Interpretation of dc and ac conductivity of Ag2O–SeO2–MoO3 glass-nanocomposite-semiconductor

• Polaron hopping.
• Dc and ac conductivity.
• Mott's model and Greave's model.
• Ag2MoO4, Ag2Mo2O7 and Ag6Mo10O33 nanoparticles and SeO3 and SeO4 nanoclusters.
• XRD and FESEM studies.

A new type of semiconducting glass-nanocomposites 0.3Ag2O–0.7 (xMoO3–(1 − x) SeO2) is prepared by melt-quenching route. The formation of Ag2MoO4, Ag2Mo2O7 and Ag6Mo10O33 nanoparticles and SeO3 and SeO4 nanoclusters in glass-nanocomposites has been confirmed from X-ray diffraction (XRD) and field emission scanning electron microscopic (FESEM) studies. Fourier transform infrared (FTIR) spectroscopy is employed to find out SeO stretching vibration as well as stretching vibrations of Mo2O72− ions. The dc conductivity of them is studied on the light of polaron hopping approach in a wide temperature range. At low temperatures, variable range hopping model (Mott's model) is employed to analyze the conductivity data. Greave's model is used to predict temperature dependent variable range hopping in the high temperature region. Frequency dependent ac conductivity is well explained on the basis of tunneling. I–V characteristics of the as-prepared samples have also been investigated.