Self-assembled Nafion
x2013;SiO
2 polymer electrolyte membrane enhanced by ePTFE matrix was prepared in this study. The original ePTFE membrane was chemically modified before the preparation by sodium
x2013;naphthalene treatment to increase the wetting compatibility between self-assembled Nafion
x2013;SiO
2 dispersions and ePTFE matrix. Compared to the freestanding Nafion
x2013;SiO
2 membrane, the physical strength of the as-resulting ePTFE PEM was significantly improved from
20 MPa to 32 MPa. The area conductance of the as-resulting membrane was also promoted to
40 S cm
−2 and
50 S cm
−2, respectively at 60 °C and 100 °C with the decrease of the membrane thickness (15 μm) in 50%RH gas atmosphere. With the presence of self-assembled silica particles, the self-assembled Nafion
x2013;SiO
2x2013;ePTFE composite membrane possesses excellent
water-retention property. At elevated operating temperature of 100 °C, 50%RH, 0 back pressure, the output voltage of the Nafion
x2013;SiO
2x2013;ePTFE fuel cell was 0.603 V under condition of 600 mA cm
−2, 0.105 V higher than that of the freestanding Nafion/ePTFE fuel cell under the same condition.