A Study on Conductivity of (Zr_(1-x)M_x)O_2 Ceramic

In the ZrO_2 ceramic systems doped with different oxides (Y_2O_3, MgO and Al_2O_3), the electronic energy spectroscopy and local density of states were calculated by a theoretical quantumchendcal method, and compared with the behaviors of electronic and ionic conduction. The resultsshowed that for the system doped with Al_2O_3, the energy gap near the Fermi energy level becomessmaller, so that the electronic couduction increases; the binding energy between Al and O atomincreases, which enhances the energy for vacancy migrating, the ionic conduction decreases. Onthe coutrary the systems doped with Y_2O_3 show a large ionic conduction, but a weaker electronicconduction. The effect of MgO is just between above two systems. The mentioned results agreewith that of references and experiments.