Conductivity studies on microwave synthesized glasses

Bulletin of materials science

Asha Rajiv¹  M Sudhakara Reddy¹  C Narayana Reddy³  R Viswanatha²  Jayagopal Uchil¹ 

[1] Department of Physics, School of Graduate Studies, Jain University, Bangalore 560027, India$$Department of Physics, School of Graduate Studies, Jain University, Bangalore 560027, IndiaDepartment of Physics, School of Graduate Studies, Jain University, Bangalore 560027, India$$;Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India$$Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, IndiaSolid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India$$;Department of Physics, Sree Siddaganga College of Arts, Science and Commerce, Tumkur University, Tumkur 572103, India$$Department of Physics, Sree Siddaganga College of Arts, Science and Commerce, Tumkur University, Tumkur 572103, IndiaDepartment of Physics, Sree Siddaganga College of Arts, Science and Commerce, Tumkur University, Tumkur 572103, India$$

关键词: Conductivity;    electrical modulus;    impedance;    microwave;    power law;    stretched exponent.;   

DOI  :  

学科分类：材料工程

来源: Indian Academy of Sciences

【 摘 要 】

Conductivity measurements have been made on 𝑥ð�?��??₂O₅ âˆ�? (100 âˆ�? ð‘�?) [0.5 Na₂O + 0.5 B₂O₃] (where 10 â‰�? ð‘�? â‰�? 50) glasses prepared by using microwave method. DC conductivity (𝜎) measurements exhibit temperature-and compositional-dependent trends. It has been found that conductivity in these glasses changes from the predominantly ‘ionic’ to predominantly ‘electronic’ depending upon the chemical composition. The dc conductivity passes through a deep minimum, which is attributed to network disruption. Also, this nonlinear variation in 𝜎_dc and activation energy can be interpreted using ionâ€�?�polaron correlation effect. Electron paramagnetic resonance (EPR) and impedance spectroscopic techniques have been used to elucidate the nature of conduction mechanism. The EPR spectra reveals, in least modified (25 Na₂O mol%) glasses, conduction is due to the transfer of electrons via aliovalent vanadium sites, while in highly modified (45 Na₂O mol%) glasses Na⁺ ion transport dominates the electrical conduction. For highly modified glasses, frequency-dependent conductivity has been analysed using electrical modulus formalism and the observations have been discussed.

【 授权许可】

Unknown