Sulfur-oxygen solid oxide fuel cells （S/O2-SOFCs） can improve the utilization ratio of energy via converting the combustion heat of sulfur into electrical energy directly, and sulfur trioxide which is an intermediat...Sulfur-oxygen solid oxide fuel cells （S/O2-SOFCs） can improve the utilization ratio of energy via converting the combustion heat of sulfur into electrical energy directly, and sulfur trioxide which is an intermediate in sulfuric acid industry can be obtained directly via S/O2-SOFCs. The anode material NdFeO3 was prepared via sol-gel method, the phase stability of NdFeO3 in sulfur vapor or sulfur dioxide atmosphere was investigated. The single cell, consisting of NdFeO3-SDC/SDC/LSM-SDC structure, was fabricated by the screen-printing method and tested by the home-built equipment with sulfur vapor or sulfur dioxide as the fuel. As indicated by X-ray diffraction （XRD） analysis, NdFeO3 was stable in sulfur vapor or sulfur dioxide atmosphere at 800℃, the phase composition of the mixture of NdFeO3 and SDC （Sm doped CeO2） did not change after the mixture was calcined at 800 ℃ for 4 h. The transmission electron microscope （TEM） photograph revealed that the average grain size of NdFeO3 powder was about 80 nm. With sulfur vapor or SO2 as the fuel, the maximum open circuit voltages （OCVs） of the single cell were 409 mV at 620 ℃ and 474 mV at 650 ℃, respectively; the maximum power densities of single cell were 0.154 mW/cm^2 at 620 ℃ and 0.265 mW/cm^2 at 650 ℃, respectively.展开更多
The defect dipoles exist in ferroelectric thin films and they play a unique role in the domain structure.However,most of the previous studies of the ferroelectric domains involve the extrinsic field-induced polarizati...The defect dipoles exist in ferroelectric thin films and they play a unique role in the domain structure.However,most of the previous studies of the ferroelectric domains involve the extrinsic field-induced polarization reverse.Herein,we report domain reorientation induced by the realignment of the defect dipoles at high temperatures in a(100)-oriented NdFeO_(3)-PbTiO_(3)(NF-PT)thin film.The temperature-dependent XRD results exclude the reorientation of the lattice structures,and the macroscopic ferroelectric hysteresis loop at 150℃shows greater conductivity,which is induced by the emergence of the out-of-plane defect dipoles.The present study provides a picture to understand the thermal activation of the defect dipoles,which will benefit novel ferroelectric devices.展开更多
基金supported by National Natural Science Foundation of China (50975002,90289008)Graduate Innovation Fund of Anhui University of Technology (2011011)Research Project for University Personnel Returning from Overseas sponsored by the Ministry of Education of China (90289008)
文摘Sulfur-oxygen solid oxide fuel cells （S/O2-SOFCs） can improve the utilization ratio of energy via converting the combustion heat of sulfur into electrical energy directly, and sulfur trioxide which is an intermediate in sulfuric acid industry can be obtained directly via S/O2-SOFCs. The anode material NdFeO3 was prepared via sol-gel method, the phase stability of NdFeO3 in sulfur vapor or sulfur dioxide atmosphere was investigated. The single cell, consisting of NdFeO3-SDC/SDC/LSM-SDC structure, was fabricated by the screen-printing method and tested by the home-built equipment with sulfur vapor or sulfur dioxide as the fuel. As indicated by X-ray diffraction （XRD） analysis, NdFeO3 was stable in sulfur vapor or sulfur dioxide atmosphere at 800℃, the phase composition of the mixture of NdFeO3 and SDC （Sm doped CeO2） did not change after the mixture was calcined at 800 ℃ for 4 h. The transmission electron microscope （TEM） photograph revealed that the average grain size of NdFeO3 powder was about 80 nm. With sulfur vapor or SO2 as the fuel, the maximum open circuit voltages （OCVs） of the single cell were 409 mV at 620 ℃ and 474 mV at 650 ℃, respectively; the maximum power densities of single cell were 0.154 mW/cm^2 at 620 ℃ and 0.265 mW/cm^2 at 650 ℃, respectively.
基金supported by the National Natural Science Foundation of China(Grant No.21590793 and 21731001)the National Science Foundation of ShanXi(Grant No.201701D221070)+1 种基金the Program for Changjiang Scholars,the Innovative Research Team in University(Grant No.IRT1207)the Program of Introducing Talents of Discipline to Universities(Grant No.B14003)。
文摘The defect dipoles exist in ferroelectric thin films and they play a unique role in the domain structure.However,most of the previous studies of the ferroelectric domains involve the extrinsic field-induced polarization reverse.Herein,we report domain reorientation induced by the realignment of the defect dipoles at high temperatures in a(100)-oriented NdFeO_(3)-PbTiO_(3)(NF-PT)thin film.The temperature-dependent XRD results exclude the reorientation of the lattice structures,and the macroscopic ferroelectric hysteresis loop at 150℃shows greater conductivity,which is induced by the emergence of the out-of-plane defect dipoles.The present study provides a picture to understand the thermal activation of the defect dipoles,which will benefit novel ferroelectric devices.
