The Ag/Mg0.2Zn0.8O/ZnMn2O4/p^＋-Si heterostructure devices were fabricated by sol-gel spin coating technique and the resistive switching behavior,conduction mechanism,endurance characteristic,and retention properties ...The Ag/Mg0.2Zn0.8O/ZnMn2O4/p^＋-Si heterostructure devices were fabricated by sol-gel spin coating technique and the resistive switching behavior,conduction mechanism,endurance characteristic,and retention properties were investigated.A distinct bipolar resistive switching behavior of the devices was observed at room temperature.The resistance ratio R_（HRS）/RLRS of high resistance state and low resistance state is as large as four orders of magnitude with a readout voltage of 2.0 V.The dominant conduction mechanism of the device is trap-controlled space charge limited current（SCLC）.The devices exhibit good durability under 1×10^3cycles and the degradation is invisible for more than 10^6 s.展开更多
Columbite Zn0.8Co0.2Nb2O6 crystals were grown by optical floating zone methods. The x-ray diffraction(XRD) was used to check the structure information of the grown Zn0.8Co0.2Nb2O6 crystal. The room temperature and tem...Columbite Zn0.8Co0.2Nb2O6 crystals were grown by optical floating zone methods. The x-ray diffraction(XRD) was used to check the structure information of the grown Zn0.8Co0.2Nb2O6 crystal. The room temperature and temperature-dependent Raman spectra were tested to investigate the optical phonon behaviors of columbite Zn0.8Co0.2Nb2O6, which exhibited a temperature stable property. The magnetics properties of Zn0.8Co0.2Nb2O6, measured by a physical property measurement system(PPMS), were also presented in this work.展开更多
NiO-La0.3Ce0.7O2-δ(LDC30) novel anode was investigated for IT-SOFCs(Intermediate Temperature-Solid Oxide Fuel Cells) with LaGaO3-based electrolyte. The results showed that LDC30 has a suitable chemical compatibility ...NiO-La0.3Ce0.7O2-δ(LDC30) novel anode was investigated for IT-SOFCs(Intermediate Temperature-Solid Oxide Fuel Cells) with LaGaO3-based electrolyte. The results showed that LDC30 has a suitable chemical compatibility with NiO and NiO-LDC30 has a good thermal expansion matching with LDC30 interlayer and LSGM(La0.8Sr0.2Ga0.8Mg0.2O3-δ) electrolyte, so NiO-LDC30/LDC30 was considered as a feasible and novel anode system. It was also shown that NiO content plays a key role on polarization performance and morphology of the anode. When the content of NiO was 60%(mass fraction), the polarization loss of anode was the lowest. Next we will optimize the porosity and sintering procedure to modify the microstructure and performance of the anode.展开更多
Compound Zn2Sn0.8Ti0.2O4 was synthesized by a hydrothermal method in which SnCl4-5H2O,TiCl4,ZnCl2 and N2H4-H2O were used as reactants.The composite Zn2Sn0.8Ti0.2O4/C was then prepared through a carbothermic reduction ...Compound Zn2Sn0.8Ti0.2O4 was synthesized by a hydrothermal method in which SnCl4-5H2O,TiCl4,ZnCl2 and N2H4-H2O were used as reactants.The composite Zn2Sn0.8Ti0.2O4/C was then prepared through a carbothermic reduction process using the as-prepared Zn2Sn0.8Ti0.2O4 and glucose as reactants.The structure,morphology and electrochemical properties of the as-prepared products were investigated by XRD,XPS,TEM and electrochemical measurements.In addition,electrochemical Li insertion/extraction in composite Zn2Sn0.8Ti0.2O4/C were examined by ex situ XRD and SEM.The first discharge capacity of Zn2SnO4 is about 1670.8 mA-h/g,with a capacity retain of 342.7 mA-h/g in the 40th cycle at a constant current density of 100 mA/g in the voltage range of 0.05-3.0 V.Comparing with the Zn2SnO4,some improved electrochemical properties are obtained for Zn2Sn0.8Ti0.2O4,Zn2SnO4/C and Zn2Sn0.8Ti0.2O4/C.The composite Zn2Sn0.8Ti0.2O4/C shows the best electrochemical properties,and its first discharge capacity is about 1530.0 mA-h/g,with a capacity retain of 479.1 mA-h/g the 100th cycle.展开更多
Ce0.8Sm0.2O1.9-δ-La0.9Sr0.1Ga0.8Mg0.2O3-δ（SDC-LSGM）is prepared by the glycine-nitrate process（GNP）.SDC-LSGM composite electrolyte samples with different weight ratios are prepared by the co-combustion method so ...Ce0.8Sm0.2O1.9-δ-La0.9Sr0.1Ga0.8Mg0.2O3-δ（SDC-LSGM）is prepared by the glycine-nitrate process（GNP）.SDC-LSGM composite electrolyte samples with different weight ratios are prepared by the co-combustion method so as to obtain homogeneous nano-sized precursor powders. The X-ray diffraction （XRD） and the scan electron microscope （SEM） are used to investigate the phases and microstructures. The measurements and analyses of oxygen ionic conductivity of SDC-LSGM are carried out through the four-terminal direct current （DC） method and the electrochemical impendence spectroscopy, respectively. The optimum weight ratio of SDC-LSGM is 8∶2, of which the ionic conductivity is 0.113 S/cm at 800℃ and the conductivity activation energy is 0.620 eV. The impendence spectra shows that the grain boundary resistance becomes the main barrier for the ionic conductivity of electrolyte at lower temperatures. The appropriate introduction of LSGM to the electrolyte SDC can not only decrease the electronic conductivity but also improve the conditions of the grain and grain boundary, which is advantageous to cause an increase in oxygen ionic conductivity.展开更多
基金Funded by the National Natural Science Foundation of China(No.51262003)the Guangxi Key Laboratory of Information Materials(Guilin University of Electronic Technology),China(No.1110908-10-Z)
文摘The Ag/Mg0.2Zn0.8O/ZnMn2O4/p^＋-Si heterostructure devices were fabricated by sol-gel spin coating technique and the resistive switching behavior,conduction mechanism,endurance characteristic,and retention properties were investigated.A distinct bipolar resistive switching behavior of the devices was observed at room temperature.The resistance ratio R_（HRS）/RLRS of high resistance state and low resistance state is as large as four orders of magnitude with a readout voltage of 2.0 V.The dominant conduction mechanism of the device is trap-controlled space charge limited current（SCLC）.The devices exhibit good durability under 1×10^3cycles and the degradation is invisible for more than 10^6 s.
基金Supported by the National Basic Research Program of China (973 Program,2010CB732300)the National Natural Science Foundation of China (20673037,20601008)the National Key Technologies R&D Program of China (2007BAJ03B01)
基金Project supported by the National Key Research and Development Program of China(Grant No.2017YFA0403704)the National Natural Science Foundation of China(Grant Nos.11304113,11474127,and 11574112)the Fundamental Research Funds for the Central Universities of China
文摘Columbite Zn0.8Co0.2Nb2O6 crystals were grown by optical floating zone methods. The x-ray diffraction(XRD) was used to check the structure information of the grown Zn0.8Co0.2Nb2O6 crystal. The room temperature and temperature-dependent Raman spectra were tested to investigate the optical phonon behaviors of columbite Zn0.8Co0.2Nb2O6, which exhibited a temperature stable property. The magnetics properties of Zn0.8Co0.2Nb2O6, measured by a physical property measurement system(PPMS), were also presented in this work.
文摘NiO-La0.3Ce0.7O2-δ(LDC30) novel anode was investigated for IT-SOFCs(Intermediate Temperature-Solid Oxide Fuel Cells) with LaGaO3-based electrolyte. The results showed that LDC30 has a suitable chemical compatibility with NiO and NiO-LDC30 has a good thermal expansion matching with LDC30 interlayer and LSGM(La0.8Sr0.2Ga0.8Mg0.2O3-δ) electrolyte, so NiO-LDC30/LDC30 was considered as a feasible and novel anode system. It was also shown that NiO content plays a key role on polarization performance and morphology of the anode. When the content of NiO was 60%(mass fraction), the polarization loss of anode was the lowest. Next we will optimize the porosity and sintering procedure to modify the microstructure and performance of the anode.
基金Project (51004028) supported by the National Natural Science Foundation of China
文摘Compound Zn2Sn0.8Ti0.2O4 was synthesized by a hydrothermal method in which SnCl4-5H2O,TiCl4,ZnCl2 and N2H4-H2O were used as reactants.The composite Zn2Sn0.8Ti0.2O4/C was then prepared through a carbothermic reduction process using the as-prepared Zn2Sn0.8Ti0.2O4 and glucose as reactants.The structure,morphology and electrochemical properties of the as-prepared products were investigated by XRD,XPS,TEM and electrochemical measurements.In addition,electrochemical Li insertion/extraction in composite Zn2Sn0.8Ti0.2O4/C were examined by ex situ XRD and SEM.The first discharge capacity of Zn2SnO4 is about 1670.8 mA-h/g,with a capacity retain of 342.7 mA-h/g in the 40th cycle at a constant current density of 100 mA/g in the voltage range of 0.05-3.0 V.Comparing with the Zn2SnO4,some improved electrochemical properties are obtained for Zn2Sn0.8Ti0.2O4,Zn2SnO4/C and Zn2Sn0.8Ti0.2O4/C.The composite Zn2Sn0.8Ti0.2O4/C shows the best electrochemical properties,and its first discharge capacity is about 1530.0 mA-h/g,with a capacity retain of 479.1 mA-h/g the 100th cycle.
基金The National Basic Research Program of China (973 Program) (No.2007CB936300)the Natural Science Foundation of Jiangsu Province (No.BK2009293)
文摘Ce0.8Sm0.2O1.9-δ-La0.9Sr0.1Ga0.8Mg0.2O3-δ（SDC-LSGM）is prepared by the glycine-nitrate process（GNP）.SDC-LSGM composite electrolyte samples with different weight ratios are prepared by the co-combustion method so as to obtain homogeneous nano-sized precursor powders. The X-ray diffraction （XRD） and the scan electron microscope （SEM） are used to investigate the phases and microstructures. The measurements and analyses of oxygen ionic conductivity of SDC-LSGM are carried out through the four-terminal direct current （DC） method and the electrochemical impendence spectroscopy, respectively. The optimum weight ratio of SDC-LSGM is 8∶2, of which the ionic conductivity is 0.113 S/cm at 800℃ and the conductivity activation energy is 0.620 eV. The impendence spectra shows that the grain boundary resistance becomes the main barrier for the ionic conductivity of electrolyte at lower temperatures. The appropriate introduction of LSGM to the electrolyte SDC can not only decrease the electronic conductivity but also improve the conditions of the grain and grain boundary, which is advantageous to cause an increase in oxygen ionic conductivity.
