Membrane-electrode assembly, method for manufacturing same, and fuel cell comprising same

A membrane-electrode assembly comprising:

• an ion exchange membrane;
• first and second catalyst layers, the ion exchange membrane being disposed between the first and second catalyst layers;
• a first functional modification layer between the first catalyst layer and the ion exchange membrane;
• and
• a second functional modification layer between the second catalyst layer and the ion exchange membrane,
• wherein each of the first and second functional modification layers comprises an ionomer,
• wherein SiO2 nanoparticles substituted with a sulfonic acid group are included in both the first and second functional modification layers but not in the ion exchange membrance interposed between the first and second functional modification layers,
• wherein the SiO2 nanoparticles have a particle diameter of 1 nm to 100 nm,
• wherein each of the first and second functional modification layers comprises 0.1 wt % to 30 wt % of the SiO2 nanoparticles based on a total weight thereof, and
• wherein each of the first and second funcational modificiation layers has a thickness of 10 nm to 3 μm.