I–V characteristics in Nb2VSbO10-ceramics

Thermoelectric power and electrical resistivity as well as magnetic measurements carried out on Nb2VSbO10 showed a diamagnetic behavior, an insulating state up to 360 K and above this temperature n-type semiconducting properties with the activation energy of 0.55 eV. The I–V characteristics both at 300 and 400 K are symmetric and non-linear (back to back varistor-like). A computer-assisted curve fitting procedure of the conductance G vs. the applied voltage V showed the relation G ~ V3/4, which is interpreted in a framework of deep donor and shallow trap levels as well as grain boundaries.