A Comparative Study of Conventional Sintering with Microwave Sintering of High Dielectric Calcium Copper Titanate Nano Powder Synthesized by Sol-Gel Route

Abstract

Nano-sized calcium copper titanate (CCTO) powder was derived from sol-gel process. Calcium nitrate, copper nitrate and titanium iso-propoxide were used as raw materials. The XRD results of the powder calcined at 800°C indicated the formation of CCTO phase. AFM studies showed that the particle size of the CCTO powder ranged from 70 to 80 nm. The absorption bands corresponding to vibrations of Ca–O, Cu–O and Ti–O–Ti were observed at 606, 525 and 463 cm–¹ using FTIR. The samples sintered at 1040°C showed 96% of theoretical density. The dielectric constant of the sample sintered by conventional pressure less sintering was much higher (23,000 at 1 kHz) than that of microwave sintered samples (1572 at 1 kHz). In microwave sintering the grain boundary thickness decreases so that dielectric constant decreases.

Keywords:

• Sol-gel process
• Conventional sintering
• Microwave sintering
• Dielectric constant