Titanium nitride (TiN)–polytetrafluoroethylene (PTFE)-modified carbon paper used in PEM fuel cells: characterization and corrosion-resistant mechanism

Titanium nitride (TiN) nanoparticles (NPs) were added into polytetrafluoroethylene (PTFE) emulsion for the hydrophobic treatment of carbon papers (CPs). The addition of the nano-sized conducting nanoparticles in impregnation solution could improve the corrosion resistance, electrical conductivity, hydrophobicity and durability of the treated CPs. It is found that the corrosion resistance and electrical conductivity of the as-treated CPs increased gradually as the increment of TiN content. CPs impregnated with PTFE emulsion containing 8 wt% TiN NPs displayed the optimal improved corrosion resistance with corrosion potential and corrosion current density at 0.16 V and 0.056 μA/cm 2 , respectively. Characterizations by SEM, Raman and XPS demonstrate that this improvement is associated with the formation of TiN coating and the improved distribution of PTFE on CPs.