Promotion of oxygen reduction reaction durability of carbon-supported PtAu catalysts by surface segregation and TiO₂ addition.
Highly effective carbon supported-Pt75Au25 catalysts for oxygen reduction reaction (ORR) are prepared though titanium dioxide modification and post heat treatment. After accelerated durability test (ADT) of 1700 cycles, the ORR activity of PtAu/C catalysts modified by TiO2 and air heat treatment is 3 times higher than that of the commercial Pt/C. The enhancement of ORR activity is attributed to surface and structural alteration by air-induced Pt surface segregation and lower unfilled d states. On the contrary, for TiO2 modified and H2 treated PtAu/C catalysts, the deterioration of the ORR activity may be due to the loss of electrochemical surface area after ADT and the increase of d-band vacancy.
Institute of Materials Science and Engineering, National Central University , Taoyuan 320, Taiwan.
Chen-Wei
CW
Liu
Hong-Shuo
HS
Chen
Chien-Ming
CM
Lai
Jiunn-Nan
JN
Lin
Li-Duan
LD
Tsai
Kuan-Wen
KW
Wang