TY - JOUR
T1 - Study on conductivity and redox stability of iron orthovanadate
AU - Cowin, Peter Ian
AU - Lan, Rong
AU - Zhang, Lei
AU - Petit, Christophe TG
AU - Kraft, Arno
AU - Tao, Shanwen
PY - 2011
Y1 - 2011
N2 - FeVO(4) was synthesised by conventional solid state technique. Impedance measurements using a silver electrode were unsuccessful due to a solid state reaction between FeVO(4) and Ag, forming alpha-AgVO(3) and alpha-Fe(2)O(3) at the interface. Impedance measurements, with a platinum electrode, reaffirmed that FeVO(4) exhibits semiconductor behaviour in air. In a reducing atmosphere, 5 H(2)/Ar, high electronic conductivity, from 1 S cm(-1) at 300 degrees C to 2 S cm(-1) at 700 degrees C, was observed with an activation energy of 0.13(1) eV. X-ray diffraction, thermogravimetric analysis and differential scanning calorimetry data determined that the change in electronic conductivity was due to the degradation of the material into FeV(2)O(4) and alpha-Fe(2)O(3). It is believed that the conduction was due to electron hopping between vanadium d-orbitals. Neither FeVO(4) nor FeV(2)O(4) are deemed suitable as anode materials for solid oxide fuel cells, due to redox instability.
AB - FeVO(4) was synthesised by conventional solid state technique. Impedance measurements using a silver electrode were unsuccessful due to a solid state reaction between FeVO(4) and Ag, forming alpha-AgVO(3) and alpha-Fe(2)O(3) at the interface. Impedance measurements, with a platinum electrode, reaffirmed that FeVO(4) exhibits semiconductor behaviour in air. In a reducing atmosphere, 5 H(2)/Ar, high electronic conductivity, from 1 S cm(-1) at 300 degrees C to 2 S cm(-1) at 700 degrees C, was observed with an activation energy of 0.13(1) eV. X-ray diffraction, thermogravimetric analysis and differential scanning calorimetry data determined that the change in electronic conductivity was due to the degradation of the material into FeV(2)O(4) and alpha-Fe(2)O(3). It is believed that the conduction was due to electron hopping between vanadium d-orbitals. Neither FeVO(4) nor FeV(2)O(4) are deemed suitable as anode materials for solid oxide fuel cells, due to redox instability.
UR - http://goo.gl/obXa4u
U2 - 10.1016/j.matchemphys.2011.01.009
DO - 10.1016/j.matchemphys.2011.01.009
M3 - Article
SN - 0254-0584
VL - 126
SP - 614
EP - 618
JO - Materials Chemistry and Physics
JF - Materials Chemistry and Physics
IS - 3
ER -