Improved durability of Pt/CNT catalysts by the low temperature self-catalyzed reduction for the PEM fuel cells

Long-term durability of catalysts is considered as the most critical issue to commercialize the fuel cell vehicles. In this study, we showed highly durable CNT-supported Pt catalysts treated by simple low temperature hydrogen bubbling (LTHB). Even at low temperature, the loss of the oxygen related functional groups which can accelerate the carbon corrosion and Pt agglomeration was observed by the effect of the catalytic cleavage of hydrogen molecules followed by the spillover and dehydration reaction. The 62.5% activity loss was observed in the commercial Pt/C catalyst but only 6.2% for Pt/CNT-R catalyst after high voltage acceleration test. Less agglomeration of Pt particles and loss of active surface area were observed than those of commercial Pt/C catalysts, which also contributed to the less increase in the electrochemical resistance of PT/CNT-R. The polarization resistance increased only 3% for Pt/CNT-R but as high as 700% for commercial Pt/C.

► Highly durable Pt/CNT was fabricated by low temperature hydrogen bubbling.
► Functional groups were removed by the self-catalyzed reduction reaction.
► Weakly bond Pt particles were effectively removed prior to be used in fuel cell.
► Pt agglomeration was restrained even after high voltage acceleration test.