Glass transition temperature(T
g) of 20BaO·10Fe
2O
3·xWO
3·(70−x)V
2O
5 glasses showed a step-by-step increase from 339 to 470°C when x was increased from 0 to 50, together with a concordant increase in crystallization temperature(T
c) from 406 to 531°C. Plot of T
g against quadrupole splitting(Δ) of Fe
III in the Mössbauer spectra yielded a straight line with a slope of 680K(mm s
−1)
−1. This indicates that Fe
III atoms constitute distorted FeO
4 tetrahedra and play a role of network former in the 3D-glass network. Dissolution of vanadium ions from vanadate glass into boiling water was suppressed from 34 to 2mg L
−1 when x was modified from 0 to 50, reflecting that introduction of WO
3 into the 3D-network of vanadate glass is effective in the improvement of water resistivity. A gradual decrease of Δ was observed from 0.82 to 0.76mm s
−1 after isothermal annealing of vanadate glass(x=20) at 500°C for 240min, indicating structural relaxation of the glass network, and a marked increase in conductivity (σ) from 3.9×10
−6 to 2.1×10
−3 S cm
−1 was observed at room temperature.
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