Fig. 3. (a) Rh 3d XPS spectra of Rh-Co₃O₄ BNSs and pure Rh; (b) Co 2p XPS spectra of Rh-Co₃O₄ BNSs and Co₃O₄ BNSs; (c) the normalized Co K-edge XANES spectra; (d) Fourier-transforms of K³-weight Co K-edge EXAFS spectra; (e) the normalized Rh K-edge XANES spectra; (f) Fourier-transforms of the K³-weight Rh K-edge EXAFS spectra; (g) wavelet transforms for the K³-weight Co K-edge EXAFS signals; (h) wavelet transforms for the K³-weight Rh K-edge EXAFS signals.