摘要
Plasma sputtering deposition techniques are good candidates for the fabrication of electrodes used for direct methanol fuel cells (DMFCs). A house-made plasma sputtering system was used to deposit platinum of 0.1 mg/cm^2 onto un-catalyzed gas diffusion layers (GDLs) to form a Pt catalyzed cathode at different radio frequency (RF) powers and sputtering-gas pressures. The sputtered cathodes were assembled in custom-made membrane electrode assemblies (MEAs) with a commercial anode and tested for the electrical performance of the single cell. A custommade MEA with a sputtering prepared cathode was compared with that of a reference membrane electrode assembly made of commercial JM (Johnson Mattey) catalysts (Pt loading per electrode of 0.5 mg/cm^2) under passive methanol supply, ambient temperature and air-breathing conditions. The results showed that the cathode prepared at an input power of 110 W and sputtering-gas pressure of 5.3 Pa exhibited the best cell performance and highest Pt utilization efficiency, which was due to the miniaturization of the Pt particles and formation of the porous catalyst layer. Although the single cell performance of the commercial cathode was better than all the sputtering fabricated cathodes, the Pt utilization efficiency of all the sputtered cathodes was higher than that of the commercial cathode.
Plasma sputtering deposition techniques are good candidates for the fabrication of electrodes used for direct methanol fuel cells (DMFCs). A house-made plasma sputtering system was used to deposit platinum of 0.1 mg/cm^2 onto un-catalyzed gas diffusion layers (GDLs) to form a Pt catalyzed cathode at different radio frequency (RF) powers and sputtering-gas pressures. The sputtered cathodes were assembled in custom-made membrane electrode assemblies (MEAs) with a commercial anode and tested for the electrical performance of the single cell. A custommade MEA with a sputtering prepared cathode was compared with that of a reference membrane electrode assembly made of commercial JM (Johnson Mattey) catalysts (Pt loading per electrode of 0.5 mg/cm^2) under passive methanol supply, ambient temperature and air-breathing conditions. The results showed that the cathode prepared at an input power of 110 W and sputtering-gas pressure of 5.3 Pa exhibited the best cell performance and highest Pt utilization efficiency, which was due to the miniaturization of the Pt particles and formation of the porous catalyst layer. Although the single cell performance of the commercial cathode was better than all the sputtering fabricated cathodes, the Pt utilization efficiency of all the sputtered cathodes was higher than that of the commercial cathode.
基金
supported by National Natural Science Foundation of China (No. 10975162)
the Principal Foundation of Institute of Plasma Physics
Chinese Academy of Sciences (No. 095GZ1156Y)