Synergy effects between Sn and SiO2 on enhancing the anti-poison ability to CO for ethanol electrooxidation

Pd1-Snx/SiO2 nanocatalysts with high CO anti-poisoning ability towards ethanol oxidation reaction (EOR) have been prepared by chemical reduction method. These Pd1-Snx/SiO2 nanocatalysts are used as an anode catalyst for EOR, and achieve a factor of 3.5 enhancement in residual current density (567 mA mgPd−1) for EOR over commercial Pd1-Sn0.5/C (163 mA mgPd−1) after a 20000 s durability test. The density functional theory (DFT) calculations are carried out to study the function of introducing Sn and SiO2 into Pd-based nanocatalysts, the results reveal that the introduction of oxophilic metals Sn and SiO2 support into catalysts could reduce the adsorption energy of OHads on Pd1-Snx/SiO2 nanocatalysts, which would facilitate the oxidation of the CO adsorbed on Pd surface. These catalysts are in favor of excellent electrocatalytic performance and high CO anti-poisoning ability towards EOR.