1. Schematic diagram of PEMFC^[6]

2. Degradation schematic diagram of Pt nanoparticles on carbon black^[21]

3. AFM images of high oriented polyrotic graphite surface before (a) and after (b) electrochemical corrosion^[27]

4. FESEM micrographs of carbon aerogel samples CA20(a), CA30(b) and CA40(c) ^[28]

5. Pore size distribution curves(a) of carbon aerogels determined by mercury porosimetry with different molar ratios of resorcinol (R) and sodium carbonate (C), and their corresponding single cell polarization curves(b)^[29]

6. TEM images after accelerated stress tests (AST P1) and Pt nanoparticles statistical distributions before and after accelerated stress tests (AST P1)of carbon aerogels (a), SnO₂ coated carbon aerogels (b) supported Pt catalysts^[36]

7. Schematic illustrations of the structures(a-c), tunneling electron microscope image(d), transmission electron microscope image (e) of carbon nanotubes^[38]

8. PEMFC polarization curves recorded after accelerated stress tests with cathode catalysts of commercial Pt/carbon black (a) and Pt/carbon black-graphene hybrid material (b); Voltage retention normalized with respect to initial performance after 10, 20, 100, 200, 500, and 1000 cycles(c)^[55]