Functional rGO supported porous PdAg nanospheres self-intercalation catalysts with high stability for direct ethanol fuel cell

Abstract

The poor long-term stability of anodic catalysts is one of the important factors that hinder the commercial application of direct ethanol fuel cells. The main reason is that toxic intermediates (such as CO) produced in the process of ethanol oxidation are easy to cover the active site, resulting in the catalyst being poisoned and deactivated in a short time. In this work, the prepared catalysts by the co-reduction method use didecyldimethylammonium chloride (DODAC) as the structure directing agent. The PdAg microporous alloy nanospheres in situ growth can effectively separate the GO sheets and slow down the stacking by self-intercalation effect. And introduced Ag into Pd lattice effectively modify the electronic structure of Pd and form OH− at a lower potential, which is helpful the oxidation of CO and weakens the poisoning effect of CO, improving the catalytic performance. After 20,000 s stability test, the residual current density value of mPd1Ag1@FrGO is 659 mA mgPd-1, which is 20 times of Pd/C (JM). After 4 cycles of 20,000 s i-t test, its current density only dropped by 18.2%. In addition, the catalyst mPd1Ag1@FrGO has good regeneration ability. After 6 cycles of regeneration, the residual current density value is 878.1 mA mgPd-1.