Promoted effect of PANI as electron transfer promoter on CO oxidation over Au/TiO2

Abstract

Since a high electron density of Au surfaces can be conducive to the oxidation of CO over the supported Au nanoparticles, the conductive polymer polyaniline (PANI) was assembled into Au/TiO2 to prepare a Au/TiO2–PANI catalyst for oxidizing CO. It is found that PANI could be well wedged with Au/TiO2, which remarkably promoted the oxidation of CO over the TiO2 supported Au nanoparticles at room temperature. Moreover, the presence of a trace amount of H2O could promote the oxidation of CO over the Au/TiO2–PANI catalyst. Based on the testing results of structure characteristic, electrochemical impedance and adsorbing CO of Au/TiO2–PANI, it was proposed that the PANI could be acted as an electron transmitter to promote the electron transfer from TiO2 to Au, resulting in the increase of surface electron density of Au sites and then the promoted activation of CO adsorbed at Au sites.