A general strategy for preparing pyrrolic-N4 type single-atom catalysts via pre-located isolated atoms

Single-atom catalysts (SACs) have been applied in many fields due to their superior catalytic performance. Because of the unique properties of the single-atom-site, using the single atoms as catalysts to synthesize SACs is promising. In this work, we have successfully achieved Co-1 SAC using Pt-1 atoms as catalysts. More importantly, this synthesis strategy can be extended to achieve Fe and Ni SACs as well. X-ray absorption spectroscopy (XAS) results demonstrate that the achieved Fe, Co, and Ni SACs are in a M-1-pyrrolic N-4 (M= Fe, Co, and Ni) structure. Density functional theory (DFT) studies show that the Co(Cp)(2) dissociation is enhanced by Pt-1 atoms, thus leading to the formation of Co-1 atoms instead of nanoparticles. These SACs are also evaluated under hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), and the nature of active sites under HER are unveiled by the operando XAS studies. These new findings extend the application fields of SACs to catalytic fabrication methodology, which is promising for the rational design of advanced SACs. Synthesizing single-atom catalysts through a general method presents a great challenge. Here the authors report that Fe, Co and Ni single-atom catalysts can be obtained using pre-located isolated Pt atoms as the catalyst and identify the role of Pt single atoms in the synthesis process.

Automated summary

Single-atom catalysts (SACs) have been successfully synthesized using Pt atoms as catalysts to achieve Fe, Co, and Ni SACs. The role of Pt single atoms in the synthesis process was identified and the nature of active sites under hydrogen evolution reaction (HER) was revealed through operando XAS studies. This research extends the application fields of SACs to catalytic fabrication, promising for rational design of advanced SACs.