Gas induced surface reconstruction of CuZnSi catalyst for methanol synthesis

Abstract

Reconstruction of heterogeneous catalyst is essential for understanding the structure-performance relationship, however, it still remains limitations of the methodology development. Herein we reveal a gas induced activation strategy to reconstruct the surface of CuZnOx/mSi catalyst through pretreating it in various environments, including CO, H2, and H2&CO mixture. Specifically, high resolution scanning transmission electron microscopy as well as elemental distribution analysis disclosed that H2 pretreatment successfully induced the formation of active Cu nanoparticles which uniformly dispersed on amorphous ZnO layer, whereas CO pretreatment led to the reconstruction of Cu nanoparticles/cluster, resulting in the formation of CuCx nanofibers under the high temperature reaction environment. The catalytic activity of the H2-treated CuZnOx/mSi-H2 is about three times higher than that of the CO-treated CuZnOx/mSi-CO for methanol synthesis. This gas atmosphere induced catalyst reconstruction strategy might pave the way for the rational catalyst design with precise active phase.