An Studying on the Synthesis and Densification Behavior of β''- Alumina Electrolyte for Sodium-Sulfur Batteries

Subject Areas : journal of New Materials

هاجر Ahmadi Moghadam ¹ (دانشجوی دکتری بخش مهندسی مواد دانشگاه شیراز.)
M. H Paaydar ² (استاد، هیئت علمی بخش مهندسی مواد دانشگاه شیراز.)

Received: 2016-05-20 Accepted : 2016-05-20 Published : 2015-12-22

Keywords: Microstructure, β''- Alumina, Zeta Process, Sintering, Synthesize,

Abstract :

β''-Alumina electrolyte as a sodium ion conductor is used in sodium sulfur batteries. To obtain the appropriate ionic conductivity, this electrolyte should gain high density and uniform microstructure during manufacturing process. For this purpose, in the present work, β''-alumina powder was synthesized and the parameters influencing the densification behavior of β''-alumina ceramic have been studied. β''- alumina powder synthesized by the zeta process and the raw samples were formed by uniaxial pressing and sintered at different temperatures and for different times. The phase identification of the synthesized powder and fabricated electrolyte was performed by X-ray diffraction (XRD), scanning electron microscopy and measuring of density were used to investigate the densification behavior. The results showed that the microstructure of the β''-alumina ceramics strongly depends on the sintering conditions.Decreasing in the density and the duplex microstructure occurred with increasing the time of the sintering. The optimum condition for the sinte ring of the β''- alumina electrolyte was determined to be at 1620 ºC for 15 min, which results in a dense sample with more than 99% of theoretical density, uniform microstructure, without excessive grain growth and the lack of duplex microstructure including more than 99 percent β''-Al₂O₃ phase.

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