The d.c. conductivity (σ) of (a) glasses prepared by the press-quenching method and (b) glass-ceramics (crystallized glass) produced by post-heat treatment was investigated in the system Sb2O3–CaO–V2O5 and their conduction mechanism was studied. The glasses were n-type semiconductors with σ = 2.6 × 10-6 ∼ 2.8 × 10-5 S cm-1 at 333 K for varying glass compositions. The conduction was attributed to small polaron hopping in the adiabatic regime. The estimated carrier density was 1.7 ∼ 3.8 × 1021 cm-3 for V2O5 = 70 ∼ 80 mol% and the mobility was 3.5 × 10-9 to 6.9 × 10-8 cm2 V-1 s-1.
Crystallization raised the conductivity by a factor of 103. The crystalline product in the glass-ceramics was Ca0.17V2O5. The glass-ceramics were n-type semiconductors, and the conduction was interpreted by a superposition of the small polaron hopping in the crystalline and glassy phases.