dc and ac Conductivities of (V2O5)x(B2O3)1−x oxide glasses

✍ Scribed by H. El Mkami; B. Deroide; R. Backov; J.V. Zanchetta

• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 200 KB
• Volume: 61
• Category: Article
• ISSN: 0022-3697
• DOI: 10.1016/s0022-3697(99)00306-6

✦ Synopsis

Glasses of composition (V 2 O 5 ) x (B 2 O 3 ) 1Ϫx with x 0:1; 0.3, 0.5, 0.7 and 0.9 were obtained by a quenching technique. Conductivity measurements using s ac were performed on compact pellets of these materials. The conductivity behavior in direct regime, s dc , is described by the "small polaron" model. The room temperature variation of log s dc with the activation energy of each composition, suggests an adiabatic hopping character to the conduction. Application of Hunt's model to describe the ac conductivity behavior shows that the relaxation process has a local character and can be described by hops between each pair of sites.