a) High magnification aberration‐corrected HAADF‐STEM image of atomic Fe/N‐doped graphene catalyst. b) Potential‐dependent FECO in ECR on Fe/N‐doped graphene single‐atom catalysts prepared at different annealing temperatures. c) Free energy diagram for ECR to CO on Fe‐N4 moieties supported on graphene sheets. Reproduced with permission.[
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] Copyright 2018, Wiley‐VCH. d) AC‐HAADF‐STEM images of Co‐N5/HNPCSs catalyst at different magnifications. e) The comparisons of FECO values of Co‐N5/HNPCSs and CoPc catalysts at various constant potentials. f) Calculated free energies of CO2RR on Co‐N5/HNPCSs and other metal phthalocyanines (FePc, CoPc, NiPc, and CuPc). Reproduced with permission.[
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] Copyright 2018, American Chemical Society. g) FECO values of NiPc‐OMe MDE, NiPc MDE, NiPc‐CN MDE, and P‐NiNC at different applied potentials. h) Calculated free energy diagrams of NiPc‐CN‐H2, NiPc‐H2, and NiPc‐OMe‐H2 for CO2RR at −0.11 V versus RHE. Reproduced with permission.[
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] Copyright 2020, Springer Nature Limited.