Fig. 2. (a) Raman spectra of the original PCNS carbonization; (b) FT-IR spectra of PCNS and their derivatives; (c) TGA diagrams of PCNS and their derivatives; (d) total XPS spectra of PCNS and their derivatives. (e) PCNS, (f) PCNS@CMCS@8-HQ represent high-resolution XPS spectra of C 1s.