To clarify the effect of SnO2 particle size on the arc erosion behavior of AgSnO2 contact material, Ag?4%SnO2 (mass fraction) contact materials with different sizes of SnO2 particles were fabricated by powder metallur...To clarify the effect of SnO2 particle size on the arc erosion behavior of AgSnO2 contact material, Ag?4%SnO2 (mass fraction) contact materials with different sizes of SnO2 particles were fabricated by powder metallurgy. The microstructure of Ag?4%SnO2 contact materials was characterized, and the relative density, hardness and electrical conductivity were measured. The arc erosion of Ag?4%SnO2 contact materials was tested, the arc duration and mass loss before and after arc erosion were determined, the surface morphologies and compositions of Ag?4%SnO2 contact materials after arc erosion were characterized, and the arc erosion mechanism of AgSnO2 contact materials was discussed. The results show that fine SnO2 particle is beneficial for the improvement of the relative density and hardness, but decreases the electrical conductivity. With the decrease of SnO2 particle size, Ag?4%SnO2contact material presents shorter arc duration, less mass loss, larger erosion area and shallower arc erosion pits.展开更多
Ag SnO_2是一种较为理想的Ag Cd O替代材料,但由于其中SnO_2近乎绝缘,使得触头材料的接触电阻增大,故改善SnO_2的导电性是急需解决的重大难题。采用基于密度泛函理论的第一性原理赝势法,通过建模的方法,分别建立不同比例(50%、25%、16....Ag SnO_2是一种较为理想的Ag Cd O替代材料,但由于其中SnO_2近乎绝缘,使得触头材料的接触电阻增大,故改善SnO_2的导电性是急需解决的重大难题。采用基于密度泛函理论的第一性原理赝势法,通过建模的方法,分别建立不同比例(50%、25%、16.67%、12.5%、8.34%)La掺杂的SnO_2晶胞模型,并计算分析其晶格常数、电荷布居、能带结构和态密度等性质。结果表明,La掺杂后触头材料中的SnO_2仍属于直接带隙半导体材料,但其禁带宽度变小,载流子浓度变大,使得材料的导电性增强。当La掺杂比为16.67%时导电性最佳。展开更多
Service life of two different oxide anodes in phenolsulfonic acid (PSA) solution was investigated by accelerated electrolysis. The durability of Ti/IrO_2+Ta_2 O_5 anode increased by the addition of SnO_2 in the mixed...Service life of two different oxide anodes in phenolsulfonic acid (PSA) solution was investigated by accelerated electrolysis. The durability of Ti/IrO_2+Ta_2 O_5 anode increased by the addition of SnO_2 in the mixed oxides. The degradation mechanisms of Ti/IrO_2+ Ta_2 O_5 and Ti/IrO_2 +Ta_2 O_5 +SnO+2 anodes were different. It was shown from the observation of scanning electron microscopy (SEM) and the electrochcmical measurement that, the deactivation of Ti/IrO_2 + Ta_2 O_5 anode was due to the build-up of an organic film on surface. The growth of the covered film on surface was restricted by addition of SnO_2, which resulted in increasing of the service life of anodes. The over-potential for oxygen evolution on Ti/IrO_2 +Ta_2 O_5 electrode increased after doping SnO_2, and the intermediate products of PSA building-up on the surface was much more rapidly oxidized. Meanwhile, a certain part of the surface oxide deposit entered into the solution leading to loss of oxides, which resulted in degradation of Ti/IroO_2 + Ta_2 O_5 anode containing SnO_2 component.展开更多
Conducting supporters of purified single-walled carbon nanotubes（SWNTs） and graphene oxide（GO）were used to confine pomegranate-structured Sn O2 nanospheres for forming SnO-GO-SWNT composites.As anode material for ...Conducting supporters of purified single-walled carbon nanotubes（SWNTs） and graphene oxide（GO）were used to confine pomegranate-structured Sn O2 nanospheres for forming SnO-GO-SWNT composites.As anode material for lithium ion batteries（LIBs）, this composite exhibits a stable and large reversible capacity together with an excellent rate capability. In addition, an analysis of the AC impedance spectroscopy has been used to confirm the enhanced mechanism for LIB performance. The improved electrochemical performance should be ascribed greatly to the reinforced synergistic effects between GO and SWNT networks, and their enhanced contribution of the conductivity. These results indicate that this composite has potential for utilization in high-rate and durable LIBs.展开更多
SnO2 doped with Y were prepared by co-precipitation method and tested in lithium-ion cells. The structure and morphology of the materials were characterized by X-ray diffraction (XRD) and transmission electron microsc...SnO2 doped with Y were prepared by co-precipitation method and tested in lithium-ion cells. The structure and morphology of the materials were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). XRD patterns presented that the all the as-prepared materials had tetragonal rutile structure but a second phase (Y2O3) was observed when Y content reached 4%. TEM micrograph indicated that Y doped SnO2 had a small particle size ranging from 20 to 25 nm. The electrochemical properties for an anode active material in lithium-ion batteries were investigated at room temperature, including the observed capacity involved in the first-discharge and the reversible capacity values during subsequent charge-discharge cycles. The as-prepared Y-doped SnO2 exhibited promising electrochemical properties as anodes for lithium-ion batteries.展开更多
The acid-proof anode Ti/SnO2+Mn2O3/PbO2 doped with Ce was prepared by thermal decomposition and electrodeposition combination technology, the effect of Ce on the morphology and structure of anode was also studied in t...The acid-proof anode Ti/SnO2+Mn2O3/PbO2 doped with Ce was prepared by thermal decomposition and electrodeposition combination technology, the effect of Ce on the morphology and structure of anode was also studied in this paper. The results obtained by cyclic voltammetry (CV), electrochemical impedance spectroscopic (EIS), X-ray Diffraction (XRD) and scanning electron microscopy (SEM) indicated that PbO2 crystal grains presented honeycomb structure were formed on the electrode surface by doping with Ce. The specific surface areas and catalytic active sites of the Ce-PbO2 doped electrode were increased and the catalytic activity was evidently greater than the undoped one. However, when Ce was doped into the intermediate layer (SnO2+Mn2O3), a more cracked surface structure formed, thus leading electrode deactivation by passivation of the Ti-substrate. So the anodic stability was decreased according to the accelerated life tests.展开更多
基金Project(51274163)supported by the National Natural Science Foundation of ChinaProject(13JS076)supported by the Key Laboratory Research Program of Shaanxi Province,China+1 种基金Project(2012KCT-25)supported by the Pivot Innovation Team of Shaanxi Electrical Materials and Infiltration Technique,ChinaProject(2011HBSZS009)supported by the Special Foundation of Key Disciplines,China
文摘To clarify the effect of SnO2 particle size on the arc erosion behavior of AgSnO2 contact material, Ag?4%SnO2 (mass fraction) contact materials with different sizes of SnO2 particles were fabricated by powder metallurgy. The microstructure of Ag?4%SnO2 contact materials was characterized, and the relative density, hardness and electrical conductivity were measured. The arc erosion of Ag?4%SnO2 contact materials was tested, the arc duration and mass loss before and after arc erosion were determined, the surface morphologies and compositions of Ag?4%SnO2 contact materials after arc erosion were characterized, and the arc erosion mechanism of AgSnO2 contact materials was discussed. The results show that fine SnO2 particle is beneficial for the improvement of the relative density and hardness, but decreases the electrical conductivity. With the decrease of SnO2 particle size, Ag?4%SnO2contact material presents shorter arc duration, less mass loss, larger erosion area and shallower arc erosion pits.
文摘Ag SnO_2是一种较为理想的Ag Cd O替代材料,但由于其中SnO_2近乎绝缘,使得触头材料的接触电阻增大,故改善SnO_2的导电性是急需解决的重大难题。采用基于密度泛函理论的第一性原理赝势法,通过建模的方法,分别建立不同比例(50%、25%、16.67%、12.5%、8.34%)La掺杂的SnO_2晶胞模型,并计算分析其晶格常数、电荷布居、能带结构和态密度等性质。结果表明,La掺杂后触头材料中的SnO_2仍属于直接带隙半导体材料,但其禁带宽度变小,载流子浓度变大,使得材料的导电性增强。当La掺杂比为16.67%时导电性最佳。
文摘Service life of two different oxide anodes in phenolsulfonic acid (PSA) solution was investigated by accelerated electrolysis. The durability of Ti/IrO_2+Ta_2 O_5 anode increased by the addition of SnO_2 in the mixed oxides. The degradation mechanisms of Ti/IrO_2+ Ta_2 O_5 and Ti/IrO_2 +Ta_2 O_5 +SnO+2 anodes were different. It was shown from the observation of scanning electron microscopy (SEM) and the electrochcmical measurement that, the deactivation of Ti/IrO_2 + Ta_2 O_5 anode was due to the build-up of an organic film on surface. The growth of the covered film on surface was restricted by addition of SnO_2, which resulted in increasing of the service life of anodes. The over-potential for oxygen evolution on Ti/IrO_2 +Ta_2 O_5 electrode increased after doping SnO_2, and the intermediate products of PSA building-up on the surface was much more rapidly oxidized. Meanwhile, a certain part of the surface oxide deposit entered into the solution leading to loss of oxides, which resulted in degradation of Ti/IroO_2 + Ta_2 O_5 anode containing SnO_2 component.
基金supported by the Natural Science Foundations of China(No.21203025,51202031,11004032 and 11074039)Funds of Education Committee of Fujian Province(JK2013010 and JA13064)
文摘Conducting supporters of purified single-walled carbon nanotubes（SWNTs） and graphene oxide（GO）were used to confine pomegranate-structured Sn O2 nanospheres for forming SnO-GO-SWNT composites.As anode material for lithium ion batteries（LIBs）, this composite exhibits a stable and large reversible capacity together with an excellent rate capability. In addition, an analysis of the AC impedance spectroscopy has been used to confirm the enhanced mechanism for LIB performance. The improved electrochemical performance should be ascribed greatly to the reinforced synergistic effects between GO and SWNT networks, and their enhanced contribution of the conductivity. These results indicate that this composite has potential for utilization in high-rate and durable LIBs.
基金NSFC (20471055)Henan Outstanding Youth Science Fund (0612002700)
文摘SnO2 doped with Y were prepared by co-precipitation method and tested in lithium-ion cells. The structure and morphology of the materials were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). XRD patterns presented that the all the as-prepared materials had tetragonal rutile structure but a second phase (Y2O3) was observed when Y content reached 4%. TEM micrograph indicated that Y doped SnO2 had a small particle size ranging from 20 to 25 nm. The electrochemical properties for an anode active material in lithium-ion batteries were investigated at room temperature, including the observed capacity involved in the first-discharge and the reversible capacity values during subsequent charge-discharge cycles. The as-prepared Y-doped SnO2 exhibited promising electrochemical properties as anodes for lithium-ion batteries.
基金the National Natural Science Foundation of China (20476070,20771080)Natural Science Foundation of Shanxi Province (20031024 ,20041020)
文摘The acid-proof anode Ti/SnO2+Mn2O3/PbO2 doped with Ce was prepared by thermal decomposition and electrodeposition combination technology, the effect of Ce on the morphology and structure of anode was also studied in this paper. The results obtained by cyclic voltammetry (CV), electrochemical impedance spectroscopic (EIS), X-ray Diffraction (XRD) and scanning electron microscopy (SEM) indicated that PbO2 crystal grains presented honeycomb structure were formed on the electrode surface by doping with Ce. The specific surface areas and catalytic active sites of the Ce-PbO2 doped electrode were increased and the catalytic activity was evidently greater than the undoped one. However, when Ce was doped into the intermediate layer (SnO2+Mn2O3), a more cracked surface structure formed, thus leading electrode deactivation by passivation of the Ti-substrate. So the anodic stability was decreased according to the accelerated life tests.
