| 摘要 |
The disclosure relates to fuel cell systems and methods for improving the operating efficiency and lifetime of fuel cells. In one aspect, the disclosure provides fuel cell systems including a fuel cell containing a fuel electrode, an oxidizer electrode, an electrolyte film between the fuel electrode and the oxidizer electrode, and a first catalyst layer including a first reversibly oxidized catalyst surface on a first catalyst support situated between the electrolyte film and the oxidizer electrode. In certain embodiments, the fuel cell system includes a second catalyst layer including a second reversibly oxidized catalyst surface on a second catalyst support situated between the electrolyte film and the fuel electrode. The disclosure also provides methods for operating a fuel cell in which an active catalyst surface is reversibly oxidized at the time of starting-up, shutting-down or altering the power output of the fuel cell by applying a voltage to the electrodes from a secondary energy storage cell such as a battery. The method may reduce irreversible degradation of a catalyst layer during fuel cell start-up, thereby improving fuel cell cycle stability and lifetime. |
