Ba0.95Ce0.9Y0.1O3-α solid electrolyte was prepared by high temperature solid state reaction. The electrochemical oxygen permeation (oxygen pumping) rates and oxide ion transport number in this electrolyte were detec...Ba0.95Ce0.9Y0.1O3-α solid electrolyte was prepared by high temperature solid state reaction. The electrochemical oxygen permeation (oxygen pumping) rates and oxide ion transport number in this electrolyte were detected in the temperature of 600~ 1000℃ . It was found that this electrolyte exhibited the oxide ion conduction with the oxide ion transport number of 0.3~ 0.5.展开更多
BaxCe0.8Y0.2O3-α(x=1.03,1,0.98) solid electrolyte samples show a single phase of orthorhombic perovskite of BaCeO3. The oxide ion conduction and transport number were detected in the temperature of 600~1000℃by elec...BaxCe0.8Y0.2O3-α(x=1.03,1,0.98) solid electrolyte samples show a single phase of orthorhombic perovskite of BaCeO3. The oxide ion conduction and transport number were detected in the temperature of 600~1000℃by electrochemical oxygen permeation (oxygen pumping), and compared with the results from the oxygen concentration cell. The relation between the ingredient of Ba and oxide ion conduction was also researched. It was found that these electrolytes exhibited the mixed oxide ionic and electronic hole conduction under the experimental temperature and oxygen gas. The oxide ion transport numbers are 0.1~0.6, which are close to the results of the oxygen concentration cell. They increase as the decrease of Ba content in the samples.展开更多
Ni/YSZ fuel electrodes can only operate under strongly reducing conditions for steam elec- trolysis in an oxide-ion-conducting solid oxide electrolyzer (SOE). In atmosphere with a low content of H2 or without H2, ca...Ni/YSZ fuel electrodes can only operate under strongly reducing conditions for steam elec- trolysis in an oxide-ion-conducting solid oxide electrolyzer (SOE). In atmosphere with a low content of H2 or without H2, cathodes based on redox-reversible Nb2TiO7 provide a promising alternative. The reversible changes between oxidized Nb2TiO7 and reduced Nbl.33Tio.6704 samples are systematically investigated after redox-cycling tests. The conductivities of Nb2TiO7 and reduced Nb1.33Tio.6704 are studied as a function of temperature and oxygen partial pressure and correlated with the electrochemical properties of the composite electrodes in a symmetric cell and SOE at 830 ℃. Steam electrolysis is then performed using an oxide-ion-conducting SOE based on a Nb1.33Ti0.6704 composite fuel electrode at 830 ℃. The current-voltage and impedance spectroscopy tests demonstrate that the reduction and activation of the fuel electrode is the main process at low voltage; however, the steam electrolysis dominates the entire process at high voltages. The Faradic efficiencies of steam electrolysis reach 98.9% when 3%H2O/Ar/4%H2 is introduced to the fuel electrode and 89% for that with introduction of 3%H2O/Ar.展开更多
High volumetric specific capacitance is essential for flexible supercapacitors.In this paper,a flexible composite electrode with ultrahigh volumetric specific capacitance and good rate performance is designed and prep...High volumetric specific capacitance is essential for flexible supercapacitors.In this paper,a flexible composite electrode with ultrahigh volumetric specific capacitance and good rate performance is designed and prepared.The film electrode is composed of non-porous compact polyaniline as the matrix and a small amount of reduced graphene oxide sheets as the conductive filler.The film is prepared by a newly developed solution casting method,where the casting solution is obtained by self-assembly of polyaniline and graphene oxide in a blended solution.A systematical investigation on the effect of reduced graphene oxide sheets reveals that they serve as both the conductive filler and the diffusion barrier.With the optimized reduced graphene oxide content,a large volumetric specific capacitance of 1354 F cm^−3 at 2.4 A cm^−3 is achieved,and good rate performance is also obtained because of the good ionic conductivity of polyaniline.This work provides a high performance electrode for flexible supercapacitors,and the solution casting method is also valuable in fabricating other organic electrode materials.展开更多
文摘Ba0.95Ce0.9Y0.1O3-α solid electrolyte was prepared by high temperature solid state reaction. The electrochemical oxygen permeation (oxygen pumping) rates and oxide ion transport number in this electrolyte were detected in the temperature of 600~ 1000℃ . It was found that this electrolyte exhibited the oxide ion conduction with the oxide ion transport number of 0.3~ 0.5.
文摘BaxCe0.8Y0.2O3-α(x=1.03,1,0.98) solid electrolyte samples show a single phase of orthorhombic perovskite of BaCeO3. The oxide ion conduction and transport number were detected in the temperature of 600~1000℃by electrochemical oxygen permeation (oxygen pumping), and compared with the results from the oxygen concentration cell. The relation between the ingredient of Ba and oxide ion conduction was also researched. It was found that these electrolytes exhibited the mixed oxide ionic and electronic hole conduction under the experimental temperature and oxygen gas. The oxide ion transport numbers are 0.1~0.6, which are close to the results of the oxygen concentration cell. They increase as the decrease of Ba content in the samples.
文摘Ni/YSZ fuel electrodes can only operate under strongly reducing conditions for steam elec- trolysis in an oxide-ion-conducting solid oxide electrolyzer (SOE). In atmosphere with a low content of H2 or without H2, cathodes based on redox-reversible Nb2TiO7 provide a promising alternative. The reversible changes between oxidized Nb2TiO7 and reduced Nbl.33Tio.6704 samples are systematically investigated after redox-cycling tests. The conductivities of Nb2TiO7 and reduced Nb1.33Tio.6704 are studied as a function of temperature and oxygen partial pressure and correlated with the electrochemical properties of the composite electrodes in a symmetric cell and SOE at 830 ℃. Steam electrolysis is then performed using an oxide-ion-conducting SOE based on a Nb1.33Ti0.6704 composite fuel electrode at 830 ℃. The current-voltage and impedance spectroscopy tests demonstrate that the reduction and activation of the fuel electrode is the main process at low voltage; however, the steam electrolysis dominates the entire process at high voltages. The Faradic efficiencies of steam electrolysis reach 98.9% when 3%H2O/Ar/4%H2 is introduced to the fuel electrode and 89% for that with introduction of 3%H2O/Ar.
基金financially supported by the National Natural Science Foundation of China (21774104 and 21975210)the Natural Science Foundation of Fujian Province (2018J06015)
文摘High volumetric specific capacitance is essential for flexible supercapacitors.In this paper,a flexible composite electrode with ultrahigh volumetric specific capacitance and good rate performance is designed and prepared.The film electrode is composed of non-porous compact polyaniline as the matrix and a small amount of reduced graphene oxide sheets as the conductive filler.The film is prepared by a newly developed solution casting method,where the casting solution is obtained by self-assembly of polyaniline and graphene oxide in a blended solution.A systematical investigation on the effect of reduced graphene oxide sheets reveals that they serve as both the conductive filler and the diffusion barrier.With the optimized reduced graphene oxide content,a large volumetric specific capacitance of 1354 F cm^−3 at 2.4 A cm^−3 is achieved,and good rate performance is also obtained because of the good ionic conductivity of polyaniline.This work provides a high performance electrode for flexible supercapacitors,and the solution casting method is also valuable in fabricating other organic electrode materials.