Significant enhancement in quality factor of Zn2TiO4 with Cu-substitution

✍ Scribed by Sandeep Butee; Ajit R. Kulkarni; Om Prakash; R.P.R.C. Aiyar; Ishan Wattamwar; Durgesh Bais; K. Sudheendran; K.C. James Raju

• Publisher: Elsevier Science
• Year: 2011
• Tongue: English
• Weight: 794 KB
• Volume: 176
• Category: Article
• ISSN: 0921-5107
• DOI: 10.1016/j.mseb.2011.01.013

✦ Synopsis

Zinc orthotitanate (Zn 1-x Cu x ) 2 TiO 4 , 0 ≤ x ≤ 0.20, spinel samples were prepared by solid state reaction and sintering. 1060 • C was the optimal sintering temperature for all the Cu-substituted samples which showed sintered density ≥94%, and maximum unloaded quality factor (Q u f). SEM microphotographs revealed fairly uniform grains between 2 and 20 m depending upon the composition. Microwave measurements at ∼7.1-7.5 GHz on these samples (as dielectric resonators) showed with Cu-substitution a steep increase in Q u f value from 2100 GHz (for Zn 2 TiO 4 , x = 0) to 15,200 GHz (for x = 0.10), a significant jump of over 7 times, while ε r was ∼20 (for x = 0) and ∼18 (x = 0.10). The jump in Q u f in Cu-substituted samples was attributed partly to improved sintered density and partly to absence of paramagnetic Ti 3+ , as revealed by electron spin resonance spectra at 9.1 GHz.