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.