Gold nanoparticles supported on carbon nitride: Influence of surface hydroxyls on low temperature carbon monoxide oxidation

This paper reports the synthesis of 2.5 nm gold clusters on the oxygen free and chemically labile support carbon nitride (C ₃N ₄). Despite having small particle sizes and high enough water partial pressure these Au/C ₃N ₄ catalysts are inactive for the gas phase and liquid phase oxidation of carbon monoxide. The reason for the lack of activity is attributed to the lack of surface -OH groups on the C ₃N ₄. These OH groups are argued to be responsible for the activation of CO in the oxidation of CO. The importance of basic -OH groups explains the well documented dependence of support isoelectric point versus catalytic activity.