2.

Revealing surface chemical bonding states by XPS. Survey spectra including the electronic core levels (Si 2p, C 1s, N 1s, Cl 2p, and O 1s) and the Auger bands, C 1s and O 1s spectra, and their corresponding Gaussian deconvolution of (a,e,i) Ref, (b,f,j) 1D, (c,g,k) 2D, and (d,h,l) 3D CDC materials, respectively. (m) Representative schemes of the graphitic-N, pyrrolic-N, and pyridinic-N functionalities. N 1s spectra of the N-CDC materials: (n) 1D, (o) 2D, and (p) 3D. Normalized relative concentrations of the characteristic nitrogen functionalities of the N 1s spectra: (q) pyridinic-N, (r) pyrrolic-N, and (s) graphitic-N.