Effect of nitrogen co-doping with ruthenium on the catalytic performance of Ba/Ru–N-MC catalysts for ammonia synthesis

Abstract

Nitrogen co-doping with ruthenium mesoporous carbons (Ru–N-MC) was prepared by co-impregnation of sucrose and urea on a RuCl₃/SiO₂ template followed by a thermal carbonization process. The turnover frequency (TOF) of the Ba/Ru–N-MC catalyst in ammonia synthesis is 0.16 s⁻¹ under reaction conditions of 400 °C, pressure of 10 MPa and space velocity of 10 000 h⁻¹. The superior catalytic performance of the Ba/Ru–N-MC is proposed to originate from the strong metal-support interaction between Ru nanoparticles (NPs) and carbon support. In addition to the activity, the Ba/Ru–N-MC catalyst exhibits a long-term stability for 35 h without significant deactivation.