Disclosed are a highly durable electrolyte membrane having improved ion conductivity and a method of producing the same. The electrolyte membrane may include an ionomer having hydrogen ion conductivity and a complex dispersed in the ionomer. The complex may include: a support; a primary antioxidant loaded on the support and having radical scavenging ability; and a secondary antioxidant loaded on the support and having peroxide decomposition activity.

Disclosed herein are a method of manufacturing a fuel cell, and a fuel cell manufactured according to the method. The method includes bonding a sub-gasket, provided with an air inlet and a hydrogen inlet, to a side surface of a three-layer membrane-electrode assembly (MEA) including an electrolyte membrane, a cathode located on one surface of the electrolyte membrane, and an anode located on the other surface of the electrolyte membrane; stacking a gas diffusion layer, which comprises an antioxidant precursor, on at least one of the cathode and the anode and preparing a five-layer MEA; and applying a current to the five-layer MEA and moving an antioxidant, which is derived from the antioxidant precursor, to the electrolyte membrane.

Disclosed are an electrolyte membrane with improved ion conductivity and enhanced water transport and a method for manufacturing the same. The electrolyte membrane includes an ion transport layer including an ionomer having proton conductivity and a catalyst dispersed in the ion transport layer, and the catalyst includes a support including a shell configured to have a designated shape and size and to be hollow and at least one hole configured to allow an inner space to communicate with an outside therethrough, and a metal supported on the support.

Disclosed are an electrolyte membrane with improved ion conductivity and enhanced water transport and a method for manufacturing the same. The electrolyte membrane includes an ion transport layer including an ionomer having proton conductivity and a catalyst dispersed in the ion transport layer, and the catalyst includes a support including a shell configured to have a designated shape and size and to be hollow and at least one hole configured to allow an inner space to communicate with an outside therethrough, and a metal supported on the support.

Disclosed are an electrolyte membrane for fuel cells that can prevent poisoning of catalysts and a method of producing the same. The electrolyte membrane for fuel cells includes an ion transport layer including an ionomer having proton conductivity, and a catalytic composite dispersed in the ion transport layer, wherein the catalytic composite includes a catalytic particle including a catalytic metal component having an activity of decomposing hydrogen peroxide, and a protective layer formed on at least a part of a surface of the catalytic particle to prevent the ionomer from contacting the catalytic metal component.

Disclosed is an antioxidant for an electrolyte membrane of fuel cells. The antioxidant may include a support including silicon dioxide and having a nanotube shape, and a metal oxide supported on the support.

Disclosed is an antioxidant for an electrolyte membrane of fuel cells. The antioxidant may include a support including silicon dioxide and having a nanotube shape, and a metal oxide supported on the support.

Disclosed is an electrolyte membrane for a membrane-electrode assembly including a block copolymer composed of a hydrophilic domain and a hydrophobic domain.

Disclosed is an electrolyte membrane for a membrane-electrode assembly including a block copolymer composed of a hydrophilic domain and a hydrophobic domain.

Proton conductive membrane includes a proton selective layer of 80-100% carbon with sp2 hybridization having a thickness of 0.3-100 nm, with 0-20% of hydrogen, oxygen, nitrogen and sp3 carbon; wherein the sp2 carbon is in a form of graphene-like material; the proton selective layer having a plurality of pores formed by any of 7, 8, 9 or 10 sp2 carbon cycles or a combination thereof, with the pores having an effective diameter of up to 0.6 nm; an ionomeric polymer layer on the proton selective layer. Total thickness of the proton conductive membrane is less than 50 microns. The ionomeric polymer is PFSA (perfluorinated sulfonic acid), PVP (polyvinylpyrrolidone) or PVA (poly vinyl alcohol) with iodide or bromide counterion dissolved inside. The graphene-like material is CVD graphene or reduced graphene oxide (rGO). A D to G Raman band ratio of the membrane is more than 0.1.