ИСТИНА

CeO2 nanostructures of different morphology were synthesized under hydrothermal conditions. The structure, elemental composition, shape and size of the obtained nanoobjects were analyzed using the X-ray diffraction, energydispersive X-ray spectroscopy and transmission electron microscopy. It was shown that hydrothermal treatment of cerium nitrate at 180°C, 15 MPa in strongly alkaline solutions for 24 hour leads to the formation of cubic CeO2 nanoparticles with a wide size distribution. In case of carrying out the synthesis at lower temperatures and simultaneously increasing the alkali content in the composition of the hydrothermal medium, CeO2 crystallizes in the form of rods with a diameter of 10 nm and a length of 200 nm. Electrochemical properties of prepared oxides were tested in standard 3-electrode cell. The working electrodes were prepared by dispersing of oxide in the DMF solution containing carbon black, PVDF. The glass carbon electrode with working area 1.3 cm2 was covered with 0.3 ml of prepared dispersion and dried at 60°C. Cyclic voltammetry and galvanostatic charge discharge experiments were performed with the CeO2 with different morphology in the potential range -0.2V – +0.5V vs Ag/AgCl reference electrode. The results demonstrate that CeO2 in the form of cubes has significantly higher specific capacitance in comparison with CeO2 rods. This can be attributed to the difference in the specific surface area of these oxides.