Fig. 3: Atomic structural and chemical states analyses of Fe/Cu dual atom catalyst.
From: Fe/Cu diatomic catalysts for electrochemical nitrate reduction to ammonia
a High-resolution N 1s XPS spectrum of Fe/Cu-HNG. b Raman spectra of rGO, HNG, and Fe/Cu-HNG. c Cu K-edge XANES spectra of Fe/Cu-HNG, Cu/Cu-HNG, Cu-HNG, Cu foil, CuO, and Cu2O. d Fe K-edge XANES spectra of Fe/Cu-HNG, Fe/Fe-HNG, Fe-HNG, Fe foil, FeO, and Fe2O3. e k3-weighted FT of χ(k)-function from the Cu K-edge EXAFS. f k3-weighted FT of χ(k)-function from the Cu K-edge EXAFS. WT images of the Cu K-edge from g Cu-HNG h Fe/Cu-HNG, and the Fe K-edge from i Fe-HNG, and j Fe/Cu-HNG. k Proposed schematic model of Fe/Cu-HNG: Fe (aqua), Cu (orange), N (blue), and C (brown). l Fitting results of the EXAFS spectra of Fe/Cu-HNG at k-space and R space of Fe K-edge.
