發(fā)布時(shí)間：2018-03-05 13:34

  本文選題：鈣鈦礦結(jié)構(gòu)材料　切入點(diǎn)：Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ)　出處：《合肥工業(yè)大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：鈣鈦礦型陶瓷材料具有良好的催化活性,電化學(xué)特性等,在純氧生產(chǎn)、電池電極材料,以及化工催化領(lǐng)域都有著良好的應(yīng)用前景。對(duì)于面向?qū)嶋H應(yīng)用的透氧膜材料來說,提高膜材料的透氧量和解決低氧分壓氣氛中膜穩(wěn)定性等是其實(shí)現(xiàn)工業(yè)化應(yīng)用的關(guān)鍵。為此,需解決提高材料的透氧量和性能穩(wěn)定性等問題。影響陶瓷膜性能的因素較多,例如膜材料的組成、微觀結(jié)構(gòu),膜的表面修飾等。本論文對(duì)Ba0.5Sr0.5Co0.8Fe0.2O3-δ陶瓷膜的制備工藝、微觀結(jié)構(gòu)及性能等進(jìn)行研究,并考察表面修飾對(duì)Ba0.5Sr0.5Co0.8Fe0.2O3-δ膜材料的透氧性能的影響,此外,還考察了Sc和Cr摻雜對(duì)BaFeO3材料電性能和透氧性能等的影響,以探索新型的無Co透氧膜材料的制備。全文所得主要結(jié)論如下：(1) 通過甘氨酸-硝酸鹽法,在900℃以上煅燒前驅(qū)體粉末,可以獲得具有鈣鈦礦結(jié)構(gòu)的BaFeO3粉體。并在不同的溫度下燒結(jié)制備了燒結(jié)體材料,測(cè)得1000℃、1050℃和1100℃燒結(jié)所得燒結(jié)體在900℃的透氧量分別為0.81 ml·cm-2·min-1、1.13 ml·cm-2·min-1和1.56 ml·cm-2·min-1。1000℃、1050℃和1100℃燒結(jié)所得Ba0.5Sr0.5Co0.8Fe0.2O3-δ燒結(jié)體在400-800℃的平均熱膨脹系數(shù)分別為14.34×10-6K-1,15.46x10-6K-1,15.34×10-6K-1。(2) 通過硝酸浸蝕對(duì)BSCF透氧膜表面進(jìn)行修飾處理,使膜表面由原來的致密狀態(tài)變得粗糙不平,增加了膜的比表面積,有利于表面氧交換反應(yīng)的進(jìn)行。且發(fā)現(xiàn)延長硝酸浸蝕時(shí)間會(huì)加強(qiáng)酸蝕的反應(yīng),膜表面會(huì)變得更加粗糙不平。對(duì)表面修飾過膜片的透氧率測(cè)試表明,經(jīng)硝酸浸蝕20min后膜片的透氧量提高了1.6-4.5倍,而經(jīng)硝酸浸蝕10min后膜片的透氧量提高了1.4-3.8倍,這可能是由于膜表面的粗糙水平不同造成。(3) 采用甘氨酸-硝酸鹽法制備了BaFe1-yNyO3-δ(N=Sc、Cr, y=0、0.05、0.1、0.15)粉體,并制備相應(yīng)的透氧膜材料。XRD表明,BaFeO3-δ材料在室溫下是六方相,少量Sc的摻雜可使材料在室溫下轉(zhuǎn)變?yōu)榱⒎浇Y(jié)構(gòu),少量Cr的摻雜也促進(jìn)BaFeO3-δ氧化物在室溫下轉(zhuǎn)變?yōu)榱⒎较�。電�?dǎo)率和透氧量的測(cè)試結(jié)果表明,少量Sc和Cr的摻雜會(huì)提高BaFeO3-δ的電導(dǎo)率和透氧量。BaFe0.95Sc0.05O3-□在450℃時(shí)電導(dǎo)率可達(dá)7.2S-cm-1,約是BaFeO3-δ材料的60倍; BaFe0.95Cr0.05O3-δ在450℃時(shí)電導(dǎo)率最大值分別為4.8 s·cm-1,約是BaFeO3-δ材料的40倍；且BaFe0.95Sc0.05O3-δ具有最大的透氧量,在900℃時(shí)達(dá)到0.66 ml·cm-2·min-1。
[Abstract]:Perovskite ceramic materials have good catalytic activity and electrochemical characteristics, and have a good application prospect in pure oxygen production, battery electrode materials and chemical catalytic field. Improving the oxygen permeability of membrane materials and solving the stability of membrane in low oxygen partial pressure atmosphere are the key to realize the industrial application. Therefore, it is necessary to solve the problems such as improving the oxygen permeability and property stability of the materials. There are many factors that affect the properties of ceramic membranes. For example, the composition, microstructure and surface modification of Ba0.5Sr0.5Co0.8Fe0.2O3- 未 ceramic films were studied in this paper. The effects of surface modification on the oxygen permeability of Ba0.5Sr0.5Co0.8Fe0.2O3- 未 films were investigated. The effects of SC and Cr doping on the electrical properties and oxygen permeability of BaFeO3 materials were also investigated in order to explore the preparation of new Co free oxygen permeable membrane materials. The main conclusions obtained in this paper are as follows: 1) by glycine nitrate method. The BaFeO3 powder with perovskite structure can be obtained by calcining the precursor powder above 900 鈩，

本文編號(hào)：1570478