Single-crystalline ZnO nanowire arrays with different aspect ratios and nanowire densities were prepared by the hydrothermal growing method using polyethyleneimine (PEI) as a surfactant. PEI can only hinder the late...Single-crystalline ZnO nanowire arrays with different aspect ratios and nanowire densities were prepared by the hydrothermal growing method using polyethyleneimine (PEI) as a surfactant. PEI can only hinder the lateral growth of the ZnO nanowires, which is observed by high resolution transmission electron microscopy (HRTEM) analysis. Dye-sensitized solar cells were assembled by the ZnO nanowire arrays with different thicknesses, which can be controlled by the growing time and characterized using photocurrent-voltage measurements. Their photocurrent densities and energy allover conversion efficiencies increased with increasing ZnO nanowire lengths. Short-circuit current density of 4.31 mA.cm-2 and allover energy conversion efficiency of 0.87% were achieved with 12.9-μm-long ZnO nanowire arrays.展开更多
The nanocrystalline Bi2O3-Y2O3 solid electrolyte material was synthesized by pressureless reactive sintering process with Bi2O3 and Y2O3 nano mixed powder as raw materials, which was prepared by a chemical coprecipita...The nanocrystalline Bi2O3-Y2O3 solid electrolyte material was synthesized by pressureless reactive sintering process with Bi2O3 and Y2O3 nano mixed powder as raw materials, which was prepared by a chemical coprecipitation process. The study on the behavior of nano δ-Bi2O3 formation and its grain growth showed that the solid solution reaction of Y2O3 and δ-Bi2O3 to form δ-Bi2O3 occurs mainly in the initial stage of sintering process, and nano δ-Bi2O3 crystal grains grow approximately following the rule of paracurve ((D-D0)^2=K.t) during sintering process. After sintered at 600℃ for 2 h, the samples could reach above 96% in relative density and have dense microstructure with few remaining pores, the δ-Bi2O3 grains are less than 100 nm in size.展开更多
By using micron α-SisN4, SiO2, Al2O3 and h-BN as starting materials, O' -SiAION-BN ( Si2-z AlzO1 +z N2-z, z= 0. 3) composite was synthesized by reaction sintering. According to theoretical proportion ratio: n( ...By using micron α-SisN4, SiO2, Al2O3 and h-BN as starting materials, O' -SiAION-BN ( Si2-z AlzO1 +z N2-z, z= 0. 3) composite was synthesized by reaction sintering. According to theoretical proportion ratio: n( SiO2)/n( α-Si3N4) = 1, the effects of two sintering aid composites, Y2O3 + B2O3 and Y2O3 + TiO2 at 1700℃ for 2h, were studied. The results indicate that Y2 O3 + TiO2 as sintering aid can accelerate reaction sintering of O' -SiAION-BN more effectively than Y2O3 + B2O3, and the relative density of the composites declined with the increase of BN addition (10%, 20% and 30% respectively); XRD analysis found that excessive β-Si3N4 existed in the O' -SiAION-BN composite. Therefore, in order to get more pure O' -SiAION and BN phases in the composites ore SiO2 is needed. When Y2O3 + TiO2 was used as sintering aid and addition of BN was 10%, the result of cross experiment on condition of A- n(SiO2)/n(α-Si3N4) was 1.05, 1.1 and 1.2; B-- addition of sintering aid was 2%, 4% and 6% ; C-- firing temperature was 1600℃, 1650℃ and 1700℃ ; D--soaking time was 1h, 2h and 3h, shows that the sintering properties were influenced by factors of firing temperature, soaking time, addition of sintering aid and n( SiO2 )/n(α-SisN4) in order of importance. In addition, the technical parameter A s B 3 C s D3 can achieve the highest relative density. Besides, using Pattern Recognition method, the optimized parameter range to form pure O' -SiAION and BN without β-Si3N4 remained was determined as Y 〉 1024X^2 - 230. 400X + 11.088 ( X = 0. 9999A -0. 0006C - 0. 0163D, Y = 0. 0163A + 0. 009B -0. 0014C +0. 9999D).展开更多
Single-crystalline anatase TiO2nanorods have been prepared by solvothermal method using tetrabutylammonium hydroxide(TBAH) as a morphology controlling agent.The obtained TiO2nanorods are dominated by a large percent...Single-crystalline anatase TiO2nanorods have been prepared by solvothermal method using tetrabutylammonium hydroxide(TBAH) as a morphology controlling agent.The obtained TiO2nanorods are dominated by a large percentage of {010} facets.The power conversion efficiency of dye-sensitized solar cell(DSSC) based on anatase TiO2nanorods(8.66%) exhibits a significant improvement(35%) compared to that of P25 TiO2(5.66%).The high performance of the anatase TiO2nanorods solar cell is ascribed to their large percent of exposed {010} facets as well as balancing their surface areas and sizes.展开更多
A series of zinc oxide(ZnO)nanorods arrays with different morphologies are synthesized on stainless steel mesh via a facile electrodeposition method.The influences of electrodeposition parameters on the diameter,lengt...A series of zinc oxide(ZnO)nanorods arrays with different morphologies are synthesized on stainless steel mesh via a facile electrodeposition method.The influences of electrodeposition parameters on the diameter,length,density and morphology of obtained ZnO nanorods are investigated systematically.The results indicate that the electrodeposition potential is the key factor for the morphology of the obtained ZnO nanorods,which further showed the effect on the photocatalytic property of the obtained samples.Meanwhile,the prepared ZnO nanorods array exhibits an excellent photocatalytic activity for methylene blue(MB)in ultraviolet light.The degradation efficiency for MB solution reaches 95.1%under the irradiation of ultraviolet light for 120 min.In addition,the photocatalytic property of the prepared ZnO nanorods can be extended to the visible light region after the modified with graphene oxide(GO).The obtained GO/ZnO composite also shows remarkable photocatalytic activity and photostability.The photodegradation efficiency for MB is 83.6%,and the catalytic performance retains 97.3% of its initial photocatalytic activity after five cycles.展开更多
A novel route to comprehensive utilization of valuable elements such as Ti, A1, Si and Mg in Ti-bearing electric arc furnace molten slag (Ti-bearing EAF slag) was proposed. The route can be expressed as a three-step...A novel route to comprehensive utilization of valuable elements such as Ti, A1, Si and Mg in Ti-bearing electric arc furnace molten slag (Ti-bearing EAF slag) was proposed. The route can be expressed as a three-step process including alkali fusion, water leaching and acidolysis. Following these processes under the optimum conditions, the recovery ratios of TiO2, Al2O3, SiO2 and MgO were about 97.5, 93.5, 27.9 and 53.5%, respectively. Meanwhile, nanostructured TiO2, NaA zeolite and Mg(OH)2 fire retardant were synthesized simultaneously by using Ti-bearing EAF slag as raw materials. In addition, the photocatalytic activity of prepared nanostructured TiO2 and the adsorption property of obtained NaA zeolite were investigated. The results showed that the photodegradation efficiency of as-prepared TiO2 was 80% for rhodamine B and the adsorption efficiency of NaA zeolite was 61% for Cu2+ under the optimum conditions.展开更多
基金financially supported by the National Science Foundation of China (Nos.10775096 and 51072112)China Postdoctoral Science Foundation (No.20100480579)+4 种基金Key Subject of Shanghai Municipal Education Commission (No.J50102)Special Research Foundation for Training and Selecting Outstanding Young Teachers of Universities in ShanghaiInnovation Foundation of Shanghai UniversityNature Science Foundation of Shanghai (No.06ZR14035)Shanghai Leading Academic Disciplines (No.T0101)
文摘Single-crystalline ZnO nanowire arrays with different aspect ratios and nanowire densities were prepared by the hydrothermal growing method using polyethyleneimine (PEI) as a surfactant. PEI can only hinder the lateral growth of the ZnO nanowires, which is observed by high resolution transmission electron microscopy (HRTEM) analysis. Dye-sensitized solar cells were assembled by the ZnO nanowire arrays with different thicknesses, which can be controlled by the growing time and characterized using photocurrent-voltage measurements. Their photocurrent densities and energy allover conversion efficiencies increased with increasing ZnO nanowire lengths. Short-circuit current density of 4.31 mA.cm-2 and allover energy conversion efficiency of 0.87% were achieved with 12.9-μm-long ZnO nanowire arrays.
基金financially supported by the National Nature Science Foundation of China (No.20101006)the Nano Technology Special Foundation of Shanghai Science and Technology Committee (No.O452nm073)
文摘The nanocrystalline Bi2O3-Y2O3 solid electrolyte material was synthesized by pressureless reactive sintering process with Bi2O3 and Y2O3 nano mixed powder as raw materials, which was prepared by a chemical coprecipitation process. The study on the behavior of nano δ-Bi2O3 formation and its grain growth showed that the solid solution reaction of Y2O3 and δ-Bi2O3 to form δ-Bi2O3 occurs mainly in the initial stage of sintering process, and nano δ-Bi2O3 crystal grains grow approximately following the rule of paracurve ((D-D0)^2=K.t) during sintering process. After sintered at 600℃ for 2 h, the samples could reach above 96% in relative density and have dense microstructure with few remaining pores, the δ-Bi2O3 grains are less than 100 nm in size.
文摘By using micron α-SisN4, SiO2, Al2O3 and h-BN as starting materials, O' -SiAION-BN ( Si2-z AlzO1 +z N2-z, z= 0. 3) composite was synthesized by reaction sintering. According to theoretical proportion ratio: n( SiO2)/n( α-Si3N4) = 1, the effects of two sintering aid composites, Y2O3 + B2O3 and Y2O3 + TiO2 at 1700℃ for 2h, were studied. The results indicate that Y2 O3 + TiO2 as sintering aid can accelerate reaction sintering of O' -SiAION-BN more effectively than Y2O3 + B2O3, and the relative density of the composites declined with the increase of BN addition (10%, 20% and 30% respectively); XRD analysis found that excessive β-Si3N4 existed in the O' -SiAION-BN composite. Therefore, in order to get more pure O' -SiAION and BN phases in the composites ore SiO2 is needed. When Y2O3 + TiO2 was used as sintering aid and addition of BN was 10%, the result of cross experiment on condition of A- n(SiO2)/n(α-Si3N4) was 1.05, 1.1 and 1.2; B-- addition of sintering aid was 2%, 4% and 6% ; C-- firing temperature was 1600℃, 1650℃ and 1700℃ ; D--soaking time was 1h, 2h and 3h, shows that the sintering properties were influenced by factors of firing temperature, soaking time, addition of sintering aid and n( SiO2 )/n(α-SisN4) in order of importance. In addition, the technical parameter A s B 3 C s D3 can achieve the highest relative density. Besides, using Pattern Recognition method, the optimized parameter range to form pure O' -SiAION and BN without β-Si3N4 remained was determined as Y 〉 1024X^2 - 230. 400X + 11.088 ( X = 0. 9999A -0. 0006C - 0. 0163D, Y = 0. 0163A + 0. 009B -0. 0014C +0. 9999D).
基金the financial support of the project from the National Natural Science Foundation of China(No.51202139)the Specialized Research Fund for the Doctoral Program of Higher education(No.20123108120022)+2 种基金the Natural Science Foundation of Shanghai(Nos. 12ZR1443900 and 14ZR1416400)the Special Research Foundation for Training and Selecting Outstanding Young Teachers of Universities in Shanghai(No.ZZSD12041)the Innovation Foundation of Shanghai University
文摘Single-crystalline anatase TiO2nanorods have been prepared by solvothermal method using tetrabutylammonium hydroxide(TBAH) as a morphology controlling agent.The obtained TiO2nanorods are dominated by a large percentage of {010} facets.The power conversion efficiency of dye-sensitized solar cell(DSSC) based on anatase TiO2nanorods(8.66%) exhibits a significant improvement(35%) compared to that of P25 TiO2(5.66%).The high performance of the anatase TiO2nanorods solar cell is ascribed to their large percent of exposed {010} facets as well as balancing their surface areas and sizes.
基金supported by the National Natural Science Foundation of China(Nos.51774217,51604202 and 51604201)the Shanghai Sailing Program(No.19YF1415800)the Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education,China(No.FMRU-lab-20-2).
文摘A series of zinc oxide(ZnO)nanorods arrays with different morphologies are synthesized on stainless steel mesh via a facile electrodeposition method.The influences of electrodeposition parameters on the diameter,length,density and morphology of obtained ZnO nanorods are investigated systematically.The results indicate that the electrodeposition potential is the key factor for the morphology of the obtained ZnO nanorods,which further showed the effect on the photocatalytic property of the obtained samples.Meanwhile,the prepared ZnO nanorods array exhibits an excellent photocatalytic activity for methylene blue(MB)in ultraviolet light.The degradation efficiency for MB solution reaches 95.1%under the irradiation of ultraviolet light for 120 min.In addition,the photocatalytic property of the prepared ZnO nanorods can be extended to the visible light region after the modified with graphene oxide(GO).The obtained GO/ZnO composite also shows remarkable photocatalytic activity and photostability.The photodegradation efficiency for MB is 83.6%,and the catalytic performance retains 97.3% of its initial photocatalytic activity after five cycles.
基金This study was supported by the National Natural Science Foundation of China (Nos. 51471122 and 51604202), the China Postdoctoral Science Foundation (No. 2016M592397) and the Science and Technology Project of Guangdong Province (No. 2013B090600025).
文摘A novel route to comprehensive utilization of valuable elements such as Ti, A1, Si and Mg in Ti-bearing electric arc furnace molten slag (Ti-bearing EAF slag) was proposed. The route can be expressed as a three-step process including alkali fusion, water leaching and acidolysis. Following these processes under the optimum conditions, the recovery ratios of TiO2, Al2O3, SiO2 and MgO were about 97.5, 93.5, 27.9 and 53.5%, respectively. Meanwhile, nanostructured TiO2, NaA zeolite and Mg(OH)2 fire retardant were synthesized simultaneously by using Ti-bearing EAF slag as raw materials. In addition, the photocatalytic activity of prepared nanostructured TiO2 and the adsorption property of obtained NaA zeolite were investigated. The results showed that the photodegradation efficiency of as-prepared TiO2 was 80% for rhodamine B and the adsorption efficiency of NaA zeolite was 61% for Cu2+ under the optimum conditions.