K2FeO4 powders were synthesized by the ex-situ and in-situ electrochemical methods, respectively, and characterized by infrared spectrum （IR）, scanning electron microscopy （SEM）, X-ray powder diffraction （XRD） a...K2FeO4 powders were synthesized by the ex-situ and in-situ electrochemical methods, respectively, and characterized by infrared spectrum （IR）, scanning electron microscopy （SEM）, X-ray powder diffraction （XRD） and BET. Their electrochemical performances were investigated by means of galvanostatic discharge and electrochemi-cal impedance spectroscopy （EIS）. The results of physical characterization showed that the two samples have simi-lar structural features, but their surface morphologies and oriented growth of the crystals are different, which results in smaller specific surface area and lower solubility of the ex-situ electrosynthesized K2FeO4 sample. The results of discharge experiments indicated that the ex-situ electrosythesized K2FeO4 electrode has much larger discharge ca-pacity and lower electrode polarization than the in-situ electrosynthesized K2FeO4 electrode. It was found from the results of EIS that lower electrochemical polarization might be responsible for the improvement on the discharge performance of the ex-situ electrosynthesized K2FeO4 electrode.展开更多
The materials used in fuel cells are currently the subject of much research, particularly those of the cathode which is a key element for the different functions that it provides. In our work the authors became intere...The materials used in fuel cells are currently the subject of much research, particularly those of the cathode which is a key element for the different functions that it provides. In our work the authors became interested in the different materials used for the cathode, which are usually ceramic, and some of their physical properties between different electrical conductivity （electronic, ionic）, the coefficient of thermal expansion and chemical compatibility between different materials used in the stack. Not to mention, however, the various parameters that influence these properties, such as structure, the sintering temperature, dope, and the operating temperature of the battery. The main objective of research in this area is to improve battery performance by researching new materials and new manufacturing technologies that will increase the electrical conductivity while trying to lower the temperature operating the latter as much as possible while keeping it above 650℃, In doing so, the longevity of the battery will be increased which will have a direct impact on manufacturing costs of the battery, and thus greater use thereof.展开更多
Proton-conducting oxides offer a promising electrolyte solution for intermediate temperature solid oxide fuel cells（SOFCs） due to their high conductivity and low activation energy. However, the lower operation tempe...Proton-conducting oxides offer a promising electrolyte solution for intermediate temperature solid oxide fuel cells（SOFCs） due to their high conductivity and low activation energy. However, the lower operation temperature leads to a reduced cathode activity and thus a poorer fuel cell performance. La_（0.8）Sr_（0.2）MnO_（3-δ）（LSM） is the classical cathode material for high-temperature SOFCs, which lack features as a proper SOFC cathode material at intermediate temperatures.Despite this, we here successfully couple nanostructured LSM cathode with proton-conducting electrolytes to operate below600℃ with desirable SOFC performance. Inkjet printing allows depositing nanostructured particles of LSM on Y-doped Ba ZrO_3（BZY） backbones as cathodes for proton-conducting SOFCs, which provides one of the highest power output for the BZY-based fuel cells below 600 ℃. This somehow changes the common knowledge that LSM can be applied as a SOFC cathode materials only at high temperatures（above 700 ℃）.展开更多
基金Supported by the National Natural Science Foundation of China (No.50172041)partly by the Chinese State Key Labora-tory for Corrosion and Protection.
文摘K2FeO4 powders were synthesized by the ex-situ and in-situ electrochemical methods, respectively, and characterized by infrared spectrum （IR）, scanning electron microscopy （SEM）, X-ray powder diffraction （XRD） and BET. Their electrochemical performances were investigated by means of galvanostatic discharge and electrochemi-cal impedance spectroscopy （EIS）. The results of physical characterization showed that the two samples have simi-lar structural features, but their surface morphologies and oriented growth of the crystals are different, which results in smaller specific surface area and lower solubility of the ex-situ electrosynthesized K2FeO4 sample. The results of discharge experiments indicated that the ex-situ electrosythesized K2FeO4 electrode has much larger discharge ca-pacity and lower electrode polarization than the in-situ electrosynthesized K2FeO4 electrode. It was found from the results of EIS that lower electrochemical polarization might be responsible for the improvement on the discharge performance of the ex-situ electrosynthesized K2FeO4 electrode.
文摘The materials used in fuel cells are currently the subject of much research, particularly those of the cathode which is a key element for the different functions that it provides. In our work the authors became interested in the different materials used for the cathode, which are usually ceramic, and some of their physical properties between different electrical conductivity （electronic, ionic）, the coefficient of thermal expansion and chemical compatibility between different materials used in the stack. Not to mention, however, the various parameters that influence these properties, such as structure, the sintering temperature, dope, and the operating temperature of the battery. The main objective of research in this area is to improve battery performance by researching new materials and new manufacturing technologies that will increase the electrical conductivity while trying to lower the temperature operating the latter as much as possible while keeping it above 650℃, In doing so, the longevity of the battery will be increased which will have a direct impact on manufacturing costs of the battery, and thus greater use thereof.
基金supported by the National Natural Science Foundation of China (51602238)the Thousand Talents Plan
文摘Proton-conducting oxides offer a promising electrolyte solution for intermediate temperature solid oxide fuel cells（SOFCs） due to their high conductivity and low activation energy. However, the lower operation temperature leads to a reduced cathode activity and thus a poorer fuel cell performance. La_（0.8）Sr_（0.2）MnO_（3-δ）（LSM） is the classical cathode material for high-temperature SOFCs, which lack features as a proper SOFC cathode material at intermediate temperatures.Despite this, we here successfully couple nanostructured LSM cathode with proton-conducting electrolytes to operate below600℃ with desirable SOFC performance. Inkjet printing allows depositing nanostructured particles of LSM on Y-doped Ba ZrO_3（BZY） backbones as cathodes for proton-conducting SOFCs, which provides one of the highest power output for the BZY-based fuel cells below 600 ℃. This somehow changes the common knowledge that LSM can be applied as a SOFC cathode materials only at high temperatures（above 700 ℃）.
