Mechanistic study on the roles of heteroatoms in Ni-based dual-atom catalysts for electrochemical CO2 reduction

The intrinsic catalytic activity of single-atom catalysts (SACs) can be enhanced by incorporating other elements. However, understanding the roles of these heteroatoms is crucial for maximizing catalytic efficiency. In this study, we focused on the electrochemical CO 2 reduction reaction (CO 2 RR) over Ni-based dual-atom catalysts (DACs) containing Zn or Mn using in situ Raman spectroscopy and ab initio molecular dynamics simulations. The NiZn DAC achieved a CO faradaic efficiency of > 99.8% up to a current density of − 300 mA cm −2 . Compared with the Ni SAC and NiMn DAC, the NiZn DAC more effectively facilitated electron transfer by tuning the electronic structure of the catalytically active Ni center, stabilizing the chemisorbed CO 2 intermediates, and accelerating proton transfer by biasing the electron density of the chemisorbed CO 2 intermediates. This study provides insights into the roles of heteroatoms in catalytic activity and will aid the development of highly efficient catalysts.