Cu and Cu-Fe Bi-Metal Nanoparticles Encapsulated in Hollow S-1 Zeolite for Reverse Water Gas Shift Reaction

Abstract

The hollow hierarchical structure Cu@S and CuFe0.5@S catalysts were successfully synthesized through the “dissolution-recrystallization” (D-R) method for the reverse water gas shift reaction (RWGS). The encapsulated catalysts had a hierarchical porous structure and better dispersion of Cu particles than the Cu-S and CuFe0.5-S samples prepared via the conventional impregnation method. Furthermore, CuFe0.5-S and CuFe0.5@S catalysts showed higher CO2 conversion and 100% selectivity of CO at the entire temperature range investigated in this work compared to the monometallic catalysts Cu-S and Cu@S. Interestingly, the reaction activity of all the samples increased according to the sequence: CuFe0.5@S > CuFe0.5-S > Cu@S > Cu-S at 400–550 °C under atmospheric pressure. These results indicate that the higher dispersion of encapsulation structure and the enhanced surface basicity derived from the addition of Fe play crucial roles in enhancing the catalytic performance of Cu-based catalysts in the RWGS reaction.