中文摘要：

采用三种碳粉制备了阴极扩散层，对其表面形貌、孔隙率、透水压和透气性进行了表征，并将其应用于空气自呼吸式直接甲醇燃料电池。结果表明，与VulcanXC-72R和BlackPearls2000碳粉所制备的阴极扩散层相比较。采用PrintexXE-2碳粉制备的阴极扩散层具有较高的孔隙率和适中的孔径，具有较高的透气性和较低的透水压。有利于阴极气体扩散和水的排出，提高了空气自呼吸式直接甲醇燃料电池的性能和极限电流密度。

英文摘要：

The effect of cathode gas diffusion layers （GDLs） on air-breath direct methanol fuel cell （ DMFC ）was studied. Three types of carbon powders （Vulcan XC-72R, Printex XE-2 and Black Pearls 2000） were used as cathode gas diffusion layers, which were characterized by N2 adsorption-desorption isotherms and scanning electron microscope （SEM）. The porosity, gas permeability and water permeation pressure of three GDLs were tested. It is shown that the Printex XE-2 GDL had the proper porosity and mass transport ability, which resulted in a higher cell performance than that of Vulcan XC-72R and Black Pearls 2000.