Fig. 5: Proposed mechanism of NiSA/PCFM.

a Free energy diagram of CO2 to adsorbed *COOH intermediate on N-C and Ni-N4-C doped graphene structure; b Comparisons of Tafel plots. c Graphic illustration of a GDE device; Schematic for d NiSA/PCFM membrane directly used as GDE and e typical GDE cell with catalyst powder loaded onto a gas-diffusion layer via polymer binder.