Gallium-Promoted Strong Metal–Support Interaction over a Supported Cu/ZnO Catalyst for Methanol Steam Reforming

The strong metal–support interaction (SMSI), which involves the encapsulation of the metal nanoparticles with support material to form an overlayer, affects the interfacial structure and electronic characteristics of the supported metal, profoundly influencing its catalytic properties. However, developing facile approaches capable of a achieving controllable, permeable, and stable overlayer, particularly under mild conditions, remains a challenge. Here, we report that the formation process of ZnOx overlayer on Cu can be accelerated by the addition of promoter, aiming at strengthening the SMSI effect. It is found that the introduction of Ga promotes the migration of ZnOx species onto the surface of metallic Cu0 nanoparticles after hydrogen reduction at 300 °C and atmospheric pressure. Such a reconstruction forms more abundant Cu–ZnOx interfacial sites and increases the intrinsic activity by 4.6-fold, as compared to the Cu/ZnO with negligible SMSI, toward the methanol steam reforming reaction. This investigation provides a facile approach for the rational design and optimization of supported metal catalysts and deepens the understanding of the concept of SMSI.