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2019 Volume 36 Issue 1
2019, 36(1): 1-9
doi: 10.11944/j.issn.1000-0518.2019.01.180071
Abstract:
Organic light-emitting diodes(OLEDs) have attracted extensive attention throughout the world due to their potential advantages in full-color flat-panel displays such as low voltage, weight, high efficiency and fast response, etc. The development of devices and materials has attracted more attention. According to different electroluminescent mechanism, the materials of OLEDs include fluorescent materials and phosphorescent materials. Recently, blue fluorescent materials become a hot spot in research and play an important role in the developing of OLEDs and possess much more superiority than phosphorescent materials. In this article, we described and summarized recent progress of blue delayed fluorescent materials. The trend and development were finally prospected.
Organic light-emitting diodes(OLEDs) have attracted extensive attention throughout the world due to their potential advantages in full-color flat-panel displays such as low voltage, weight, high efficiency and fast response, etc. The development of devices and materials has attracted more attention. According to different electroluminescent mechanism, the materials of OLEDs include fluorescent materials and phosphorescent materials. Recently, blue fluorescent materials become a hot spot in research and play an important role in the developing of OLEDs and possess much more superiority than phosphorescent materials. In this article, we described and summarized recent progress of blue delayed fluorescent materials. The trend and development were finally prospected.
2019, 36(1): 10-15
doi: 10.11944/j.issn.1000-0518.2019.01.180092
Abstract:
Aryl formic acid cyano aryl methyl esters are important organic synthesis intermediate presently obtained from highly toxic cyanide. In this study, K4[Fe(CN)6] as a green cyanide source combined with acyl chlorine was used to synthesize this type of cyanohydrin ester in a one pot two-steps reaction. Optimized reaction condition was obtained by changing the temperature in second step, the reaction time, the dosages of sodium borohydride and the catalysts, Ten aryl formic acid cyano aryl methyl esters(2a~2j) were synthesized in 61.7%~80.3% yield. Their structures were confirmed by Fourier transform infrared spectrometer(FTIR) and nuclear magnetic resonance spectrometer(NMR). A possible reaction mechanism was also proposed. This method avoids the use of highly toxic cyanide, and benefits from high yield, simple operation, and convenient post-processing.
Aryl formic acid cyano aryl methyl esters are important organic synthesis intermediate presently obtained from highly toxic cyanide. In this study, K4[Fe(CN)6] as a green cyanide source combined with acyl chlorine was used to synthesize this type of cyanohydrin ester in a one pot two-steps reaction. Optimized reaction condition was obtained by changing the temperature in second step, the reaction time, the dosages of sodium borohydride and the catalysts, Ten aryl formic acid cyano aryl methyl esters(2a~2j) were synthesized in 61.7%~80.3% yield. Their structures were confirmed by Fourier transform infrared spectrometer(FTIR) and nuclear magnetic resonance spectrometer(NMR). A possible reaction mechanism was also proposed. This method avoids the use of highly toxic cyanide, and benefits from high yield, simple operation, and convenient post-processing.
2019, 36(1): 16-23
doi: 10.11944/j.issn.1000-0518.2019.01.180048
Abstract:
A green, efficient and simple method for the synthesis of sulfones under combined microwave and ultrasound irradiation was developed. The aromatic methyl phenyl sulfones were synthesized from arylmethyl chlorides and sodium benzenesulfonates in aqueous media under combined microwave and ultrasound irradiation. The effects of microwave power, ultrasonic power, materials molar ratio, substrate concentration and irradiation time were investigated. The optimal conditions for the synthesis of benzyl phenyl sulfone are:microwave power, 40 W; ultrasonic power, 50 W; molar ratio of benzyl chloride and sodium benzene sulfonate, 1:3; reaction time, 5 min. The obtained yield is 83% under these conditions. Compared with the reaction in oil bath, the reaction was accelerated about 42 times. Twenty three sulfones have been successfully synthesized with broad substrate generality.
A green, efficient and simple method for the synthesis of sulfones under combined microwave and ultrasound irradiation was developed. The aromatic methyl phenyl sulfones were synthesized from arylmethyl chlorides and sodium benzenesulfonates in aqueous media under combined microwave and ultrasound irradiation. The effects of microwave power, ultrasonic power, materials molar ratio, substrate concentration and irradiation time were investigated. The optimal conditions for the synthesis of benzyl phenyl sulfone are:microwave power, 40 W; ultrasonic power, 50 W; molar ratio of benzyl chloride and sodium benzene sulfonate, 1:3; reaction time, 5 min. The obtained yield is 83% under these conditions. Compared with the reaction in oil bath, the reaction was accelerated about 42 times. Twenty three sulfones have been successfully synthesized with broad substrate generality.
2019, 36(1): 24-33
doi: 10.11944/j.issn.1000-0518.2019.01.180054
Abstract:
Pillararenes are columnar macrocyclic molecules that are different from crown ethers, calixarenes, and cucurbiturils, and have unique electron-rich cavities and modifiable mouth cavities. They can contain a variety of organic pollutants, and have broad application prospects for the adsorption and removal of organic pollutants. In this paper, the complexation of p-nitrobenzene derivatives with 1, 4-dimethoxy pillar[5]arenes(MeP5A) was studied by nuclear magnetic resonance and ultraviolet titration, and the inclusion constant was determined. On this basis, MeP5A was physically mixed into polyacrylate(PA) emulsion to prepare the MeP5A/polyacrylate(MeP5A/PA) blending emulsion. Then, the blending emulsion was made into the MeP5A/PA nanofiber membrane by the electrospinning technology. The structure and morphology of the MeP5A/PA nanofiber membrane were characterized by infrared spectroscopy and scanning electron microscopy. The MeP5A/PA nanofiber membrane was used for adsorption of four kinds of p-nitrobenzene derivatives. The results reveal that p-nitrophenylacetonitrile holds the strongest complexation intensity with MeP5A[Ka=(6.0±0.3)×102 L/mol]. The introduction of MeP5A into the PA nanofiber membrane increases the adsorption capacity but does not change the fibrous morphology. The optimum adsorption equilibrium time of MeP5A/PA nanofiber membranes is 2 h, and the higher the content of MeP5A in MeP5A/PA nanofiber membranes, the larger the adsorption capacity. When the concentration of MeP5A in the adsorbed solution reaches 4 mmol/L(the corresponding MeP5A mole in the membrane is 1.4×10-2 mmol), the adsorption equilibrium is reached. Then the content of MeP5A continues to increase, and the adsorption capacity does not change much.
Pillararenes are columnar macrocyclic molecules that are different from crown ethers, calixarenes, and cucurbiturils, and have unique electron-rich cavities and modifiable mouth cavities. They can contain a variety of organic pollutants, and have broad application prospects for the adsorption and removal of organic pollutants. In this paper, the complexation of p-nitrobenzene derivatives with 1, 4-dimethoxy pillar[5]arenes(MeP5A) was studied by nuclear magnetic resonance and ultraviolet titration, and the inclusion constant was determined. On this basis, MeP5A was physically mixed into polyacrylate(PA) emulsion to prepare the MeP5A/polyacrylate(MeP5A/PA) blending emulsion. Then, the blending emulsion was made into the MeP5A/PA nanofiber membrane by the electrospinning technology. The structure and morphology of the MeP5A/PA nanofiber membrane were characterized by infrared spectroscopy and scanning electron microscopy. The MeP5A/PA nanofiber membrane was used for adsorption of four kinds of p-nitrobenzene derivatives. The results reveal that p-nitrophenylacetonitrile holds the strongest complexation intensity with MeP5A[Ka=(6.0±0.3)×102 L/mol]. The introduction of MeP5A into the PA nanofiber membrane increases the adsorption capacity but does not change the fibrous morphology. The optimum adsorption equilibrium time of MeP5A/PA nanofiber membranes is 2 h, and the higher the content of MeP5A in MeP5A/PA nanofiber membranes, the larger the adsorption capacity. When the concentration of MeP5A in the adsorbed solution reaches 4 mmol/L(the corresponding MeP5A mole in the membrane is 1.4×10-2 mmol), the adsorption equilibrium is reached. Then the content of MeP5A continues to increase, and the adsorption capacity does not change much.
2019, 36(1): 34-40
doi: 10.11944/j.issn.1000-0518.2019.01.180323
Abstract:
To improve medical protective performance of current commercial surgical clothing under special medical operating conditions and decrease the cross-infection risk of medical personnel and patient due to contacting blood and body fluids carrying pathogens. Inspired by self-cleaning effect of lotus leaf, superhydrophobic/superoleophobic technology is used to modify the commercial surgical clothing surface with fluorine-containing amphiphobic solution for improving its anti-fouling(waterproof, oil-proof, and anti-blood) performance. Scanning electron microscopy and element analysis characterizations verify that the fluorine-containing polymer is fixed on the surgical clothing surface. The waterproof, oil-proof, and anti-blood pollution performances of the modified surgical clothing are conducted, and the results show that the water contact angle of modified surgical clothing surface reaches to (138±2)°, meanwhile the roll angle decreases to 4.0°, indicating the obvious improvement of waterproof performance. Additionally, modified surgical clothing is hard to be wetted by oil droplet for at least 60 seconds. And it allows blood droplet quickly rolling off modified surgical clothing surface by tilting the surface to 20.6° showing low adhesion characteristic to blood droplet. Meanwhile, it keeps excellent water vapor permeability(7.90 g/(min·m2)).
To improve medical protective performance of current commercial surgical clothing under special medical operating conditions and decrease the cross-infection risk of medical personnel and patient due to contacting blood and body fluids carrying pathogens. Inspired by self-cleaning effect of lotus leaf, superhydrophobic/superoleophobic technology is used to modify the commercial surgical clothing surface with fluorine-containing amphiphobic solution for improving its anti-fouling(waterproof, oil-proof, and anti-blood) performance. Scanning electron microscopy and element analysis characterizations verify that the fluorine-containing polymer is fixed on the surgical clothing surface. The waterproof, oil-proof, and anti-blood pollution performances of the modified surgical clothing are conducted, and the results show that the water contact angle of modified surgical clothing surface reaches to (138±2)°, meanwhile the roll angle decreases to 4.0°, indicating the obvious improvement of waterproof performance. Additionally, modified surgical clothing is hard to be wetted by oil droplet for at least 60 seconds. And it allows blood droplet quickly rolling off modified surgical clothing surface by tilting the surface to 20.6° showing low adhesion characteristic to blood droplet. Meanwhile, it keeps excellent water vapor permeability(7.90 g/(min·m2)).
2019, 36(1): 41-50
doi: 10.11944/j.issn.1000-0518.2019.01.180033
Abstract:
Radioactive wastewater generated from nuclear power plants is a complex mixture, in which 137Cs, 90Sr and 60Co are main treatment targets in the radioactive wastewater. In this study, simulated radioactive wastewater was used to investigate the adsorption performance of strong acidic cationic resin IRN97 on Cs removal in the aspects of ion exchange isotherms, kinetic properties and penetration behavior. Meanwhile, the effects of boron and other nuclides on Cs+ were studied as well. The results show that high concentration boron can reduce the adsorption capacity of Cs+. Compared with Sr2+ and Co2+, Cs+ has a higher exchange rate but a lower selectivity. Therefore, the adsorption capacity of Sr2+ and Co2+ is larger than that of Cs+. Increasing the feed concentration of Cs+ can enhance the resin utilization factor in the fixed bed adsorption process.
Radioactive wastewater generated from nuclear power plants is a complex mixture, in which 137Cs, 90Sr and 60Co are main treatment targets in the radioactive wastewater. In this study, simulated radioactive wastewater was used to investigate the adsorption performance of strong acidic cationic resin IRN97 on Cs removal in the aspects of ion exchange isotherms, kinetic properties and penetration behavior. Meanwhile, the effects of boron and other nuclides on Cs+ were studied as well. The results show that high concentration boron can reduce the adsorption capacity of Cs+. Compared with Sr2+ and Co2+, Cs+ has a higher exchange rate but a lower selectivity. Therefore, the adsorption capacity of Sr2+ and Co2+ is larger than that of Cs+. Increasing the feed concentration of Cs+ can enhance the resin utilization factor in the fixed bed adsorption process.
2019, 36(1): 51-57
doi: 10.11944/j.issn.1000-0518.2019.01.180069
Abstract:
Supermicroporous materials possess pore size of 1~2 nm. They are expected to exhibit size-and shape-based separation/catalytic applications, which plays important role in modern industry. It is challenging to find an economic/simple surfactant system for the synthesis of supermicroporous materials. In this work, supermicroporous silica was synthesized using short-chain quaternary ammonium salt(decyltrimethyl ammonium bromide, denoted C10 TAB) surfactant system mixed with fatty acid salts as the templating agents. The samples were characterized by small-angle X-ray diffraction(XRD), N2 adsorption-desorption, Fourier transform infrared spectroscopy(FTIR), scanning electron microscopy(SEM) and transmission electron microscopy(TEM). The results indicate that the length of alkyl chain in co-surfactant, the dosage amount, crystallization temperature have great effects on the regularity of the pore structure. We can obtain highly ordered supermicroporous silica when using sodium octanoate(denoted SO) as co-surfactant in the molar ratio of n(C10TAB):n(Na2SiO3):n(SO):n(H2O)=1:1.5:0.3:800, at the crystallization temperature of 80℃. The calcinated materials possess surface area 1300 m2/g and pore volume 0.49 cm3/g with a pore size distribution centered at about 1.90 nm.
Supermicroporous materials possess pore size of 1~2 nm. They are expected to exhibit size-and shape-based separation/catalytic applications, which plays important role in modern industry. It is challenging to find an economic/simple surfactant system for the synthesis of supermicroporous materials. In this work, supermicroporous silica was synthesized using short-chain quaternary ammonium salt(decyltrimethyl ammonium bromide, denoted C10 TAB) surfactant system mixed with fatty acid salts as the templating agents. The samples were characterized by small-angle X-ray diffraction(XRD), N2 adsorption-desorption, Fourier transform infrared spectroscopy(FTIR), scanning electron microscopy(SEM) and transmission electron microscopy(TEM). The results indicate that the length of alkyl chain in co-surfactant, the dosage amount, crystallization temperature have great effects on the regularity of the pore structure. We can obtain highly ordered supermicroporous silica when using sodium octanoate(denoted SO) as co-surfactant in the molar ratio of n(C10TAB):n(Na2SiO3):n(SO):n(H2O)=1:1.5:0.3:800, at the crystallization temperature of 80℃. The calcinated materials possess surface area 1300 m2/g and pore volume 0.49 cm3/g with a pore size distribution centered at about 1.90 nm.
Hydrolysis of Cellulose by Solid Carbon Sulfonic Acid Supported 1-Butyl-3-methylimidazolium Chloride
2019, 36(1): 58-64
doi: 10.11944/j.issn.1000-0518.2019.01.180049
Abstract:
Cellulose is a renewable resource. Compounds obtained by the hydrolysis of cellulose are of great significance to ease the energy pressure. Herein, the hydrolysis of cellulose catalyzed by solid carbon sulfonic acid supported 1-butyl-3-methylimidazolium chloride is reported. The solid carbon sulfonic acid obtained from bamboo biomass by pre-carbonization at 700℃ and sulfonation at 150℃ was used as the matrix. Ionic liquid functionalized solid carbon sulfonic acid catalyst was obtained by loading 1-butyl-3-methylimidazolium chloride. The results show that the total reducing sugar yield under optimal conditions is increased by 15.2% relative to the total reducing sugar yield by exploiting solid carbon sulfonic acid. The catalyst still exhibits good performance after recycling.
Cellulose is a renewable resource. Compounds obtained by the hydrolysis of cellulose are of great significance to ease the energy pressure. Herein, the hydrolysis of cellulose catalyzed by solid carbon sulfonic acid supported 1-butyl-3-methylimidazolium chloride is reported. The solid carbon sulfonic acid obtained from bamboo biomass by pre-carbonization at 700℃ and sulfonation at 150℃ was used as the matrix. Ionic liquid functionalized solid carbon sulfonic acid catalyst was obtained by loading 1-butyl-3-methylimidazolium chloride. The results show that the total reducing sugar yield under optimal conditions is increased by 15.2% relative to the total reducing sugar yield by exploiting solid carbon sulfonic acid. The catalyst still exhibits good performance after recycling.
2019, 36(1): 65-74
doi: 10.11944/j.issn.1000-0518.2019.01.180040
Abstract:
The foam-like graphitic carbon nitride(g-C3N4) was synthesized by using melamine as the raw material and cheap sepiolite as the hard template, respectively. The as-prepared samples were characterized by transmission electron microscopy(TEM), X-ray diffraction(XRD), Fourier transform infrared(FT-IR) spectrometry, Brunauer-Emmett-Teller(BET) method, ultraviolet-visible diffuse reflectance spectroscopy(UV-Vis DRS), photoluminescence(PL) spectroscopy and electrochemical measurements, and the photocatalytic activity was evaluated by visible light driven hydrogen evolution. The results show that polydopamine can act as adhesives, which can improve the combined degree between the template and melamine, leading to the increase of the specific surface area of foam-like graphitic carbon nitride. Furthermore, the specific surface area of the obtained sample increases with the increase of polydopamine-modified sepiolite, when the mass ratio of polydopamine-modified sepiolite and melamine is 2:1, the specific surface area of the foam like g-C3N4 is as high as 389.2 m2/g and the visible light driven H2 evolution rate can reach up to 1061.87 μmol/(g·h), which is~7 times greater than that of bulk g-C3N4(151.24 μmol/(g·h)) and 2.6 times higher than that of g-C3N4 synthesized by unmodified sepiolite, respectively. This indicates that the foam-like g-C3N4 with a large surface area can provide more active sites and improve the diffusion process of multi-phase photocatalytic reaction, enhancing the separation efficiency of photogenerated electrons and holes. Additionally, the unique cavity structure can also effectively improve the utilization of light, leading to a significant improvement in the photocatalytic performance.
The foam-like graphitic carbon nitride(g-C3N4) was synthesized by using melamine as the raw material and cheap sepiolite as the hard template, respectively. The as-prepared samples were characterized by transmission electron microscopy(TEM), X-ray diffraction(XRD), Fourier transform infrared(FT-IR) spectrometry, Brunauer-Emmett-Teller(BET) method, ultraviolet-visible diffuse reflectance spectroscopy(UV-Vis DRS), photoluminescence(PL) spectroscopy and electrochemical measurements, and the photocatalytic activity was evaluated by visible light driven hydrogen evolution. The results show that polydopamine can act as adhesives, which can improve the combined degree between the template and melamine, leading to the increase of the specific surface area of foam-like graphitic carbon nitride. Furthermore, the specific surface area of the obtained sample increases with the increase of polydopamine-modified sepiolite, when the mass ratio of polydopamine-modified sepiolite and melamine is 2:1, the specific surface area of the foam like g-C3N4 is as high as 389.2 m2/g and the visible light driven H2 evolution rate can reach up to 1061.87 μmol/(g·h), which is~7 times greater than that of bulk g-C3N4(151.24 μmol/(g·h)) and 2.6 times higher than that of g-C3N4 synthesized by unmodified sepiolite, respectively. This indicates that the foam-like g-C3N4 with a large surface area can provide more active sites and improve the diffusion process of multi-phase photocatalytic reaction, enhancing the separation efficiency of photogenerated electrons and holes. Additionally, the unique cavity structure can also effectively improve the utilization of light, leading to a significant improvement in the photocatalytic performance.
2019, 36(1): 75-82
doi: 10.11944/j.issn.1000-0518.2019.01.180034
Abstract:
NiO nanosheets have been synthesized via a facile solvothermal route using water-ethylene glycol as solvent and polyvinyl pyrrolidone(PVP) as surfactant. These NiO nanosheets were interweaved with each other to form hierarchical flower-shaped structures. Nanocubes and nanospheres were also obtained through changing the reaction temperature and solvent. The electrochemical tests were conducted using a three-electrode system in 6 mol/L KOH with the as-synthesized NiO as the working electrode. Electrochemical properties were characterized by cyclic voltammetry, galvanostatic charge/discharge measurements, and electrochemical impedance spectroscopy. NiO nanosheets exhibit the highest specific capacitance(402 F/g at current density of 0.5 A/g) and the best rate capability(80.1% capacitance retention from 0.5 A/g to 4 A/g). NiO nanosheets also show excellent cycle stability, only lost 9.7% after 1000 cycles.
NiO nanosheets have been synthesized via a facile solvothermal route using water-ethylene glycol as solvent and polyvinyl pyrrolidone(PVP) as surfactant. These NiO nanosheets were interweaved with each other to form hierarchical flower-shaped structures. Nanocubes and nanospheres were also obtained through changing the reaction temperature and solvent. The electrochemical tests were conducted using a three-electrode system in 6 mol/L KOH with the as-synthesized NiO as the working electrode. Electrochemical properties were characterized by cyclic voltammetry, galvanostatic charge/discharge measurements, and electrochemical impedance spectroscopy. NiO nanosheets exhibit the highest specific capacitance(402 F/g at current density of 0.5 A/g) and the best rate capability(80.1% capacitance retention from 0.5 A/g to 4 A/g). NiO nanosheets also show excellent cycle stability, only lost 9.7% after 1000 cycles.
2019, 36(1): 83-90
doi: 10.11944/j.issn.1000-0518.2019.01.180059
Abstract:
The ZnMgAl hydrotalcite-like compounds(HTLCs) supported bismuth oxyiodide(BiOI)(BiOI/ZnMgAl-HTLCs) visible light photocatalyst was prepared by hydrothermal method. The effects of BiOI loading mass fraction, reaction temperature, reaction time, and addition sequence on the structure and morphology of the BiOI/ZnMgAl-HTLCs photocatalyst were investigated by X-ray diffraction(XRD), scanning electron microscopy(SEM) and Fourier transform infrared spectroscopy(FTIR). The results show that BiOI/ZnMgAl-HTLCs with high crystallinity and good morphology can be obtained by firstly adding BiOI in 40% mass fraction to ZnMgAl-HTLCs at 140℃, and keeping reaction for 24 h.
The ZnMgAl hydrotalcite-like compounds(HTLCs) supported bismuth oxyiodide(BiOI)(BiOI/ZnMgAl-HTLCs) visible light photocatalyst was prepared by hydrothermal method. The effects of BiOI loading mass fraction, reaction temperature, reaction time, and addition sequence on the structure and morphology of the BiOI/ZnMgAl-HTLCs photocatalyst were investigated by X-ray diffraction(XRD), scanning electron microscopy(SEM) and Fourier transform infrared spectroscopy(FTIR). The results show that BiOI/ZnMgAl-HTLCs with high crystallinity and good morphology can be obtained by firstly adding BiOI in 40% mass fraction to ZnMgAl-HTLCs at 140℃, and keeping reaction for 24 h.
2019, 36(1): 91-96
doi: 10.11944/j.issn.1000-0518.2019.01.180080
Abstract:
In order to improve photocalytic property and enhance magnetism of BiFeO3(BFO), nano-sized Bi0.95Ho0.05FeO3(BHFO) particles were prepared through thermal decomposition of coordination precursor at 500℃. The material obtained was characterized by X-ray diffractometer(XRD), Fourier transfom infrared(FT-IR) spectrometer, dynamic reflectance spectrometer(DRS), vibrating sample magnetometer(VSM), and Zeta potential analyser. It exhibits rhombohedral R3c phase with a band gap of 1.90 eV, and its magnetism is 5 times stronger than BFO. With methyl orange(MO) as the degradation model, the influence factors on photocatalytic activity of BHFO was found to be affected by the oxidization and acid-base property of anions. At last, BHFO exhibits good photocatalytic stability and can be recovered by magnetical separation.
In order to improve photocalytic property and enhance magnetism of BiFeO3(BFO), nano-sized Bi0.95Ho0.05FeO3(BHFO) particles were prepared through thermal decomposition of coordination precursor at 500℃. The material obtained was characterized by X-ray diffractometer(XRD), Fourier transfom infrared(FT-IR) spectrometer, dynamic reflectance spectrometer(DRS), vibrating sample magnetometer(VSM), and Zeta potential analyser. It exhibits rhombohedral R3c phase with a band gap of 1.90 eV, and its magnetism is 5 times stronger than BFO. With methyl orange(MO) as the degradation model, the influence factors on photocatalytic activity of BHFO was found to be affected by the oxidization and acid-base property of anions. At last, BHFO exhibits good photocatalytic stability and can be recovered by magnetical separation.
2019, 36(1): 97-106
doi: 10.11944/j.issn.1000-0518.2019.01.180065
Abstract:
The transition metal phthalocyanine has a high catalytic activity for oxygen reduction. MnO2 can catalyze the oxygen reduction reaction. However, the use of transition metal phthalocyanine and MnO2 as dual catalysts for oxygen reduction is quite few. Four types of carbon nanotubes supported tetra-nitro-metal phthalocyanines assemblies(CNT/TNMPc) were synthesized by phthalic anhydride-urea method. Dual catalyst CNT/TNMPc-MnO2 was prepared via adding γ-MnO2 into CNT/TNMPc. The optimal ratio of CNT/TNMPc to MnO2 was obtained by means of cyclic voltammetry. Effects of central metal ions of CNT/TNMPc on the catalytic performance for oxygen reduction reactivity were investigated. The results show that the catalytic efficiency order of the dual catalyst for oxygen reduction reactivity is CNT/TNFePc-MnO2 > CNT/TNCoPc-MnO2 > CNT/TNNiPc-MnO2 > CNT/TNCuPc-MnO2. All of those suggest that the catalytic activity of dual catalysts for oxygen reduction reaction is mainly affected by the nature of metal ions. In addition, the anti methanol performance of dual catalyst was tested in 0.1 mol/L KOH+0.5 mol/L CH3OH electrolyte solution. The results indicate that methanol-tolerant abilities of the CNT/TNMPc-MnO2 are excellent.
The transition metal phthalocyanine has a high catalytic activity for oxygen reduction. MnO2 can catalyze the oxygen reduction reaction. However, the use of transition metal phthalocyanine and MnO2 as dual catalysts for oxygen reduction is quite few. Four types of carbon nanotubes supported tetra-nitro-metal phthalocyanines assemblies(CNT/TNMPc) were synthesized by phthalic anhydride-urea method. Dual catalyst CNT/TNMPc-MnO2 was prepared via adding γ-MnO2 into CNT/TNMPc. The optimal ratio of CNT/TNMPc to MnO2 was obtained by means of cyclic voltammetry. Effects of central metal ions of CNT/TNMPc on the catalytic performance for oxygen reduction reactivity were investigated. The results show that the catalytic efficiency order of the dual catalyst for oxygen reduction reactivity is CNT/TNFePc-MnO2 > CNT/TNCoPc-MnO2 > CNT/TNNiPc-MnO2 > CNT/TNCuPc-MnO2. All of those suggest that the catalytic activity of dual catalysts for oxygen reduction reaction is mainly affected by the nature of metal ions. In addition, the anti methanol performance of dual catalyst was tested in 0.1 mol/L KOH+0.5 mol/L CH3OH electrolyte solution. The results indicate that methanol-tolerant abilities of the CNT/TNMPc-MnO2 are excellent.
2019, 36(1): 107-113
doi: 10.11944/j.issn.1000-0518.2019.01.180041
Abstract:
In order to investigate electrochemical process at elevated temperature, a high temperature thin-layer cell(HTC) was constructed for in situ infrared(IR) spectroelectrochemistry. It works very well in the temperature range from ambient to 373 K(depend on boiling point of solvent) with the control precision within ±0.5 K to apply for room-temp and high-temp in situ IR spectroelectrochemistry. The cell can be facilely cleaned and conveniently manipulated in both aqueous and non-aqueous system. The electrochemical and IR performance were characterized with K3[Fe(CN)6] in aqueous and with benzoquinone(BQ) in ionic liquid BMIMPF6 by cyclic voltammetry and in situ IR spectroelectrochemistry at various temperature. Experimental results suggest that the cell has an excellent electrochemical performance within wider range of temperature, and good signal-noise ratio for IR absorption peaks during cyclic voltammetry(CV) scan. In conclusion, HTC has a promising application in electrochemical process in which the temperature plays an important role.
In order to investigate electrochemical process at elevated temperature, a high temperature thin-layer cell(HTC) was constructed for in situ infrared(IR) spectroelectrochemistry. It works very well in the temperature range from ambient to 373 K(depend on boiling point of solvent) with the control precision within ±0.5 K to apply for room-temp and high-temp in situ IR spectroelectrochemistry. The cell can be facilely cleaned and conveniently manipulated in both aqueous and non-aqueous system. The electrochemical and IR performance were characterized with K3[Fe(CN)6] in aqueous and with benzoquinone(BQ) in ionic liquid BMIMPF6 by cyclic voltammetry and in situ IR spectroelectrochemistry at various temperature. Experimental results suggest that the cell has an excellent electrochemical performance within wider range of temperature, and good signal-noise ratio for IR absorption peaks during cyclic voltammetry(CV) scan. In conclusion, HTC has a promising application in electrochemical process in which the temperature plays an important role.
2019, 36(1): 114-119
doi: 10.11944/j.issn.1000-0518.2019.01.180321
Abstract:
The impedance analysis quartz crystal microbalance has many advantages such as wide application range and more parameters, but the resonance frequency of the quartz crystal obtained by the impedance analysis method takes a long time and has poor real-time performance. In response to this problem, we analyzed the process of data fitting when using the least squares method and proposed a fast detection method for quartz crystal resonant frequency measurement. By adjusting the data coordinate system, the calculation time used for the fitting process reduced obviously. The new method was verified by experiments, compared with the traditional least squares method, the efficiency of the algorithm for calculating the resonant frequency was improved by four times, and the calculation accuracy was higher. It means the new method has high practical value.
The impedance analysis quartz crystal microbalance has many advantages such as wide application range and more parameters, but the resonance frequency of the quartz crystal obtained by the impedance analysis method takes a long time and has poor real-time performance. In response to this problem, we analyzed the process of data fitting when using the least squares method and proposed a fast detection method for quartz crystal resonant frequency measurement. By adjusting the data coordinate system, the calculation time used for the fitting process reduced obviously. The new method was verified by experiments, compared with the traditional least squares method, the efficiency of the algorithm for calculating the resonant frequency was improved by four times, and the calculation accuracy was higher. It means the new method has high practical value.
2019, 36(1): 120-122
doi: 10.11944/j.issn.1000-0518.2019.01.180212
Abstract:
Methoxypolyethylene glycol olefin was obtained by olefination of methoxypolyethylene glycol, and followed by ozonation to give methoxypolyethylene glycol aldehyde derivative. The properties of products were characterized by nuclear magnetic resonance spectroscopy(NMR) and matrix-assisted laser desorption/ionization time of flight mass spectrometry(MALDI-TOF-MS). The results show that the product has high purity and no by-products. The yields of methoxy polyethylene glycol acetaldehyde and polyethylene glycol propionaldehyde are as high as 98% and 99%, respectively, and the degrees of substitution are 90.87%~99.91% and 98%~100%, respectively.
Methoxypolyethylene glycol olefin was obtained by olefination of methoxypolyethylene glycol, and followed by ozonation to give methoxypolyethylene glycol aldehyde derivative. The properties of products were characterized by nuclear magnetic resonance spectroscopy(NMR) and matrix-assisted laser desorption/ionization time of flight mass spectrometry(MALDI-TOF-MS). The results show that the product has high purity and no by-products. The yields of methoxy polyethylene glycol acetaldehyde and polyethylene glycol propionaldehyde are as high as 98% and 99%, respectively, and the degrees of substitution are 90.87%~99.91% and 98%~100%, respectively.
