助熔剂对无机质子导体BaZrO_3结构及形貌的影响

利用高温固相法制备了无机质子导体BaZrO3。研究了助熔剂的添加对材料的合成温度及微观形貌的影响。通过添加LiF及Li2CO3为助熔剂,可以在1500℃,保温8h合成很好的单相样品。且LiF为助熔剂制备样品的结晶性明显高于Li2CO3为助熔剂制备的样品。XRD精修表明所合成的样品为很好的单相样品。能带计算分析样品的带隙为3.236eV。通过加入LiF及Li2CO3为助熔剂,明显改善了样品的微观形貌,其中LiF为助熔剂样品的颗粒尺寸较小、团聚少,分散性好。当LiF及Li2CO3添加量为8%时,晶界处有小颗粒析出,这种小颗粒为提高材料的质子导电性提供了潜在的可能性。

Effect of flux on the structure and micro-morphology of inorganic proton conductor BaZrO3

The inorganic proton conductor BaZrO3 was prepared by high solid-state reaction. The effect of flux on the synthesis temperature and microstructure of the material was investigated. The BaZrO3 single phase can be synthesized at 1500 ℃ for 8 h by adding LiF and Li2CO3 as flux. The crystallinity of the sample which used LiF as flux was much higher than that of the sample which used Li2CO3 as flux. The Rietveld-XRD data showed that the sample had good crystallinity. The band gap of the sample was 3.236 eV. The micro-morphology was changed by adding the flux. The sample used LiF as flux had smaller particle size, fewer aggregations and good dispersion. The small particles were separated out at the grain boundary, when the mass fraction of the flux was more than 8%. These small particles had potential to increase the proton conductivity.