Ru ions enhancing the interface bonding between the Pt nanoparticle catalyst and perovskite support for super anti-sintering performance

Abstract

Supported noble metal catalysts are widely applied in energy and environmental catalytic reactions; however, noble metal particles are prone to sintering under reaction conditions. Herein, we demonstrate that the introduction of Ru ions in the LaNiO₃ perovskite support produces strong interface bonding between the Pt nanoparticle catalyst and LaNiO₃ support, resulting in super anti-sintering performance of the Pt nanoparticle catalyst. A novel method is developed to synthesize the supported noble metal catalysts by doping Pt and Ru ions into the lattice of LaNiO₃ and then reduction in a hydrogen atmosphere. The different formation energies of both metal ions in the LaNiO₃ lattice induce selective reduction of Pt ions to generate Pt nanoparticles, while Ru ions remained in the LaNiO₃ support. Using CO oxidation as a probe reaction, we find that supported Pt nanoparticles on Ru doped LaNiO₃ hardly change after undergoing a high temperature of 600 °C for 250 h, and the average particle size only increases from 2.1 to 2.4 nm; moreover, the high catalytic activity is maintained. In contrast, without Ru ions, the Pt particles grow from 2.9 to 10.9 nm, and the activity decreases significantly. Experimental and theoretical evidence indicates that Ru ions not only form stable Pt–O–Ru ionic bonds but also enhance the Pt–O bonding on LaNiO₃.