Atomic Layer Deposition of Platinum Catalyst in Hydrogen and Oxygen Proton Exchange Membrane Fuel Cell

• Main Authors: Chueh Liu, 劉玨
• Other Authors: Tsong-Pyng Perng
• Format: Others
• Language: en_US
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/58624758345545370151

碩士 === 國立清華大學 === 材料科學工程學系 === 95 === With the increasing threats of energy crisis and pollutions, fuel cell has become one of the most prospective substitute energies, but low catalyst activity and utilization results in high cost; however different preparation methods can change catalyst activity and utilization, so it’s expected atomic layer deposition can increase these two properties. Atomic layer deposition (ALD) is used to deposit Pt as catalyst of proton exchange membrane fuel cell catalyst on different substrates, including carbon cloth, carbon black powders or carbon nanotubes (CNT) coated on carbon cloth. In this experiment, Particle size is used to discuss self-limiting behavior and proportionality between particle size and cycle numbers of ALD of Pt on Si substrate. Both of the two characteristics are verified by SEM images. Substrate effects are also observed: Pt can not deposit on carbon cloth without acid treatment, and can not deposit on carbon black powder or CNT coated carbon cloth with higher concentration of PTFE addition; however, because of the change of the surface functional groups, for carbon cloth with acid treatment and carbon black powder or CNT coated carbon cloth with lower concentration of PTFE addition, Pt can deposit on them. Performance tests of different membrane electrode assemblies (MEAs) are compared. For the MEAs of the same anode and cathode, as received E-TEK electrode shows the largest power density (W/cm2), while the electrode of carbon cloth with ALD of Pt for 100 cycles has the lowest Pt specific power density (gPt/kW: gram of Pt per kilowattage). For the MEAs of different anodes but cathodes are all as received E-TEK electrodes, anode of ALD of Pt on CNT coated carbon cloth for 100 cycles shows the best Pt specific power density, while it still has similar power density to E-TEK electrode.