The sensitivity and the recovery behavior of SnO_2-based gas sensor prepared from a commercial SnO_2 powder were tested under the low concentration of DMMP(0.5μg/g) in the flow system at 350℃.In order to improve the...The sensitivity and the recovery behavior of SnO_2-based gas sensor prepared from a commercial SnO_2 powder were tested under the low concentration of DMMP(0.5μg/g) in the flow system at 350℃.In order to improve the sensitivity of the sensor,promoters such as NiO,Nb_2O_5,MoO_3,and Sb_2O_3 were added into SnO_2 powder.The sensitivities were increased up to 80% from 50% but they were not recovered.Only the SnO2-based gas sensor promoted with MoO_3 and Sb_2O_3 was recovered after detection of DMMP,although the recovery rate was slow.In particular,the SnO_2-based sensor promoted with 5wt% of MoO_3 and 1wt% of Sb_2O_3 simultaneously showed an complete recovery ability,though its sensitivity was 40% which was lower than that of SnO_2 gas sensor without promoters.This ability was discussed in terms of catalytic roles of promoters.展开更多
Thermodynamic assessment in the ternary systems ZrO2 -CeO2 -Y2 O3, ZrO2 -CeO2 -Ce2 03 and the limiting binaries ZrO2 -Y2 O3, ZrO2 -CeO2, CeO2 -Y2 03, ZrO2 -Ce2O3, CeO2 -Ce2O3 as well as the modeling for oxides are rev...Thermodynamic assessment in the ternary systems ZrO2 -CeO2 -Y2 O3, ZrO2 -CeO2 -Ce2 03 and the limiting binaries ZrO2 -Y2 O3, ZrO2 -CeO2, CeO2 -Y2 03, ZrO2 -Ce2O3, CeO2 -Ce2O3 as well as the modeling for oxides are reviewed comprehensively. Based on the recent estimations on the YO1.5-CeO2, ZrO2-CeO2 and ZrO2 -YO1.6 systems, isothermal sections at 1273 and 1 973 K of the ternary CeO2- ZrO2-YO1.5system are calculated. In the system of ZrO2-CeO2-Ce2O3, the complex relation between the nonstoichiometry （y） in CeO2-x, the composition of the ZrO2 -CeO2 solid solution and the oxygen partial pressure （Po2 ） for different ZrO2 containing solid solutions CexZr1-xO2-x. are evaluated from 1 473 to 1 773 K. The relation between the degree of Ce^＋4 reduction to Ce.3 under different Po2 in the fluorite CeO2-xy and CexZr1-xOz-x solid solutions at different temperatures can be used as a guide in the development of functional ceramics.展开更多
The Li_(4+x)Al_xSi_(1-x)O_(4-y)Al_2O_3 (x = 0 to 0.5, y = 0 to 0.5) ionconductors were prepared by the Sol-Gel method and examined in detail. The powder and sinteredsamples were characterized by TG-DTA, XRD, SEM, and ...The Li_(4+x)Al_xSi_(1-x)O_(4-y)Al_2O_3 (x = 0 to 0.5, y = 0 to 0.5) ionconductors were prepared by the Sol-Gel method and examined in detail. The powder and sinteredsamples were characterized by TG-DTA, XRD, SEM, and AC impedance techniques. The experimentalresults show that the conductivity and sinterability increase with the amount of excess Al_2O_3 inthe silicate. The particle size of the powder samples is about 0.13 μm. The maximum conductivity at18 ℃ is 3.057 * 10^(-5) s/cm for Li_(4.4)Al_(0.4)Si_(0.6)O_4-0.3 Al_2O_3.展开更多
文摘The sensitivity and the recovery behavior of SnO_2-based gas sensor prepared from a commercial SnO_2 powder were tested under the low concentration of DMMP(0.5μg/g) in the flow system at 350℃.In order to improve the sensitivity of the sensor,promoters such as NiO,Nb_2O_5,MoO_3,and Sb_2O_3 were added into SnO_2 powder.The sensitivities were increased up to 80% from 50% but they were not recovered.Only the SnO2-based gas sensor promoted with MoO_3 and Sb_2O_3 was recovered after detection of DMMP,although the recovery rate was slow.In particular,the SnO_2-based sensor promoted with 5wt% of MoO_3 and 1wt% of Sb_2O_3 simultaneously showed an complete recovery ability,though its sensitivity was 40% which was lower than that of SnO_2 gas sensor without promoters.This ability was discussed in terms of catalytic roles of promoters.
基金Postdoctoral Science Foundation of China(2012M520605)Research Foundation of Taiyuan University of Technology(tyut-rc201369a,2013Z040)+1 种基金Open Foundation of State Key Laboratory of Coal Conversion(09-102)Natural Science Foundation of Shanxi Province(2013011042-1)
文摘Thermodynamic assessment in the ternary systems ZrO2 -CeO2 -Y2 O3, ZrO2 -CeO2 -Ce2 03 and the limiting binaries ZrO2 -Y2 O3, ZrO2 -CeO2, CeO2 -Y2 03, ZrO2 -Ce2O3, CeO2 -Ce2O3 as well as the modeling for oxides are reviewed comprehensively. Based on the recent estimations on the YO1.5-CeO2, ZrO2-CeO2 and ZrO2 -YO1.6 systems, isothermal sections at 1273 and 1 973 K of the ternary CeO2- ZrO2-YO1.5system are calculated. In the system of ZrO2-CeO2-Ce2O3, the complex relation between the nonstoichiometry （y） in CeO2-x, the composition of the ZrO2 -CeO2 solid solution and the oxygen partial pressure （Po2 ） for different ZrO2 containing solid solutions CexZr1-xO2-x. are evaluated from 1 473 to 1 773 K. The relation between the degree of Ce^＋4 reduction to Ce.3 under different Po2 in the fluorite CeO2-xy and CexZr1-xOz-x solid solutions at different temperatures can be used as a guide in the development of functional ceramics.
基金theNaturalScienceFoundationofHebeiProvince (No .2 96 16 9)
文摘The Li_(4+x)Al_xSi_(1-x)O_(4-y)Al_2O_3 (x = 0 to 0.5, y = 0 to 0.5) ionconductors were prepared by the Sol-Gel method and examined in detail. The powder and sinteredsamples were characterized by TG-DTA, XRD, SEM, and AC impedance techniques. The experimentalresults show that the conductivity and sinterability increase with the amount of excess Al_2O_3 inthe silicate. The particle size of the powder samples is about 0.13 μm. The maximum conductivity at18 ℃ is 3.057 * 10^(-5) s/cm for Li_(4.4)Al_(0.4)Si_(0.6)O_4-0.3 Al_2O_3.
