Sub-micron-scaled sodium cobalt oxide （NaCo2O4） powders are prepared by a solid-state reaction method. Characterization using X-ray diffraction indicates that the synthesized NaCo2O4 has a hexagonal layered structur...Sub-micron-scaled sodium cobalt oxide （NaCo2O4） powders are prepared by a solid-state reaction method. Characterization using X-ray diffraction indicates that the synthesized NaCo2O4 has a hexagonal layered structure. The electrochemical performance of the NaCo2O4 electrodes is investigated using cyclic voltarnmetry and galvanostatic charge/discharge in NaOH solution. The results show that the specific capacitance of the NaCo2O4 electrode reaches 337 F/g over the potential range of 0.15-0.65 V at a mass normalized current of 50 mA/g. Moreover, NaCo2O4 exhibits very good stability and cycling performance as a supercapacitor material.展开更多
利用溶胶-凝胶法和固相烧结法制备了单相钙钛矿型Sm Ba Cu Fe1-xCoxO5+δ(x=0,0.3,0.5,0.7)陶瓷。样品的致密度较高,均在90%以上。在303~1023 K的温度范围内测试了其电导率和Seebeck系数。样品的电导率随着x值的增大而明显增加,在1023 ...利用溶胶-凝胶法和固相烧结法制备了单相钙钛矿型Sm Ba Cu Fe1-xCoxO5+δ(x=0,0.3,0.5,0.7)陶瓷。样品的致密度较高,均在90%以上。在303~1023 K的温度范围内测试了其电导率和Seebeck系数。样品的电导率随着x值的增大而明显增加,在1023 K时电导率从0.75 S/cm提高到了41.24 S/cm。拟合电阻率与温度的关系,得到的激活能值随着x值的增大加而明显降低,从0.38 e V降低到0.23 e V。综合电导率和Seebeck系数,确定了Fe位替换Co的最佳浓度在x=0.3附近,Sm Ba Cu Fe0.7Co0.3O5+δ样品的功率因子随着温度升高而增加,在1023 K时最高可达0.241μW·cm-1·K-2。展开更多
基金financially supported by the Natural Science Foundation of China(No.21071046)
文摘Sub-micron-scaled sodium cobalt oxide （NaCo2O4） powders are prepared by a solid-state reaction method. Characterization using X-ray diffraction indicates that the synthesized NaCo2O4 has a hexagonal layered structure. The electrochemical performance of the NaCo2O4 electrodes is investigated using cyclic voltarnmetry and galvanostatic charge/discharge in NaOH solution. The results show that the specific capacitance of the NaCo2O4 electrode reaches 337 F/g over the potential range of 0.15-0.65 V at a mass normalized current of 50 mA/g. Moreover, NaCo2O4 exhibits very good stability and cycling performance as a supercapacitor material.
文摘利用溶胶-凝胶法和固相烧结法制备了单相钙钛矿型Sm Ba Cu Fe1-xCoxO5+δ(x=0,0.3,0.5,0.7)陶瓷。样品的致密度较高,均在90%以上。在303~1023 K的温度范围内测试了其电导率和Seebeck系数。样品的电导率随着x值的增大而明显增加,在1023 K时电导率从0.75 S/cm提高到了41.24 S/cm。拟合电阻率与温度的关系,得到的激活能值随着x值的增大加而明显降低,从0.38 e V降低到0.23 e V。综合电导率和Seebeck系数,确定了Fe位替换Co的最佳浓度在x=0.3附近,Sm Ba Cu Fe0.7Co0.3O5+δ样品的功率因子随着温度升高而增加,在1023 K时最高可达0.241μW·cm-1·K-2。
