M. Colmont, M. Drache, P. Roussel
Nov 1, 2010
Citations
1
Influential Citations
8
Citations
Journal
Journal of Power Sources
Abstract
Abstract Single crystals, as well as pure powder of the new bismuth chromate, Bi 31 Cr 5 O 61.5 were synthesized by slow cooling of a mixture of Bi 2 O 3 –Cr 2 O 3 and then fully structurally characterized using X-ray diffraction. It crystallizes in the monoclinic space group P2 1 /n with unit cell parameters a = 23.5794(8), b = 11.6189(4), c = 24.3629(8) A and β = 108.02(1)°, Z = 4. The final conventional agreement factors converged to R = 0.0540 and w R = 0.0561 for 27520 independent reflections. The +VI chromium oxidation state was proved by thermogravimetric and magnetic measurements. The structure can be described by the association of isolated CrO 4 tetrahedra surrounded by 11 or 12 Bi atoms forming truncated or not cuboctahedra. The stability of both pure powder sample and pressed sintered pellets was studied at elevated temperature by X-ray diffraction and by dilatometry previously to ionic conductivity measurements done by impedance spectroscopy.