本文選題：中低溫固體氧化物燃料電池　切入點(diǎn)：電解質(zhì)薄膜　出處：《大連理工大學(xué)》2010年碩士論文　論文類(lèi)型：學(xué)位論文

【摘要】： 固體氧化物燃料電池(SOFCs)是一種直接將儲(chǔ)存在燃料和氧化劑中的化學(xué)能高效、環(huán)境友好地轉(zhuǎn)化成電能的全固態(tài)化學(xué)發(fā)電裝置。目前,SOFCs的發(fā)展趨勢(shì)是中低溫化。降低SOFCs運(yùn)行溫度的方法有：(1)電解質(zhì)材料的薄膜化,(2)使用中低溫下具有高電導(dǎo)率的電解質(zhì)。磷灰石型硅酸鑭因?yàn)榫哂懈叩闹械蜏仉妼?dǎo)率,高的化學(xué)穩(wěn)定性等優(yōu)點(diǎn)而成為中低溫固體氧化物燃料電池電解質(zhì)的研究熱點(diǎn)。磷灰石型硅酸鑭一般采用固相反應(yīng)法制備,但制備的磷灰石型硅酸鑭存在的問(wèn)題是燒結(jié)溫度高和不易致密。采用磁控濺射法制備磷灰石型硅酸鑭電解質(zhì)薄膜有望解決在較低溫度下制備的磷灰石型硅酸鑭電解質(zhì)很難致密的難題。而且電解質(zhì)的薄膜化能降低其內(nèi)阻,進(jìn)一步降低SOFCs的運(yùn)行溫度。 本文首先采用固相反應(yīng)法制備磷灰石型硅酸鑭陶瓷靶材。使用精密天平,游標(biāo)卡尺測(cè)量靶材的重量和尺寸,根據(jù)公式計(jì)算確定靶材致密度。采用XRD, SEM等測(cè)試方法表征了靶材的物相組成,表面形貌。實(shí)驗(yàn)結(jié)果表明,在1560℃下燒結(jié),靶材的致密度為73.9%,靶材中主要是磷灰石相(La9.33Si6O26)；在1620℃下燒結(jié)靶材的致密度為83.5%,靶材主要相也為磷灰石相(La9.33Si6O26)。 使用磷灰石型硅酸鑭靶磁控濺射制備磷灰石型硅酸鑭電解質(zhì)薄膜。首先實(shí)驗(yàn)中只使用磷灰石型硅酸鑭單靶,制備的電解質(zhì)薄膜中存在的問(wèn)題是La含量嚴(yán)重不足。造成這種現(xiàn)象的原因?yàn)椋?1)靶材中La成分不足；(2)La的濺射產(chǎn)額低。所以使用磷灰石型硅酸鑭靶和鑭靶共濺射制備磷灰石型硅酸鑭電解質(zhì)薄膜。磷灰石型硅酸鑭靶采用射頻濺射,鑭靶采用直流濺射。通過(guò)EPMA,SEM,臺(tái)階儀等測(cè)試方法分別測(cè)量電解質(zhì)薄膜的成分、表面形貌、薄膜厚度。實(shí)驗(yàn)結(jié)果表明,最佳的實(shí)驗(yàn)參數(shù)為：射頻功率100W,直流功率11W,工作氣壓0.8Pa,偏壓-45V。制備的電解質(zhì)薄膜中最好成分為L(zhǎng)a 70.060wt%,Si 7.530wt%,Mg 0.063wt%,O 22.349wt%,La：Si摩爾比為10：5.32。電解質(zhì)薄膜連續(xù)且致密。電解質(zhì)薄膜的厚度為3μm-4μm,沉積速率為400nm／h-500 nm／h。 磁控濺射制備的電解質(zhì)薄膜需退火以獲得磷灰石相。通過(guò)XRD表征退火后電解質(zhì)薄膜中的物相。結(jié)果表明,在1100℃下退火5h后,電解質(zhì)薄膜中磷灰石(La9.33Si6O26)相的含量最多。另外,所有退火后的電解質(zhì)薄膜中還含有La2Si207相和La2SiO5相。
[Abstract]:Solid oxide fuel cell (SOFCs) is a chemical energy that is stored directly in fuels and oxidants. An environmentally friendly all solid state chemical power plant that converts electricity into electrical energy. The current trend of development of SOFCs is moderate and low temperature. The method to reduce the operating temperature of SOFCs is: 1) thin film of electrolyte material, 2) use of medium and low temperature with high conductivity. Electrolytes. Apatite type lanthanum silicate, due to its high electrical conductivity at moderate and low temperatures, Because of its high chemical stability, lanthanum silicate is usually prepared by solid state reaction. However, the problems existed in the preparation of apatite type lanthanum silicate are that the sintering temperature is high and it is not easy to compact. The preparation of apatite type lanthanum silicate electrolyte film by magnetron sputtering is expected to solve the problem of apatite type lanthanum silicate electrolysis prepared at lower temperature. It is difficult to solve the problem of dense quality, and the thin film of electrolyte can reduce its internal resistance. Further reduce the operating temperature of SOFCs. In this paper, the apatite type lanthanum silicate ceramic target was prepared by solid state reaction method. The weight and size of the target were measured by using precision balance and Vernier caliper. According to the formula calculation, the target density was determined. The phase composition and surface morphology of the target were characterized by XRD, SEM, etc. The experimental results showed that the target was sintered at 1560 鈩，

本文編號(hào)：1643720