質子交換膜燃料電池陰極觸媒層之最適化

Study on the optimum composition in the cathode catalyst layer of the Proton Exchange Membrane Fuel Cell

湯誌畯(Chih-Chun Tang)

指導教授 ： 尹庚鳴

元智大學/工程學院/化學工程與材料科學學系/碩士(2004年)

摘要

本研究專注於質子交換膜燃料電池的陰極電化學特性，而性能優越的氣體擴散電極必須兼具有疏水性與親水性的特性，提供觸媒、電解質、水、黏結劑和氣體反應物在三相反應區所必須有的活性位置與氣體和液體的填充空間。因此本研究目標在於利用電化學的分析方式試圖找出質子交換膜燃料電池陰極觸媒層中固態電解質（Nafion，利於離子傳導至觸媒層中的活性位置）與黏結劑（PTFE，作為疏水劑）之間最佳組合。
本研究將固定觸媒層中白金用量（Pt loading：0.4 mg/cm2），實驗在常壓下進行，設定系統操作溫度於60℃、氧氣流量為65sccm（Standard Cubic Centimeter per Minute）以及氮氣流量為100sccm。針對利用塗佈法或轉印法所製作之MEA來進行電化學半反應測試，經電化學測試分析可得在上述之條件下，使用塗佈法來製作的MEA，無論觸媒是使用10wt%-Pt/C或是20wt%-Pt/C，其觸媒層中Pt/C：Nafion＝1：0.75時其電池效能表現最佳。而使用轉印法所製作的MEA，可看出當觸媒層中PTFE含量為5wt%、Pt/C：Nafion＝1：0.05時電池效能表現較佳。

關鍵字

陰極 ； 觸媒層 ； 質子交換膜燃料電池

並列摘要

This study focuses on the electrochemical characteristics of the proton exchange membrane fuel cell cathode. The Gas diffusion Electrode with good performance should combine the hydrophobic and hydrophilic properties. The gas diffusion electrode should have enough active sites, which give enough space for the gas and liquid to fill in the three phase reaction region. Electrochemical analysis method was to determine the optimal composition of solid ionomer and binder used in the catalyst layer of a PEMFC cathode.
Platinum loading employed in this study was fixed at 0.4 mg/cm2. The electrochemical measurements were carried out at 60℃ in a half cell, with O2 flow rate at 65 sccm and N2 flow rate at 100 sccm. For the electrodes prepared by brush method, the best cell performance was Pt/C : Nafion =1 : 0.75 in the catalyst layer. For the electrodes prepared by filtration method, best cell performance was obtained at 5wt%-PTFE and Pt/C : Nafion =1 : 0.05 .

並列關鍵字

cathode ； catalyst layer ； PEMFC

參考文獻

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