The Preparation Of LaSr₃Fe_3-xCo_xO_10-? And Its Electrochemical Performance

As a class of novel energy storage device, electrochemical supercapacitors?ECs? have attracted great interest for their advantages such as high power density, short charging-discharging time and long cycling life. The electrode materials, a compartment of ECS, play a vital role in the electrochemical performances.In the present paper, LaSr₃Fe₃O_10-?-based oxides, a perovskite-related intergrowth oxide belonging to the n = 3?AO??ABO3?n Ruddlesden- Popper?R–P? series, has been studied as electrode materials for ECS. The combination processes of hydrothermal method and subsequent heat treatment were used to synthesis LaSr₃Fe₃O_10-?-based oxides. The effects of Co and Ni substitution for Fe on the electrochemical performance were studied by means of cyclic voltammetry, galvanostatic charge-discharge techniques and electrochemical impedance spectroscopy. The main content of this paper are listed below:?1?LaSr₃Fe₃O_10-? were synthesised by means of hydrothermal method. The calcination temperature effects study showed that powers calcined at 900?, though not purely single phase composed, posses larger specific surface area and specific capacity than powers calcined at 1000?. The specific capacity for LaSr₃Fe₃O_10-? calcined at 900? and 1000? are 603.5 F/g and 470.0 F/g at a scan rate of 1mV/s,and 360.1 F/g and 379.8 F/g at a charge-discharge current density of 0.1 A/g, respectively.?2?La Sr3Fe3-xCoxO10?x=0.5, 1.0, 1.5? were prepared using hydrothermal method. Cyclic voltammetry and galvanostatic charge-discharge results displayed a specific capatity as high as 763.3 F/g at a scan rate of 1mV/s and 450.4 F/g at a charge-discharge current density of 0.1 A/g for La Sr3Fe2CoO10 electorde material,which are higher than those values for Co content x = 0, 0.5, and 1.5 samples.?3?As La Sr3Fe2CoO10 electorde material exihibited relativily superior electrochemical properties, its analogous La Sr3Fe2NiO10 was synthesized by hydrothermal method and studied as electrode material. Electrochemical results showed that the specific capacitance of La Sr3Fe2NiO10 are 479.4 F/g at a scan rate of 1mV/s and 301.4 F/g at a charge-discharge current density of 0.1 A/g.