fig2

Figure 2. (A) FTIR spectra and (B) Raman spectra of LVP@NC-x (x = 0.5, 0.8, 1) composites. (C) Nitrogen adsorption-desorption isotherms of [email protected] composite, the inset is the corresponding plot of pore size distribution. (D) XPS survey spectra and high-resolution XPS spectra of (E) V 2p, (F) P 2p, (G) O 1s, (H) C 1s, and (I) N 1s of [email protected] composite.