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2013 Volume 30 Issue 9
2013, 30(9): 977-985
doi: 10.3724/SP.J.1095.2013.20596
Abstract:
Although organic materials have been widely utilized for the fabrications of organic solar cells as they are inexpensive,easily prepared and compatible with substrates,the development of organic solar cells has been hindered mainly due to their low carrier mobility,poor stability and unsatisfactory matching with the solar spectrum.On the other hand,inorganic materials have high electron mobility and absorption spectra matching with the solar spectrum. Therefore the power conversion efficiency of organic solar cells is still not competitive with those of inorganic solar cells. If the advantages of both organic and inorganic materials could be combined,the performance of organic solar cells would be enhanced. At present,some progresses have been made in inorganic-organic hybird solar cells. Usually,the inorganic materials were used in the acceptor layer,cathode buffer layer and anode buffer layer to improve the energy conversion efficiency of organic solar cells. In this article we discussed the applications of some inorganic materials in organic solar cells and the recent research progresses as well as the perspectives in this field.
Although organic materials have been widely utilized for the fabrications of organic solar cells as they are inexpensive,easily prepared and compatible with substrates,the development of organic solar cells has been hindered mainly due to their low carrier mobility,poor stability and unsatisfactory matching with the solar spectrum.On the other hand,inorganic materials have high electron mobility and absorption spectra matching with the solar spectrum. Therefore the power conversion efficiency of organic solar cells is still not competitive with those of inorganic solar cells. If the advantages of both organic and inorganic materials could be combined,the performance of organic solar cells would be enhanced. At present,some progresses have been made in inorganic-organic hybird solar cells. Usually,the inorganic materials were used in the acceptor layer,cathode buffer layer and anode buffer layer to improve the energy conversion efficiency of organic solar cells. In this article we discussed the applications of some inorganic materials in organic solar cells and the recent research progresses as well as the perspectives in this field.
2013, 30(9): 986-992
doi: 10.3724/SP.J.1095.2013.20501
Abstract:
Four monomers of polybenzoxazole having the structure of bisphenol aromatic ether,bis(3-amino-hydroxyphenyl) bisphenol ether,were prepared from bisphenols and 4-chloro(or bromo)-phenol by successive 4 steps of synthetic routes including benzyl protection,Ullmann reaction, selective nitrification and reduction-deprotection. The effect of reaction conditions on the Ullmann reaction was investigated. The high region selection of the nitrification is confirmed. The process of after-treatment of the reduction-deprotection was optimized and the quality and yield of the product were improved. The total yield of 4 steps reaction can reach up to 54.0%. The target compound and its intermediates were characterized by means of IR,1H NMR and HRMS.
Four monomers of polybenzoxazole having the structure of bisphenol aromatic ether,bis(3-amino-hydroxyphenyl) bisphenol ether,were prepared from bisphenols and 4-chloro(or bromo)-phenol by successive 4 steps of synthetic routes including benzyl protection,Ullmann reaction, selective nitrification and reduction-deprotection. The effect of reaction conditions on the Ullmann reaction was investigated. The high region selection of the nitrification is confirmed. The process of after-treatment of the reduction-deprotection was optimized and the quality and yield of the product were improved. The total yield of 4 steps reaction can reach up to 54.0%. The target compound and its intermediates were characterized by means of IR,1H NMR and HRMS.
2013, 30(9): 993-998
doi: 10.3724/SP.J.1095.2013.20507
Abstract:
A series of novel 3,6(8)-disubstituted 2,4-dihydro-1,3-benzoxazines was synthesized by Mannich reactions of substituted anilines with paraformaldehyde and substituted phenols in the absence of catalyst. The results show that substituted phenols and anilines with electron-donating groups on the phenyl ring give higher yields than those with electron-withdrawing groups. The structures of the products were characterized by 1H NMR,13C NMR,IR and MS. The fungicidal activity of the title compounds was preliminarily evaluated.Compounds 4j and 4d show 86.1% and 81.5% activity against Sclerotonia sclerotiorum at the concentration of 25 mg/L,respectively. Compound 4i exhibits 81.6% activity against Botrytis cinerea.
A series of novel 3,6(8)-disubstituted 2,4-dihydro-1,3-benzoxazines was synthesized by Mannich reactions of substituted anilines with paraformaldehyde and substituted phenols in the absence of catalyst. The results show that substituted phenols and anilines with electron-donating groups on the phenyl ring give higher yields than those with electron-withdrawing groups. The structures of the products were characterized by 1H NMR,13C NMR,IR and MS. The fungicidal activity of the title compounds was preliminarily evaluated.Compounds 4j and 4d show 86.1% and 81.5% activity against Sclerotonia sclerotiorum at the concentration of 25 mg/L,respectively. Compound 4i exhibits 81.6% activity against Botrytis cinerea.
2013, 30(9): 999-1004
doi: 10.3724/SP.J.1095.2013.20541
Abstract:
Six novel N-(2-(cyano(4,6-dimethoxypyrimidin-2-yl) methyl) phenyl) substitued amide derivatives were synthesized using 2-(2-nitrophenyl) acetonitrile and 4,6-dimethoxy-2-(methylsulfonyl) pyrimidine as starting materials by condensation reaction,reduction reaction and acylation reaction,respectively. The structures of all synthesized compounds were determined by 1H NMR,MS and elemental analysis techniques. As-synthesized compounds did not show herbicidal activities at 150 g/hm2. The antibacterial activity test indicated that some of them exhibited certain inhibitory activities against Sphaerotheca fuliginea and Rhizoctonia solani, respectively at 200 mg/L. The inhibition rate of compound 4d against Rhizoctonia solani was 72.3% at 200 mg/L.
Six novel N-(2-(cyano(4,6-dimethoxypyrimidin-2-yl) methyl) phenyl) substitued amide derivatives were synthesized using 2-(2-nitrophenyl) acetonitrile and 4,6-dimethoxy-2-(methylsulfonyl) pyrimidine as starting materials by condensation reaction,reduction reaction and acylation reaction,respectively. The structures of all synthesized compounds were determined by 1H NMR,MS and elemental analysis techniques. As-synthesized compounds did not show herbicidal activities at 150 g/hm2. The antibacterial activity test indicated that some of them exhibited certain inhibitory activities against Sphaerotheca fuliginea and Rhizoctonia solani, respectively at 200 mg/L. The inhibition rate of compound 4d against Rhizoctonia solani was 72.3% at 200 mg/L.
2013, 30(9): 1005-1009
doi: 10.3724/SP.J.1095.2013.20523
Abstract:
A FeCl3·6H2O-catalyzed cross-Aldol condensation of 3-methylcyclohexanone and ethyl pyruvate was developed for the synthesis of mintlactone. The resultant ethyl 2-(4-methyl-2-oxocyclohexylidene) propionate and 7a-hydroxymintlactone were saponified by NaOH,reduced by NaBH4,and acidified to yield (±)-mintlactone in 51% yield. Regioselectivity of the keto-to-enol isomerization of 3-methylcyclohexanone and isomer ratio of (±)-mintlactone/(±)-isomintlactone in crude products were discussed.
A FeCl3·6H2O-catalyzed cross-Aldol condensation of 3-methylcyclohexanone and ethyl pyruvate was developed for the synthesis of mintlactone. The resultant ethyl 2-(4-methyl-2-oxocyclohexylidene) propionate and 7a-hydroxymintlactone were saponified by NaOH,reduced by NaBH4,and acidified to yield (±)-mintlactone in 51% yield. Regioselectivity of the keto-to-enol isomerization of 3-methylcyclohexanone and isomer ratio of (±)-mintlactone/(±)-isomintlactone in crude products were discussed.
2013, 30(9): 1010-1016
doi: 10.3724/SP.J.1095.2013.20512
Abstract:
One lamellar coordination compound,Cu(DMBC)2(H2O)2 (DMBC=2-(3,5-dimethylphenoxy) acetic acid),was hydrothermally synthesized using CuCl2 and 2-(3,5-dimethylphenoxy) acetic acid(DMBC). The ligand,DMBC,was obtained by the reaction of 3,5-dimethylphenol with 2-chloroacetic acid using polyethylene glycol(PEG-400) as the phase transfer catalyst. The compound was characterized by elemental analysis,IR and single crystal X-ray diffraction.The title compound crystallizes in the monoclinic system with space group P21/c,a=1.526(2) nm,b=0.7092(11) nm,c=1.0942(17)nm,β=104.567(15)°,V=1.146(3)nm3,Z=2,F(000)=478. The centric Cu(Ⅱ) cation situates in the center of a slightly deformed quadrilateral plane and coordinated with two oxygen atoms from two ligands and two water molecules. It further self-assembles into a 2D lamellar supramolecular frameworks via π-π interactions and hydrogen bondings. A quantization calculation of the title compound was carried out at the B3LYP/6-31G level using Gussian 03 program,and the atomic charge distribution within the molecule was given. The calculation results are comparable to the measured results. Its activities toward the rapeseed germination and antibacterial action have been evaluated.CCDC:909139
One lamellar coordination compound,Cu(DMBC)2(H2O)2 (DMBC=2-(3,5-dimethylphenoxy) acetic acid),was hydrothermally synthesized using CuCl2 and 2-(3,5-dimethylphenoxy) acetic acid(DMBC). The ligand,DMBC,was obtained by the reaction of 3,5-dimethylphenol with 2-chloroacetic acid using polyethylene glycol(PEG-400) as the phase transfer catalyst. The compound was characterized by elemental analysis,IR and single crystal X-ray diffraction.The title compound crystallizes in the monoclinic system with space group P21/c,a=1.526(2) nm,b=0.7092(11) nm,c=1.0942(17)nm,β=104.567(15)°,V=1.146(3)nm3,Z=2,F(000)=478. The centric Cu(Ⅱ) cation situates in the center of a slightly deformed quadrilateral plane and coordinated with two oxygen atoms from two ligands and two water molecules. It further self-assembles into a 2D lamellar supramolecular frameworks via π-π interactions and hydrogen bondings. A quantization calculation of the title compound was carried out at the B3LYP/6-31G level using Gussian 03 program,and the atomic charge distribution within the molecule was given. The calculation results are comparable to the measured results. Its activities toward the rapeseed germination and antibacterial action have been evaluated.CCDC:909139
2013, 30(9): 1017-1022
doi: 10.3724/SP.J.1095.2013.20492
Abstract:
The activated carbon was prepared from pyrolysis bio-char of sawdust by chemical activation with KOH. The influences of the mass ratio of alkali to carbon,activation temperature and hold time toward the methylene blue adsorption on activated carbon were investigated. After this,the structure and properties of raw materials and activated carbon were characterized by nitrogen adsorption,XRD and FTIR spectroscopies. The results show that the methylene blue adsorption on activated carbon reaches to 255 mg/g at an alkali to carbon mass ratio of 1.5,an activation temperature of 750℃ and a hold time of 2 h. The activated carbon possesses a large apparent surface area(SBET=1514 m2/g) and high adsorption pore volume(V=0.821 cm3/g) with average pore size diameter of 2.170 nm.
The activated carbon was prepared from pyrolysis bio-char of sawdust by chemical activation with KOH. The influences of the mass ratio of alkali to carbon,activation temperature and hold time toward the methylene blue adsorption on activated carbon were investigated. After this,the structure and properties of raw materials and activated carbon were characterized by nitrogen adsorption,XRD and FTIR spectroscopies. The results show that the methylene blue adsorption on activated carbon reaches to 255 mg/g at an alkali to carbon mass ratio of 1.5,an activation temperature of 750℃ and a hold time of 2 h. The activated carbon possesses a large apparent surface area(SBET=1514 m2/g) and high adsorption pore volume(V=0.821 cm3/g) with average pore size diameter of 2.170 nm.
2013, 30(9): 1023-1029
doi: 10.3724/SP.J.1095.2013.20522
Abstract:
Magnetic Fe3O4/ZnO core-shell nano-materials were successfully prepared by using a two-step procedure with coprecipitation and annealing treatment. The material composition,morphology and magnetic properties were examined and verified by means of X-ray diffraction(XRD),infrared spectroscopy(IR),transmission electron microscopy(TEM) and vibrating sample magnetometer(VSM). The photocatalytic degradation activity of the compound in the sunlight was evaluated by xenon lamp irradiating on tetracycline(TC), doxycycline(DC) and oxytetracycline(OTC),three tetracycline antibiotics,and the best performance of photocatalytic degradation activity was tailored by the concentration of zinc precursor. The results show that ZnO coated on the surface of Fe3O4 gradually forms 100 nm conical structure with increasing Zn2+ concentration. When Zn2+ concentration is 0.5 mol/L,the max degradation rate of TC,DC and OTC antibiotics is 85%,78% and 64%,respectively. On the basis of the above points,the synthesized magnetic Fe3O4/ZnO coreshell materials can be used for water antibiotics removal,and it will be a new composite photocatalyst with high catalytic activity and recover ability.
Magnetic Fe3O4/ZnO core-shell nano-materials were successfully prepared by using a two-step procedure with coprecipitation and annealing treatment. The material composition,morphology and magnetic properties were examined and verified by means of X-ray diffraction(XRD),infrared spectroscopy(IR),transmission electron microscopy(TEM) and vibrating sample magnetometer(VSM). The photocatalytic degradation activity of the compound in the sunlight was evaluated by xenon lamp irradiating on tetracycline(TC), doxycycline(DC) and oxytetracycline(OTC),three tetracycline antibiotics,and the best performance of photocatalytic degradation activity was tailored by the concentration of zinc precursor. The results show that ZnO coated on the surface of Fe3O4 gradually forms 100 nm conical structure with increasing Zn2+ concentration. When Zn2+ concentration is 0.5 mol/L,the max degradation rate of TC,DC and OTC antibiotics is 85%,78% and 64%,respectively. On the basis of the above points,the synthesized magnetic Fe3O4/ZnO coreshell materials can be used for water antibiotics removal,and it will be a new composite photocatalyst with high catalytic activity and recover ability.
2013, 30(9): 1030-1035
doi: 10.3724/SP.J.1095.2013.20496
Abstract:
The esterification between oleic acid and alkyl alcohols in solvent-free systems were catalyzed by an immobilized lipase from Candida sp.99-125. The effects of several factors including enzyme concentration,temperature,molar ratio of oleic acid to alkyl alcohols,and structure of alcohols have been also investigated. The results indicated that the reactions catalyzed by lipase at 20℃ with the presence of 3% (mass fraction) lipase,a 1:1 molar ratio of oleic acid to alcohols,afforded products in high yields. Methanol has certain toxicity on the activity of the lipase. The enzyme showed high selectivity to primary alcohols and low selectivity to secondary and tertiary alcohols because of the sterical effect. It showed high activity to long chain fatty acids and low activity to polybasic acids and polyhydric alcohols with branched chain. The lipase showed no appreciable loss in activity after being continuously operated for 5 times. The enzymatic synthesis gave purer products,compared with the conventional chemical system.
The esterification between oleic acid and alkyl alcohols in solvent-free systems were catalyzed by an immobilized lipase from Candida sp.99-125. The effects of several factors including enzyme concentration,temperature,molar ratio of oleic acid to alkyl alcohols,and structure of alcohols have been also investigated. The results indicated that the reactions catalyzed by lipase at 20℃ with the presence of 3% (mass fraction) lipase,a 1:1 molar ratio of oleic acid to alcohols,afforded products in high yields. Methanol has certain toxicity on the activity of the lipase. The enzyme showed high selectivity to primary alcohols and low selectivity to secondary and tertiary alcohols because of the sterical effect. It showed high activity to long chain fatty acids and low activity to polybasic acids and polyhydric alcohols with branched chain. The lipase showed no appreciable loss in activity after being continuously operated for 5 times. The enzymatic synthesis gave purer products,compared with the conventional chemical system.
2013, 30(9): 1036-1041
doi: 10.3724/SP.J.1095.2013.20555
Abstract:
The silver salt of 3,6-bis(1-H-1,2,3,4-tetrazole-5-amino)-1,2,4,5-tetrazine(BTATz)(Ag2(BTATz)·2H2O) was synthesized by two steps,and its structure was characterized by elemental analysis,X-ray fluorescence diffraction and FT-IR spectra. The thermal behavior of the compound was studied under non-isothermal conditions using DSC and TG-DTG methods,the result indicated that the thermal decomposition comprises of one endothermic and two exothermic stages,the non-isothermal decomposition reaction kinetics equation of the main exothermic stage can be expressed as:dα/dt=1014.29×{3(1-α)[-ln(1-α)]1/4/4} exp(-2.10 × 104/T). The values of the self-accelerating decomposition temperature(TSADT),critical temperatures of thermal explosion(Tb),thermal ignition temperature(TTIT) and the adiabatic time-to-explosion(tTIAD) for the compound were calculated as 517.10 K,580.12 K,531.00 K and 90.32 s,respectively. In addition,its thermal safety was evaluated.
The silver salt of 3,6-bis(1-H-1,2,3,4-tetrazole-5-amino)-1,2,4,5-tetrazine(BTATz)(Ag2(BTATz)·2H2O) was synthesized by two steps,and its structure was characterized by elemental analysis,X-ray fluorescence diffraction and FT-IR spectra. The thermal behavior of the compound was studied under non-isothermal conditions using DSC and TG-DTG methods,the result indicated that the thermal decomposition comprises of one endothermic and two exothermic stages,the non-isothermal decomposition reaction kinetics equation of the main exothermic stage can be expressed as:dα/dt=1014.29×{3(1-α)[-ln(1-α)]1/4/4} exp(-2.10 × 104/T). The values of the self-accelerating decomposition temperature(TSADT),critical temperatures of thermal explosion(Tb),thermal ignition temperature(TTIT) and the adiabatic time-to-explosion(tTIAD) for the compound were calculated as 517.10 K,580.12 K,531.00 K and 90.32 s,respectively. In addition,its thermal safety was evaluated.
2013, 30(9): 1042-1047
doi: 10.3724/SP.J.1095.2013.20438
Abstract:
N-Acyl-L-serine based surfactants were synthesized by using L-serine and three kinds of acyl chloride. The chemical structures of the prepared compounds were confirmed by 1H NMR,ESI-MS and elemental analysis. The aggregation behaviors of sodium N-acyl-L-serine in water were investigated by surface tension at temperatures of 298 K,308 K,318 K,328 K,respectively. From these measurements,the critical micelle concentrations(cmc),the surface tension at the cmc(γcmc),saturated adsorption capacity Γ max and the standard thermodynamic parameters of micellization were calculated respectively. In term of the equation of cmc and temperature,the thermodynamic parameters by using phase separation model indicate that the standard Gibbs free energy (△Gmo) of micellization is negative,the absolute value of the standard enthalpy of micellization, △Hmo,is much smaller than the that of T△Smo in the aqueous solution. Temperature-dependant change of the standard enthalpy of micellization shows the micellization process is enthopy-driven. With the temperature increasing,the micellization is enthalpy-entropy compensated.
N-Acyl-L-serine based surfactants were synthesized by using L-serine and three kinds of acyl chloride. The chemical structures of the prepared compounds were confirmed by 1H NMR,ESI-MS and elemental analysis. The aggregation behaviors of sodium N-acyl-L-serine in water were investigated by surface tension at temperatures of 298 K,308 K,318 K,328 K,respectively. From these measurements,the critical micelle concentrations(cmc),the surface tension at the cmc(γcmc),saturated adsorption capacity Γ max and the standard thermodynamic parameters of micellization were calculated respectively. In term of the equation of cmc and temperature,the thermodynamic parameters by using phase separation model indicate that the standard Gibbs free energy (△Gmo) of micellization is negative,the absolute value of the standard enthalpy of micellization, △Hmo,is much smaller than the that of T△Smo in the aqueous solution. Temperature-dependant change of the standard enthalpy of micellization shows the micellization process is enthopy-driven. With the temperature increasing,the micellization is enthalpy-entropy compensated.
2013, 30(9): 1048-1053
doi: 10.3724/SP.J.1095.2013.20535
Abstract:
To replace the common emulsifiers and solvents,the mix-emulsifier of benzyl starch ether in combination with alkyl polyglycoside and solvent of methyl oleate were used in preparation of 10% cyhalofopbutyl aqueous emulsions. The structure of benzyl starch ether was characterized by FTIR and UV spectroscopies in case of benzyl carboxymethy. The effects of different processing parameters,including the concentration of benzyl starch ether and alkyl polyglycoside in pretreatment fluid,rotation speed and shearing time on the stability of emulsion were studied by measuring oil droplet diameter distribution and using the orthogonal experimental design. The results demonstrate that benzyl starch ether compared with pristine starch has absorption peak of benzyl carboxymethyl. High stable emulsions can be prepared with benzyl starch ether and alkyl polyglycoside complex in 3:2 molar ratio as emulsifier and 9% methyl oleate as solvent. The mean droplet diameter of emulsions is about 1.02 μm and is increased by only 0.1~0.6 μm after storing at 25℃ for 6 months or at(54 ± 2)℃ for 14 days and the water separating proportion is only 2.7%. Cyhalofop-butyl oil-in-water emulsion prepared with benzyl starch ether,alkyl polyglycoside and methyl oleate has a better stability than the conventional emulsions.The results of this study show that benzyl starch compounding with alkyl polyglycosid and methyl oleate can be used as an alternative emulsifier and solvent for the environmentally friendly oil-in-water emulsion formulations.
To replace the common emulsifiers and solvents,the mix-emulsifier of benzyl starch ether in combination with alkyl polyglycoside and solvent of methyl oleate were used in preparation of 10% cyhalofopbutyl aqueous emulsions. The structure of benzyl starch ether was characterized by FTIR and UV spectroscopies in case of benzyl carboxymethy. The effects of different processing parameters,including the concentration of benzyl starch ether and alkyl polyglycoside in pretreatment fluid,rotation speed and shearing time on the stability of emulsion were studied by measuring oil droplet diameter distribution and using the orthogonal experimental design. The results demonstrate that benzyl starch ether compared with pristine starch has absorption peak of benzyl carboxymethyl. High stable emulsions can be prepared with benzyl starch ether and alkyl polyglycoside complex in 3:2 molar ratio as emulsifier and 9% methyl oleate as solvent. The mean droplet diameter of emulsions is about 1.02 μm and is increased by only 0.1~0.6 μm after storing at 25℃ for 6 months or at(54 ± 2)℃ for 14 days and the water separating proportion is only 2.7%. Cyhalofop-butyl oil-in-water emulsion prepared with benzyl starch ether,alkyl polyglycoside and methyl oleate has a better stability than the conventional emulsions.The results of this study show that benzyl starch compounding with alkyl polyglycosid and methyl oleate can be used as an alternative emulsifier and solvent for the environmentally friendly oil-in-water emulsion formulations.
2013, 30(9): 1054-1059
doi: 10.3724/SP.J.1095.2013.20545
Abstract:
The interaction between an anionic dye,C.I. direct blue 199(DB199) and cetyltrimethyl ammonium chloride(CTAC) was investigated by conductivity testing and spectrophotometry. The experimental results revealed that when the concentration of CTAC was less than the critical miscelle concentration(CMC),the conductivity curve of the mixed solution is basically consistent with the theoretical values. When the concentration of CATC was higher than the CMC,approximately 80.88% of the Cl-was adsorbed on the surface of micelles,and it would can drop to 78.48% when dyes were added into the solution. The CTAC surfactant would can cause a hypochromic shift of the maximum absorption wavelength firstly and red-shift with the increase of surfactant concentration. As the surfactant concentration increases,the absorption intensity is first decreased and then increased.
The interaction between an anionic dye,C.I. direct blue 199(DB199) and cetyltrimethyl ammonium chloride(CTAC) was investigated by conductivity testing and spectrophotometry. The experimental results revealed that when the concentration of CTAC was less than the critical miscelle concentration(CMC),the conductivity curve of the mixed solution is basically consistent with the theoretical values. When the concentration of CATC was higher than the CMC,approximately 80.88% of the Cl-was adsorbed on the surface of micelles,and it would can drop to 78.48% when dyes were added into the solution. The CTAC surfactant would can cause a hypochromic shift of the maximum absorption wavelength firstly and red-shift with the increase of surfactant concentration. As the surfactant concentration increases,the absorption intensity is first decreased and then increased.
2013, 30(9): 1060-1064
doi: 10.3724/SP.J.1095.2013.20494
Abstract:
Polyaniline doped with hydrochloric acid was prepared by chemical polymerization,and polyaniline/polysulfone composite film electrode was obtained by mixing the doped polyaniline with the polysulfone solution,and quantitatively adding the mixture to the glassy carbon electrode. The morphology and structure of polyaniline were characterized by scanning electron microscopy(SEM),Fourier transform infrared spectroscopy(FTIR) and X-ray diffraction(XRD). The electrochemical properties of supercapacitor were investigated by cyclic voltammetry, galvanostatic charging-discharging and electrochemical impedance spectroscopy. These results show that polyaniline/polysulfone composite with porous structure has good capacitance performance,and a specific capacitance of 497 F/g is obtained. The composite also exhibits lower inter resistance and good cycle stability.
Polyaniline doped with hydrochloric acid was prepared by chemical polymerization,and polyaniline/polysulfone composite film electrode was obtained by mixing the doped polyaniline with the polysulfone solution,and quantitatively adding the mixture to the glassy carbon electrode. The morphology and structure of polyaniline were characterized by scanning electron microscopy(SEM),Fourier transform infrared spectroscopy(FTIR) and X-ray diffraction(XRD). The electrochemical properties of supercapacitor were investigated by cyclic voltammetry, galvanostatic charging-discharging and electrochemical impedance spectroscopy. These results show that polyaniline/polysulfone composite with porous structure has good capacitance performance,and a specific capacitance of 497 F/g is obtained. The composite also exhibits lower inter resistance and good cycle stability.
2013, 30(9): 1065-1072
doi: 10.3724/SP.J.1095.2013.30175
Abstract:
In this paper,the acid-functionalized multi-wall carbon nanotubes/porous carbon (AMWCNTs/PC) composites were prepared by an effective method,and the application of the composites for electrochemical energy storage was also studied. In the synthesis,the AMWCNTs were mixed with cyclodextrin by a milling method. The acid treatment was favorable for the formation of a uniform and effective composite due to the enhancement of the interaction of AMWCNTs with cyclodextrin. After carbonization under N2 protection and activation with ZnCl2,the AMWCNTs/PC composites could be obtained. The materials were characterized by transmission electron microscopy,X-ray diffraction and Raman spectroscopy. The results indicate that the CNTs are uniformly distributed into the framework of the porous carbon,and the materials have a high BET specific surface area and good conductivity. Cyclic voltammetry(CV) and galvanostatic charge-discharge(GCD) measurements indicate that the composites have good performances for electrochemical energy storage and a high stability. The AMWCNTs/PC-12-4(numbers 12 and 4 represent the mass ratios of cyclodextrin to AMWCNTs and AMWCNTs/PC to ZnCl2,respectively) exhibits a high specific capacitance of 156 F/g,much higher than the AMWCNTs(43 F/g) and PC-4(87 F/g) at 0.5 A/g. Also,the AMWCNTs/PC-12-4 shows superior cycle durability and columbic efficiency over 99.9% after 5000 cycles in KOH,indicating a promising potential for AMWCNTs/PC-12-4 to be used as electrodes materials in supercapacitor.
In this paper,the acid-functionalized multi-wall carbon nanotubes/porous carbon (AMWCNTs/PC) composites were prepared by an effective method,and the application of the composites for electrochemical energy storage was also studied. In the synthesis,the AMWCNTs were mixed with cyclodextrin by a milling method. The acid treatment was favorable for the formation of a uniform and effective composite due to the enhancement of the interaction of AMWCNTs with cyclodextrin. After carbonization under N2 protection and activation with ZnCl2,the AMWCNTs/PC composites could be obtained. The materials were characterized by transmission electron microscopy,X-ray diffraction and Raman spectroscopy. The results indicate that the CNTs are uniformly distributed into the framework of the porous carbon,and the materials have a high BET specific surface area and good conductivity. Cyclic voltammetry(CV) and galvanostatic charge-discharge(GCD) measurements indicate that the composites have good performances for electrochemical energy storage and a high stability. The AMWCNTs/PC-12-4(numbers 12 and 4 represent the mass ratios of cyclodextrin to AMWCNTs and AMWCNTs/PC to ZnCl2,respectively) exhibits a high specific capacitance of 156 F/g,much higher than the AMWCNTs(43 F/g) and PC-4(87 F/g) at 0.5 A/g. Also,the AMWCNTs/PC-12-4 shows superior cycle durability and columbic efficiency over 99.9% after 5000 cycles in KOH,indicating a promising potential for AMWCNTs/PC-12-4 to be used as electrodes materials in supercapacitor.
2013, 30(9): 1073-1081
doi: 10.3724/SP.J.1095.2013.20500
Abstract:
Rates of each procedure composed of catalytic oxygen reduction reaction cycle with free multicopper oxidase as electro-catalyst in the presence of diffusional electron relay were determined by the spectroscopy,Clark-type oxygen electrode and cyclic voltammetry combined with rotating disc electrode technique,respectively. These rates were then compared to verify the rate-determining step in the catalytic reaction.Results from experiments indicate that the fastest step is the internal electron transfer in enzyme molecule(103/s) followed by the enzymatic catalysis of oxygen transformation into water(91/s). The third procedure as for the rate was attributed to the electrochemical reduction reaction of the oxidation product of enzymatic catalytic reaction for electron mediator(0.19/s or 7.8 × 10-3 cm/s) at the surface of base electrode. Mass transfer coefficients of the substrate,oxygen molecule,and oxidized/reduced electron mediator,2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) diammonium(ABTS),were evaluated to be 1.7 × 10-3 cm/s,4.4 × 10-4 cm/s and 6.3 × 10-4cm/s,respectively. Accordingly,chemical reaction rate in the enzyme catalytic electron mediator oxidation was determined to be 0.047/s. So it is apparent that the key procedure of the whole enzymatic catalysis cycle should be ascribed to the enzyme catalytic oxidation of electron mediator and the mass transfer of electron relay. The influence of parameters (including sorts of enzyme,specific activity of enzyme,enzyme concentration,types of mediators and their contents,temperature and pH value of electrolyte,etc.) on the enzyme electro-catalyzed oxygen reduction performance was investigated according to systematic modulation of those parameters. The results confirmed the above conclusions from the kinetic analysis.
Rates of each procedure composed of catalytic oxygen reduction reaction cycle with free multicopper oxidase as electro-catalyst in the presence of diffusional electron relay were determined by the spectroscopy,Clark-type oxygen electrode and cyclic voltammetry combined with rotating disc electrode technique,respectively. These rates were then compared to verify the rate-determining step in the catalytic reaction.Results from experiments indicate that the fastest step is the internal electron transfer in enzyme molecule(103/s) followed by the enzymatic catalysis of oxygen transformation into water(91/s). The third procedure as for the rate was attributed to the electrochemical reduction reaction of the oxidation product of enzymatic catalytic reaction for electron mediator(0.19/s or 7.8 × 10-3 cm/s) at the surface of base electrode. Mass transfer coefficients of the substrate,oxygen molecule,and oxidized/reduced electron mediator,2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) diammonium(ABTS),were evaluated to be 1.7 × 10-3 cm/s,4.4 × 10-4 cm/s and 6.3 × 10-4cm/s,respectively. Accordingly,chemical reaction rate in the enzyme catalytic electron mediator oxidation was determined to be 0.047/s. So it is apparent that the key procedure of the whole enzymatic catalysis cycle should be ascribed to the enzyme catalytic oxidation of electron mediator and the mass transfer of electron relay. The influence of parameters (including sorts of enzyme,specific activity of enzyme,enzyme concentration,types of mediators and their contents,temperature and pH value of electrolyte,etc.) on the enzyme electro-catalyzed oxygen reduction performance was investigated according to systematic modulation of those parameters. The results confirmed the above conclusions from the kinetic analysis.
2013, 30(9): 1082-1088
doi: 10.3724/SP.J.1095.2013.20549
Abstract:
A simple electrochemical sensor was developed for detecting methyl parathion(MP) based on electropolymerization of L-glutamic acid on the glassy carbon electrode. The redox behavior of MP on the sensor was investigated by cyclic voltammetry, and the determination of methyl parathion was performed with differential pulse voltammertry. A highly linear current response to methyl parathion was obtained in the concentration range from 5.0 × 10-7 to 7.5 × 10-4mol/L. A detection limit of 1.0 × 10-9mol/L at a signal-to-noise ratio of 3 was attained. The method could be applied to the determination of methyl parathion in real samples.
A simple electrochemical sensor was developed for detecting methyl parathion(MP) based on electropolymerization of L-glutamic acid on the glassy carbon electrode. The redox behavior of MP on the sensor was investigated by cyclic voltammetry, and the determination of methyl parathion was performed with differential pulse voltammertry. A highly linear current response to methyl parathion was obtained in the concentration range from 5.0 × 10-7 to 7.5 × 10-4mol/L. A detection limit of 1.0 × 10-9mol/L at a signal-to-noise ratio of 3 was attained. The method could be applied to the determination of methyl parathion in real samples.
2013, 30(9): 1089-1095
doi: 10.3724/SP.J.1095.2013.20528
Abstract:
High performance liquid chromatography(HPLC) was used for simultaneous detecting acrylic acid,methacrylic acid and p-toluenesulfonic acid in petrochemical wastewater. The pH of the water sample was adjusted to 1.6,and then solution was filtered with 0.45 μm cellulose acetate membrane before chromatographic analysis. The optimized chromatographic conditions are as follows:phosphate buffer solution(pH=3.0)/acetonitrile(volume ratio is 93:7) as the mobile phase,flow rate=1.0 mL/min,ZORBAX-SB-C18 column,temperature=30℃,MWD detector with detection wavelength at 195 nm,and the injection volume of 10 μL. Under the optimal conditions,the detection limit of acrylic acid,p-toluenesulfonic acid and methacrylic acid is 0.030,0.028 and 0.050 mg/L,respectively. The relative standard deviations of the samples are 1.83%,0.69% and 0.84%,respectively,while the recoveries are in the range from 96% to 112%.
High performance liquid chromatography(HPLC) was used for simultaneous detecting acrylic acid,methacrylic acid and p-toluenesulfonic acid in petrochemical wastewater. The pH of the water sample was adjusted to 1.6,and then solution was filtered with 0.45 μm cellulose acetate membrane before chromatographic analysis. The optimized chromatographic conditions are as follows:phosphate buffer solution(pH=3.0)/acetonitrile(volume ratio is 93:7) as the mobile phase,flow rate=1.0 mL/min,ZORBAX-SB-C18 column,temperature=30℃,MWD detector with detection wavelength at 195 nm,and the injection volume of 10 μL. Under the optimal conditions,the detection limit of acrylic acid,p-toluenesulfonic acid and methacrylic acid is 0.030,0.028 and 0.050 mg/L,respectively. The relative standard deviations of the samples are 1.83%,0.69% and 0.84%,respectively,while the recoveries are in the range from 96% to 112%.
2013, 30(9): 1096-1098
doi: 10.3724/SP.J.1095.2013.30012
Abstract:
Interactions of mandelic acid(MA) and bovine/goat serum albumins(BSA/GSA) have been investigated by FIA-QCM and UV-Vis spectroscopy, respectively. Based on frequency shift of quartz crystal,surface concentrations of immobilized BSA and GSA were 4.9 × 10-12 and 8.8 × 10-12 mol/cm2,respectively. After injecting mandelic acid into FIA-QCM system,frequency of the quartz crystal decreases due to interactions between enantiomers and SA molecules and the shifts between SA and R-MA are greater than those with S-enantiomer,indicating that the interactions of SA molecules with R-MA are stronger than those with S-MA. The UV binding constants for SA with S-MA are smaller than those with R-enantiomer. Taking into account the discrimination factors (αQCM and αUV),GSA shows a better chiral recognition with mandelic acid than BSA.
Interactions of mandelic acid(MA) and bovine/goat serum albumins(BSA/GSA) have been investigated by FIA-QCM and UV-Vis spectroscopy, respectively. Based on frequency shift of quartz crystal,surface concentrations of immobilized BSA and GSA were 4.9 × 10-12 and 8.8 × 10-12 mol/cm2,respectively. After injecting mandelic acid into FIA-QCM system,frequency of the quartz crystal decreases due to interactions between enantiomers and SA molecules and the shifts between SA and R-MA are greater than those with S-enantiomer,indicating that the interactions of SA molecules with R-MA are stronger than those with S-MA. The UV binding constants for SA with S-MA are smaller than those with R-enantiomer. Taking into account the discrimination factors (αQCM and αUV),GSA shows a better chiral recognition with mandelic acid than BSA.
