Tracking Structure and Active Site Evolution in K- and Zn-promoted Nickel Catalysts during CO2 Hydrogenation to Higher Alcohols

Higher alcohols (HA) are valuable industrial chemicals and producing them from CO2 offers a sustainable route. In this context, Ni–Zn–K has shown exceptional activity for CO2-to-HA conversion, with K and Zn promoters steering the selectivity of Ni-based catalysts from mainly CH4 and CO to far more HA, indicating the addition of C-C coupling function. However, the exact nature and structural evolution of active site(s) remain unclear, hindering rational catalyst design. To address this, we have prepared Ni, Ni-Zn, and Ni-Zn-K catalysts on carbon to uncover the role of each component in the activity. Using operando XAS-XRD, we will monitor crystalline phase evolution and changes in the local coordination of Ni and Zn during reaction conditions to reveal structural and electronic factors affecting HA synthesis. The insights gained will not only clarify the nature and dynamics of active sites, but also establish guiding principles to optimize CO2-to-HA catalysts.