鑭鍶鈷鐵奈米纖維/銀顆粒複合陰極應用於質子傳輸型陶瓷電化學電池;LSCF Nanofiber/Ag Particle Composite Cathode for Proton-conducting Ceramic Electrochemical Cells

NCU Institutional Repository > 工學院 > 材料科學與工程研究所 > 博碩士論文 > Item 987654321/89433

jsp.display-item.identifier=請使用永久網址來引用或連結此文件: http://ir.lib.ncu.edu.tw/handle/987654321/89433

题名:	鑭鍶鈷鐵奈米纖維/銀顆粒複合陰極應用於質子傳輸型陶瓷電化學電池;LSCF Nanofiber/Ag Particle Composite Cathode for Proton-conducting Ceramic Electrochemical Cells
作者:	楊佳桂;Yang, Jia-Guei
贡献者:	材料科學與工程研究所
关键词:	銀;LSCF;奈米纖維;氧表面交換係數;複合陰極;穩定性;Ag;nanofiber;oxygen;surface exchange coefficient;complex cathode;stability
日期:	2022-09-26
上传时间:	2022-10-04 11:14:34 (UTC+8)
出版者:	國立中央大學
摘要:	質子傳導型陶瓷燃料電池(PCFC)在500-800℃範圍內運行會提高材料的耐久性，但同時也會降低空氣電極的氧還原反應(ORR)速率。陰極材料需具備高電子/離子之混合傳導性、較高的氧還原催化活性。此外，氣體容易擴散，可減少固體氧化物燃料電池（SOFC）中的極化損失。本研究中，我們通過靜電紡絲技術製備了La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF)奈米纖維，並添加銀漿配製成用於質子傳導型陶瓷燃料電池(PCFC)的複合陰極。銀具有良好的催化活性、高導電性，且為一種廉價的材料，但因銀顆粒在高溫下容易團聚，降低了陰極孔隙率，導致PCFC性能變差。本研究希望通過LSCF奈米纖維與銀形成複合陰極，LSCF奈米纖維來抑制銀顆粒在高溫下團聚情形，使電池性能提升。通過分析電池性能（I-V曲線）和電化學阻抗譜（EIS），我們可了解氣體、氧離子和電子在陰極傳輸的反應機制。其次，通過在復合陰極和電解質之間的界面中加入中間層可以改善電解質/陰極界面性能。可有效增加三相共存區(Triple phase boundary, TPB)點的密度。實驗結果表明，50wt%Ag-50wt%LSCF奈米纖維複合陰極性能最好，在800℃時的最大功率密度為445.37 mW/cm2，較低的歐姆阻抗和極化阻抗分別為1.737 Ω∙cm2和0.068 Ω∙cm2。通過24小時長期穩定性測試，衰減率僅為8%。故本研究結果可知，LSCF奈米纖維有效阻擋銀顆粒聚集，使陰極保持良好孔隙率，降低極化阻抗，同時銀顆粒具有良好催化活性對氧還原反應，提升氧還原反應速度。50wt%Ag-50wt%LSCF奈米纖維複合陰極提供質子傳導型陶瓷燃料電池裝置未來發展之潛力。 ;Operation of protonic ceramic fuel cell (PCFC) in the 500-800℃ range would enhance the durability of materials but also reduce the oxygen reduction reaction (ORR) rate at air electrode. The cathode material has high electronic/ionic mixed conductivity and has much greater electrocatalytic properties. Moreover, gas can easily diffuse to reduce the polarization loss in the solid oxide fuel cell (SOFC). In this study, we fabricate La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) nanofibers by electrospinning technique and then add silver slurry to form a complex material for protonic ceramic fuel cell (PCFC). Silver has a good catalytic activity, high electrical conductivity and is an inexpensive material, but silver particles can agglomerate easily at high temperature, which reduce the cathode porosity and result in poor PCFC performance. Therefore, we expect to improve the agglomeration of silver particles at high temperature by blending silver and LSCF nanofibers to form composite cathode. By analyzing cell performance (I-V curve) and electrochemical impedance spectroscopy (EIS), we can understand the reaction mechanism of gas, oxygen ions and electrons transport in the cathode. Secondly, by incorporating an interlayer into the interface between composite cathode and electrolyte can improves the electrolyte/cathode interfacial properties. It can effectively increase the density of triple phase points. The experimental results show that the 50wt%Ag–50wt%LSCF Fiber composite cathode has the best performance and shows the highest maximum power density of 445.37 mW/cm2 at 800℃, and the lower ohmic impedance and polarization impedance are 1.7370 Ω cm2 and 0.0683 Ω cm2, respectively. Besides, it only has a decay rate of 8% after 24 hours long-term stability test. From the results of this study, the LSCF nanofibers can effectively block the aggregation of silver particles, keep the cathode with good porosity, and reduce the polarization impedance. The 50wt%Ag-50wt%LSCF nanofiber composite cathode offers the potential for the future development of protonic ceramic fuel cell devices.
显示于类别:	[材料科學與工程研究所 ] 博碩士論文

文件中的档案:

档案	描述	大小	格式	浏览次数
index.html		0Kb	HTML	82	检视/开启

在NCUIR中所有的数据项都受到原著作权保护.

社群 sharing

数据加载中.....