Isomorphous substitution method to fabricating pure phase Al‐doped zinc malachite: defects driven promotion improvement and enhanced synergy between Cu−ZnO

Abstract A two‐step strategy for making Al‐doped pure‐phase zinc malachite has been demonstrated to improve the microstructure properties of Cu/ZnO/Al 2 O 3 catalyst. The optimal incorporation of Al into the single‐phase zinc malachite lattice improved promotional effect of Al to utmost extent. Introduction of Al in zinc malachite lattice leads to a dispersion and stabilization of CuO domains and perceive maximum degree of intimate solid solution of the three metal oxides in the calcined catalysts owing to the enhanced “dilution” effect. The maximum of 8 mol% of Al based on Cu could be introduced in zinc malachite without any by‐phase formation. The best performing catalyst, IS32‐Al 0.08 C unveil ∼8.8‐fold increase in the methanol formation rate as compared to the unpromoted catalyst. Al was found to promote the synergy between Cu−ZnO by introducing defect sites as well as electronically modifying ZnO reducibility. For the first time, such an effective strategy of promoter incorporation is reported for the formation of Cu/ZnO/Al 2 O 3 catalyst with exceptional microstructure properties.