Abstract: Provided is a gas diffusion layer, in which a microporous layer has an inner wall of through passages and a region adjacent to the through passages containing a greater amount of a water-repellent binder resin than a region not adjacent to the through passages, and thus water formed by an electrochemical reaction is effectively discharged from the gas diffusion layer. When the gas diffusion layer of the present invention is used, an optimal water management may be possible for smooth operation under all humidity conditions including a high humidity condition and a low humidity condition, and thus a fuel cell having improved cell performance may be obtained.

Abstract: Disclosed are a carbon substrate for a gas diffusion layer of a fuel cell, a gas diffusion layer employing the same, an electrode for a fuel cell, a membrane electrode assembly for a fuel cell, and a fuel cell, wherein the carbon substrate includes a plate-shaped substrate having an upper surface and a lower surface opposite the upper surface, and the plate-shaped substrate includes carbon fibers arranged to extend in one direction (extend unidirectionally) and a carbide of an organic polymer located between the carbon fibers to bind the carbon fibers to each other.

Abstract: A carbon substrate for a gas diffusion layer of a fuel cell, the carbon substrate being a porous carbon substrate having a first surface and a second surface opposite the first surface, the carbon substrate includes a plurality of carbon fibers arranged irregularly to form a non-woven type and a carbide of an organic polymer located between the carbon fibers to bind the carbon fibers to each other, the carbide has a graphite structure, and the carbon substrate has a Bragg diffraction angle 2? of less than 26.435° and a interplanar distance d(002) of less than 3.372 ?, a gas diffusion layer employing the same, an electrode for a fuel cell, a membrane electrode assembly for a fuel cell, and a fuel cell. When the gas diffusion layer is manufactured using the carbon substrate according to the present disclosure, cell voltage characteristics of the fuel cell may be greatly improved.

Abstract: Provided is a carbon substrate for a gas diffusion layer of a fuel cell. The carbon substrate has a structure, in which a plurality of unit carbon substrates are stacked. Each of the unit carbon substrates is a plate type substrate having a first surface and a second surface opposite to the first surface. Carbon fibers are randomly arranged on the first surface of the each unit carbon substrate. The number of the carbon fibers arranged in a machine direction of the unit carbon substrate is greater than the number of carbon fibers arranged in a transverse direction of the unit carbon substrate from the first surface to the second surface along a thickness direction of the unit carbon substrate; and, accordingly, an orientation gradient, in which the orientation in the machine direction increases from the first surface to the second surface, is shown.

Abstract: A carbon substrate for a gas diffusion layer that has a porosity gradient in a thickness direction thereof, a gas diffusion using the carbon substrate, an electrode and a membrane-electrode assembly for a fuel cell that include the gas diffusion layer, and a fuel cell including the membrane-electrode assembly having the gas diffusion layer are provided. The gas diffusion layer has improved water discharge ability and improved bending strength both in the machine direction and cross-machine direction.

Abstract: A carbon substrate for a gas diffusion layer that has a porosity gradient in a thickness direction thereof, a gas diffusion using the carbon substrate, an electrode and a membrane-electrode assembly for a fuel cell that include the gas diffusion layer, and a fuel cell including the membrane-electrode assembly having the gas diffusion layer are provided. The gas diffusion layer has improved water discharge ability and improved bending strength both in the machine direction and cross-machine direction.