| 초록 |
Oxygen reduction reaction (ORR) is one of the most important electrochemical reactions occurring in the cathodic compartment of fuel cells. As a candidate support materials, TiO2 has attracted consideration as a novel support material due to the stability in fuel cell operation condition and the ease of controlling its shape and structure. Doping Nb dopant whose atomic radius is similar to that of Ti may increase the electrical conductivity of TiO2. We synthesized nanotube and nanowhisker shapes of TiO2 using the hydrothermal process. Doping Nb into the TiO2 leads to a drastic increase in electrical conductivity with doping level of up to 25 at%. Pt nanoparticles are synthesized by impregnation method. Then, the nanoparticles were characterized by XRD, SEM, and TEM. Electrochemical experiments were performed in a conventional three-electrode cell. The electrocatalytic activity and durability of the synthesized nanocatalysts were compared with commercial carbon black during an accelerated stress test. We think that the excellent activities of the Pt/Nb-TiO2 catalysts are attributed to high corrosion resistance of TiO2 and strong interaction between Pt and TiO2. |
