Materials Lao.8Sro.2Gao.83Mgo.17_xCox03_6 with x = 0, 0.05, 0.085, 0.10, and 0.15 are synthesized by laser rapid solidification. It is shown that the samples prepared by laser rapid solidification give rise to unique ...Materials Lao.8Sro.2Gao.83Mgo.17_xCox03_6 with x = 0, 0.05, 0.085, 0.10, and 0.15 are synthesized by laser rapid solidification. It is shown that the samples prepared by laser rapid solidification give rise to unique spear-like or leaf-like microstructures which are orderly arranged and densely packed. Their electrical properties each show a general depen dence of the Co content and the total conductivities of Lao.8Sro.2Gao.83Mgo.085Coo.08503_6 prepared by laser rapid solidification are measured to be 0.067, 0.124, and 0.202 S.cm-1 at 600, 700, and 800 ℃, respectively, which are much higher than by conventional solid state reactions. Moreover, the electrical conductivities each as a function of the oxy gen partial pressure are also measured. It is shown that the samples with the Co content values 〈 8.5 mol% each exhibit basically ionic conduction while those for Co content values 〉 10 mol % each show ionic mixed electronic conduction under oxygen partial pressures from 10-16 atm （1 atm = 1.01325 x 105 Pa） to 0.98 atm. The improved ionic conductivity of Lao.sSro.2Gao.83Mgo.085Coo.08503 prepared by laser rapid solidification compared with by solid state reactions is attributed to the unique microstructure of the sample generated during laser rapid solidification.展开更多
A mathematical model for the estimation of oxygen-ion conductivity of doped ZrO2 and CeO2 electrolytes was established based on the assumptions that the electronic conduction and defect association can be neglected. A...A mathematical model for the estimation of oxygen-ion conductivity of doped ZrO2 and CeO2 electrolytes was established based on the assumptions that the electronic conduction and defect association can be neglected. A linear regression method was employed to determine the parameters in the model. This model was confirmed by the published conductivity data of the doped ZrO2 and CeO2 electrolytes. In addition, a series of compositions in Ce0.8Gd0.2-xMxO1.9-δsystem (M is the co-dopant) was prepared, their high temperature conductivity were measured. The model was further validated by the measured conductivity data.展开更多
Direct electrochemical extraction of TisSia from pressed cathode pellets comprising of powdered Ti/Si- containing metal oxide compounds was investigated by using molten salt electro-deoxidation technology. Three group...Direct electrochemical extraction of TisSia from pressed cathode pellets comprising of powdered Ti/Si- containing metal oxide compounds was investigated by using molten salt electro-deoxidation technology. Three groups of mixtures including TiO2 mixed with SiO2, Ti-bearing blast furnace slag （TBFS） mixed with TiO2, and TBFS mixed with high-titanium slag （HTS） were prepared at the same stoichiometric ratio （Ti ： Si = 5 ： 3） corresponding to the target composition of Ti5Si3, and used as the starting materials in this experiment, respec- tively. The pressed porous cylindrical pellet of the Ti/Si-contalning compounds served as a cathode, and two different anode systems, i.e., the inert solid oxide oxygen-ion-conducting membrane （SOM） based anode system and graphite-based anode system were used contrastively. The electrochemical experiment was carried out at 900--1050℃ and 3.0--4.0V in molten CaCl2 electrolyte. The results show that the oxide components were electro-deoxidized effectively and Ti5Si3 could be directly extracted from these complex Ti/Si-containing metal oxide compounds.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.10974183)the Fund for Science and Technology Innovation Team of Zhengzhou City,China(Grant No.2011-3)the Postdoctoral Research Sponsorship in Henan Province,China(Grant No.2011002)
文摘Materials Lao.8Sro.2Gao.83Mgo.17_xCox03_6 with x = 0, 0.05, 0.085, 0.10, and 0.15 are synthesized by laser rapid solidification. It is shown that the samples prepared by laser rapid solidification give rise to unique spear-like or leaf-like microstructures which are orderly arranged and densely packed. Their electrical properties each show a general depen dence of the Co content and the total conductivities of Lao.8Sro.2Gao.83Mgo.085Coo.08503_6 prepared by laser rapid solidification are measured to be 0.067, 0.124, and 0.202 S.cm-1 at 600, 700, and 800 ℃, respectively, which are much higher than by conventional solid state reactions. Moreover, the electrical conductivities each as a function of the oxy gen partial pressure are also measured. It is shown that the samples with the Co content values 〈 8.5 mol% each exhibit basically ionic conduction while those for Co content values 〉 10 mol % each show ionic mixed electronic conduction under oxygen partial pressures from 10-16 atm （1 atm = 1.01325 x 105 Pa） to 0.98 atm. The improved ionic conductivity of Lao.sSro.2Gao.83Mgo.085Coo.08503 prepared by laser rapid solidification compared with by solid state reactions is attributed to the unique microstructure of the sample generated during laser rapid solidification.
基金Project(2004ABA078) supported by the Natural Science Foundation of Hubei Province
文摘A mathematical model for the estimation of oxygen-ion conductivity of doped ZrO2 and CeO2 electrolytes was established based on the assumptions that the electronic conduction and defect association can be neglected. A linear regression method was employed to determine the parameters in the model. This model was confirmed by the published conductivity data of the doped ZrO2 and CeO2 electrolytes. In addition, a series of compositions in Ce0.8Gd0.2-xMxO1.9-δsystem (M is the co-dopant) was prepared, their high temperature conductivity were measured. The model was further validated by the measured conductivity data.
基金the National Natural Science Foundation of China(No.51074105)the China Postdoctoral Science Foundation(No.2012M520873)China National Funds for Distinguished Young Scientists (No.51225401)
文摘Direct electrochemical extraction of TisSia from pressed cathode pellets comprising of powdered Ti/Si- containing metal oxide compounds was investigated by using molten salt electro-deoxidation technology. Three groups of mixtures including TiO2 mixed with SiO2, Ti-bearing blast furnace slag （TBFS） mixed with TiO2, and TBFS mixed with high-titanium slag （HTS） were prepared at the same stoichiometric ratio （Ti ： Si = 5 ： 3） corresponding to the target composition of Ti5Si3, and used as the starting materials in this experiment, respec- tively. The pressed porous cylindrical pellet of the Ti/Si-contalning compounds served as a cathode, and two different anode systems, i.e., the inert solid oxide oxygen-ion-conducting membrane （SOM） based anode system and graphite-based anode system were used contrastively. The electrochemical experiment was carried out at 900--1050℃ and 3.0--4.0V in molten CaCl2 electrolyte. The results show that the oxide components were electro-deoxidized effectively and Ti5Si3 could be directly extracted from these complex Ti/Si-containing metal oxide compounds.
