Porous medium with increased hydrophobicity and method of manufacturing the same

摘要

The present invention provides a porous medium with increased hydrophobicity and a method of manufacturing the same, in which a micro-nano dual structure is provided by forming nanoprotrusions with a high aspect ratio by performing plasma etching on the surface of a porous medium with a micrometer-scale surface roughness and a hydrophobic thin film is deposited on the surface of the micro-nano dual structure, thus significantly increasing hydrophobicity. When this highly hydrophobic porous medium is used as a gas diffusion layer of a fuel cell, it is possible to efficiently discharge water produced during electrochemical reaction of the fuel cell, thus preventing flooding in the fuel cell. Moreover, it is possible to sufficiently supply reactant gases such as hydrogen and air (oxygen) to a membrane electrode assembly (MEA), thus improving the performance of the fuel cell.

主权项

1. A method of manufacturing a porous medium with increased hydrophobicity, the method comprising:
providing a porous medium having a micrometer-scale-roughness surface wherein the porous medium includes a macroporous substrate containing carbon fibers and a microporous layer containing carbon particles; forming a micro-nano dual structure on the surface of the porous medium by forming nanometer-scale protrusions and/or nanometer-scale collapsed pores on the micrometer-scale-roughness surface by performing plasma etching on the micrometer-scale-roughness surface, wherein the plasma etching is carried out on both surfaces of the macroporous substrate and the surface of the microporous layer to form the micro-nano dual structure in which the nanometer-scale protrusions and/or nanometer-scale collapsed pores are formed within surfaces of the carbon particles and/or within surfaces of the carbon fibers; and depositing a hydrophobic thin film on the surface of the micro-nano dual structure.