. The surface morphology, structure and composition of the obtained N-doped porous carbon materials were characterized by scanning electron microscopy(SEM), transmission electron microscopy(TEM), X-ray diffraction spectra(XRD), Fourier transform infrared spectrometer(FT-IR), X-ray photoelectron spectroscopy(XPS) and Raman spectroscopy, respectively. The electrochemical performances were investigated by cyclic voltammetry and galvanostatic charge/discharge in 6 mol/L KOH electrolyte. The results show that the specific capacitance of the material can reach 269 F/g at the current density of 1 A/g due to the synergistic effect of double layer capacitance and pseudocapacitance, and the capacitance still remains 93.5% after 1000 charge-discharge cycles.
Porous carbon materials have been extensively studied in the field of electrode materials for supercapacitor due to their high surface area, excellent electron conductivity and good chemical stability. The composition and pore structure of carbon materials directly affect their electrochemical performance. In order to further improve their capacitance performance, nitrogen doped carbon materials with excellent electrochemical performance were prepared for the first time by high temperature carbonization with polydopamine as precursor and KOH as activator. The surface morphology, structure and composition of the obtained N-doped porous carbon materials were characterized by scanning electron microscopy(SEM), transmission electron microscopy(TEM), X-ray diffraction spectra(XRD), Fourier transform infrared spectrometer(FT-IR), X-ray photoelectron spectroscopy(XPS) and Raman spectroscopy, respectively. The electrochemical performances were investigated by cyclic voltammetry and galvanostatic charge/discharge in 6 mol/L KOH electrolyte. The results show that the specific capacitance of the material can reach 269 F/g at the current density of 1 A/g due to the synergistic effect of double layer capacitance and pseudocapacitance, and the capacitance still remains 93.5% after 1000 charge-discharge cycles.
2018, 35(4): 484-490
doi: 10.11944/j.issn.1000-0518.2018.04.170107
Abstract:
A bisphenol-A(BPA) TiO2 gel molecularly imprinted electrochemical sensor was fabricated using gold nanoparticles(AuNPs) as sensitivity-enhanced materials based on surface sol-gel and self-assembly methods. AuNPs were characterized by scanning electron microscopy(SEM) and energy dispersive spectroscopy. BPA, TiO2 gel, and BPA-imprinted TiO2 gel were characterized by Fourier transform infrared(FTIR) spectrometry. Under optimal conditions, the sensor exhibits a good linear response from 1.0×10-8 to 1.0×10-5 mol/L for bisphenol A, with correlation coefficient 0.995 and a low detection limit of 0.6×10-8 mol/L(S/N=3). The prepared sensor was successfully applied in the detection of actual sample with 97.4%~103% recoveries.
A bisphenol-A(BPA) TiO2 gel molecularly imprinted electrochemical sensor was fabricated using gold nanoparticles(AuNPs) as sensitivity-enhanced materials based on surface sol-gel and self-assembly methods. AuNPs were characterized by scanning electron microscopy(SEM) and energy dispersive spectroscopy. BPA, TiO2 gel, and BPA-imprinted TiO2 gel were characterized by Fourier transform infrared(FTIR) spectrometry. Under optimal conditions, the sensor exhibits a good linear response from 1.0×10-8 to 1.0×10-5 mol/L for bisphenol A, with correlation coefficient 0.995 and a low detection limit of 0.6×10-8 mol/L(S/N=3). The prepared sensor was successfully applied in the detection of actual sample with 97.4%~103% recoveries.
