Electrical conductivity of Cu/(10NiO-NiFe₂O₄) cermet inert anode for aluminum electrolysis

Abstract

Cu/(10NiO-NiFe₂O₄) cermets containing mass fractions of Cu of 5%, 10%, 15% and 20% were prepared, and their electrical conductivities were measured at different temperatures. The effects of temperature and content of metal Cu on the electrical conductivity were investigated especially. The results indicate that the metallic phase Cu distributes evenly in 10NiO-NiFe₂O₄ ceramic matrix. The mechanism of electrical conductivity of Cu/(10NiO-NiFe₂O₄) cermets obeys the rule of electrical mechanism of semiconductor, the electrical conductivity for cermet containing 5% Cu increases from 2.70 to 20.41 S/cm with temperature increasing from 200 to 900 °C. The change trend of electrical conductivity with temperature is similar with each other and it increases with increasing temperature and content of metal Cu. At 960 °C, the electrical conductivity of cermet increases from 2.88 to 82.65 S/cm with the content of metal Cu increasing from 0 to 20%.

Keywords

NiFe₂O₄ / NiO / cermet / inert anode / aluminum electrolysis / electrical conductivity