Preparation of sintering-resistant Pt nanocatalysts by dopamine mediation for water-gas shift reaction

A novel strategy for the synthesis of sintering-resistant Pt/Ce-Ti-T catalyst with high activity and stability for water-gas shift (WGS) reaction is demonstrated. By adding dopamine followed by thermal treatment under an inert atmosphere, the Pt/Ce-Ti-T catalyst was obtained after the removal of sacrificial dopamine through oxidation. For a Pt/Ce-Ti catalyst subjected to ageing but without the participation of dopamine, it showed a sharp decrease of CO conversion from ca. 90% to 48% at 400 degrees C within 12 h, while the similarly aged Pt/Ce-Ti-T catalyst displays a CO conversion of ca. 82% and no obvious sign of deactivation. It was found that in the case of Pt/Ce-Ti, there was increase of Pt nanoparticle size from 7.25 to 20.72 nm, while there was no significant increase in the Pt/Ce-Ti-T case (from 7.80 to 8.55 nm). The observation can be associated with the strengthening of metal-support contact as a result of dopamine mediation. The outcome is enhanced interfacial bonding between Pt nanoparticles and the Ce-Ti support, making the Pt/Ce-Ti-T catalyst highly resistant to sintering and has commendable durability for WGS reaction.