fig2

Figure 2. (A) XANES spectra for the Co foil, CoO and CoSA+NC/NPSC; (B) FT-EXAFS spectra of Co K-edge in CoSA+NC/NPSC; (C) k2-weighted WT-EXAFS signals of Co foil, CoS2 and CoSA+NC/NPSC; EXAFS analysis of CoSA+NC/NPSC at (D) k and (E) R spaces, respectively; Fitting results of Co K-edge FT-EXAFS analysis in (F) k and (G) R spaces for CoSA+NC/NPSC. XANES: X-ray absorption near edge structure; EXAFS: extended X-ray absorption fine structure; FT-EXAFS: fourier transform- extended X-ray absorption fine structure; WT-EXAFS: wavelet transform- extended X-ray absorption fine structure.