New Theoretical Insights into the Origin of Highly-Effective Dispersion of Cu-Based Catalysts As-Synthesized Using Mg/Zn Doped Malachite as Precursors

摘要

abstract_textpThe effect of Mg substitution into malachite and Zn doped malachite structure has been precisely modeled and theoretically investigated for energetic, geometrical and electronic properties based on density functional theory. The calculations were carried out by well-tested code Cambridge Serial Total Energy Package while the Local Density Approximation was applied to describe the exchange-correlation potential. The Mg substitution added to the structural stability owing to its smallest formation energy and the stability of -Cu-O-Mg- bond provides well dispersed Cu species. In addition, Mg offers higher tendency to form more stable structure with Cu than Zn at high substitution ratio of Mg/Cu. The introduction of Mg further increases the net charges of Zn atoms and reduces the covalent characteristic of Zn-O bond. The densities of states supported the strengthening of covalent characteristic of Zn-O and Cu-O while Mg-O exhibited ionic characteristic with increasing Mg/Zn. Our calculations provide fundamental understanding of Cu/Mg/Zn system resulting in effective Cu dispersion and thermodynamically stable activity./p/abstract_text