“…The deconvoluted Si 2p spectra reveal the existence of peaks at a binding energy of 102.32, 103.00, and 103.51 eV due to the presence of Si-C, SiO 2 , and Si-O, respectively (Figure 6E). [42,43] Apart from the silicate peaks, the XPS spectra of cobalt was deconvoluted into four peaks at binding energy, 781.08, 782.89, 786.88, and 797.43 eV, indicating the existence of different states of cobalt on MCM-41. Furthermore, the formation of clear spin-orbit doublets located at around 781.08 and 782.89 eV was due to the contribution of Co 3+ associated to Co 2p 3/2 oxidation states (Figure 6F), respectively.…”