fig9
From: Heterogeneous single-atom catalysts for energy process: recent progress, applications and challenges
Figure 9. (A) Illustration of the synthesis of Fe SACs via a MOF-based mixed-ligand strategy. Reproduced from Ref.[114] with permission from Wiley-ACH. (B) Illustration of the host-guest cooperative protection strategy for the fabrication of NiSA-Nx-C catalysts for electrocatalytic CO2 reduction. Reproduced from Ref.[115] with permission from Wiley-ACH.