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W. Tillmetz 《化学,工程师,技术》2003,75(8):1087-1087
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Ashish Kamat Dr. Olaf Klein Dr. Mirko Herrmann Jun.‐Prof. Dr.‐Ing. Ulrike Krewer Prof. Dr.‐Ing. Stephan Scholl 《化学,工程师,技术》2012,84(12):2198-2203
During thermal cycling investigations on polybenzimidazole high temperature polymer electrolyte membrane fuel cells a stationary hysteresis behavior of the cell current was observed. With the Tafel equation a correlation to the surface oxygen concentration on the platinum is given. Because no such hysteresis of oxygen adsorption on platinum is known a new theory is proposed. This theory is based on the thermal dependence of the surface coverage of phosphoric acid on platinum. The resulting adsorption hysteresis is confirmed as being the reason for the observed cell current hysteresis by the results of a Monte Carlo simulation. This is validated through a qualitative comparison with measured data from aged test cells. 相似文献
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Gas flow sputtering (GFS) at increased pressures results in the formation of nanoscale particles of the sputtered material. This process has been evaluated regarding its applicability for synthesizing Pt catalysts for polymer electrolyte membrane fuel cells (PEMFCs). Catalyst layers of varying Pt‐loadings were deposited directly onto carbon fiber paper (gas diffusion layers, GDLs). Immediately after deposition, the catalytic activity of the resulting particulate deposits was tested by H2‐oxidation at predefined ratios of H2/O2. The Pt deposits were subsequently evaluated regarding their applicability in a PEMFC environment. 相似文献
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