Fig. 3

Spectroscopic characterizations of the Pt/S–C catalysts. a Fourier transform of k2-weighted Pt L3-edge of PtSA/S–C, PtNC/S–C, PtO2, PtS2, and Pt foil. b Wavelet transform for the k2-weighted EXAFS spectra of PtSA/S–C, PtNC/S–C, PtO2, PtS2, and Pt foil. c High-resolution XPS spectra (Pt 4f) of PtSA/S–C, PtNC/S–C, and PtS2. d High-resolution XPS spectra (Pt 4f) of PtNC/BP2000-300 and PtNC/S–C-500. e Normalized XANES spectra at the Pt L3-edge of PtNC/BP2000-300 and PtNC/S–C-500