| 摘要 |
The invention relates to binary and ternary mesostructured oxides employed in manufacturing the electrodes of the SOFC-type fuel cells with solid electrolyte and to a process for the synthesis thereof. According to the invention, the oxides exhibit solid nanoparticles of sizes ranging between 6...10 nm, they have a crystalline structure, spheric morphology and high dimensional uniformity, the solids have a poorly ordered porous structure made of mesopores, where the pores have a narrow distribution and an average diameter ranging between 2...8 nm and the specific surface ranges between 100...150 m/g. The process claimed by the invention consists in organizing the phases by dispersing the surface-active agents in the bidistilled water, admixing the metal precursors so that the metal : surface-active agent ratio varies between 2...4, homogenizing and initiating a hydrolysis process by admixture of urea, where the surface-active agent : urea ratio is maintained at the value of 0.05, after the admixture of urea the working temperature being increased to 40...80°C and maintained at this level for 4...8 h, the gelling process being initiated by adjusting the pH value at 9 or 10, using 25% aqueous solution of tetramethyl ammonium hydroxide and, after an ageing interval of 6...24 h at the ambient temperature, the hydrothermal treatment is performed at temperatures ranging between 80...120°C for 1...4 days, the resulting precipitate being filtered and washed with distilled water, dried for 12 hours at 100°C and calcined at 550°C for 8 hours in a nitrogen flow followed by an air flow. |
