Highly Dispersed Antisintering Cu Catalyst from Cu-Al Spinel Oxide Obtained by Using Surface Solid Reaction for Reverse Water-Gas Shift

Inhibiting the sintering of Cu-based catalysts for CO2 reverse water-gas shift (RWGS) reaction is still a great challenge. Herein, Cu-Al spinel supported on Al2O3 was prepared by a surface solid reaction and used as a precursor to obtain Cu particles with high dispersions and high stabilities. Due to the high dispersions of Cu cations in Cu-Al spinel, strong chemical interactions between Cu particles and newly generated Al2O3, and the isolation effects of Al2O3 particles, Cu particles derived from Cu-Al spinel exhibited smaller sizes after H2 reduction, excellent activities, and 300 h stabilities for RWGS reactions. However, Cu particles obtained from the supported CuO precursor showed much larger particle sizes (>70 nm) and inferior activities and stabilities for CO2 reverse water-gas shift reaction. This study made a successful attempt to enhance the activities and stabilities of Cu-based catalysts through changing the oxide precursor.