Microwave hall mobility studies on polymer–metal oxide nanocomposites

✍ Scribed by D. V. B. Murthy; V. Subramanian; V. S. Pavan Kumar; T. S. Natarajan; G. K. Raghuraman; R. Dhamodharan; V. R. K. Murthy

• Book ID: 101594061
• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 185 KB
• Volume: 107
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/app.27240

✦ Synopsis

Abstract

Films of polymer metal oxide composites with poly(methyl methacrylate) and metallic powders (CuO, Ni, and brushed Fe~3~O~4~) were prepared with a spin‐casting method. Electric transport studies indicated that the compositions surpassed the percolation threshold limit. Alternating current (AC) conductivity studies confirmed a hopping mechanism with power‐law behavior in frequency. For the first time, the mobility values of the carriers in these films were measured by the contactless microwave Hall effect technique with a bimodal cavity operating at 14 GHz. In this technique, a circular bimodal cavity is used to measure the change in the transmission coefficient (proportional to the carrier mobility) due to the application of a static magnetic field perpendicular to the microwave electric fields. The mobility measurements indicated a decrease in mobility with increasing quantity of CuO and Ni and showed an increase in the carrier–lattice scattering, whereas the mobility increased with increasing Fe~3~O~4~ due to the negative magneto resistance. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008