Siberian Federal University

Using the Pechini method, a phase-pure and highly dispersed complex oxide Bi2Ni0.5Co0.5Ta2O9+∆ (space group Fd -3m, a=10.5348(5) Å) with a pyrochlore structure was synthesized. At a synthesis temperature of 1050 ºC, highly porous ceramics are formed with an average crystallite grain size of 41 nm according to X-ray diffraction data. The results of elemental mapping indicate a uniform distribution of atoms of transition elements in the sample, and X-ray energy dispersive analysis showed that the chemical composition of the synthesized sample corresponded to the specified theoretical composition. The formation of the pyrochlore phase proceeds through the formation of of an intermediate phase – bismuth orthotantalate of the orthorhombic modification, the content of which decreases with increasing heat treatment temperature from 16 (850 ºC) to 2 mol.% (950 ºC)