“…[24][25][26] The Si 2p XPS spectra in Figure 3B can be matched with three peaks with the value of 100.08, 101.46, and 102.18 eV, corresponding to SiC, SiCO, and SiCO x , respectively. [20][21][22] The C 1s XPS spectra in Figure 3C give rise to peaks at 282.48, 284.83, 286.46, and 288.68 eV, corresponding to NbC, SiC, C-C, C-O, and C O, respectively. 22,27 The O 1s XPS spectra in Figure 3D can be fitted into two peaks with value of 530.02, 530.66, 531.83, and 533.42 eV, attributed to NbO, NbO 2 , SiCO/SiCO x , and absorbed oxygen, respectively.…”